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Sample records for bacterial-infection screen reveals

  1. Rheumatoid arthritis and bacterial infections

    Directory of Open Access Journals (Sweden)

    N L Prokopjeva

    2008-01-01

    Full Text Available To study features of bacterial infections course in pts with rheumatoid arthritis (RA and changes of laboratory measures after focus of infection sanation. Material and methods. 46 pts with definite rheumatoid arthritis were examined at the time of comorbid infection (Cl detection and after infection focus sanation. Bacteriological test with evaluation of flora sensitivity to antibiotics by disco-diffusion method was performed at baseline and after the course of antibacterial therapy to assess its efficacy. Hemogram, serum fibrinogen, rheumatoid factor, circulating immune complexes (CIC, C-reactive protein levels were assessed. Serum interleukin (IL 1(3, IL6 and neopterin concentrations were examined by immune-enzyme assay in a part of pts. Typical clinical features of Cl were present in only 28 (60,9% pts. 13 (28,3% pts had fever, 12 (26,0% — leukocytosis, 15 (32,6% — changes of leucocyte populations. Some laboratory measures (thrombocytes, fibrinogen, CIC, neopterin levels significantly decreased (p<0,05 after infection focus sanation without correction of disease modifying therapy. Cl quite often develop as asymptomatic processes most often in pts with high activity and can induce disturbances promoting appearance of endothelial dysfunction, atherothrombosis and reduction of life duration. So timely detection and proper sanation of infection focuses should be performed in pts with RA

  2. Differences of serum procalcitonin levels between bacterial infection and flare in systemic lupus erythematosus patients

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    Patrick, J.; Marpaung, B.; Ginting, Y.

    2018-03-01

    Differentiate bacterial infections from flare in SLE patients is difficult to do because clinical symptoms of infection is similar to flare. SLE patients with infection require antibiotic therapy with decreased doses of immunosuppressant while in flare diseases require increased immunosuppressant. Procalcitonin (PCT), a biological marker, increased in serum patients with bacterial infections and expected to be a solution of problem. The aim of this study was to examine the function of PCT serum as marker to differentiate bacterial infection and flare in SLE patients. This cross-sectional study was conducted in Adam Malik Hospital from January-July 2017. We examined 80 patients SLE flare (MEX-SLEDAI>5), screen PCT and culture according to focal infection. Data were statistically analyzed. 80 SLE patients divided into 2 groups: bacterial infection group (31 patients) and non-infection/flare group (49 patients). Median PCT levels of bacterial infection group was 1.66 (0.04-8.45)ng/ml while flare group was 0.12 (0.02-0.81)ng/ml. There was significant difference of serum Procalcitonin level between bacterial infection and flare group in SLE patients (p=0.001). Procalcitonin serum levels can be used as a biomarker to differentiate bacterial infections and flare in SLE patients.

  3. Liver abscess caused by periodontal bacterial infection with Fusobacterium necrophorum.

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    Yoneda, Masato; Kato, Shingo; Mawatari, Hironori; Kirikoshi, Hiroyuki; Imajo, Kento; Fujita, Koji; Endo, Hiroki; Takahashi, Hirokazu; Inamori, Masahiko; Kobayashi, Noritoshi; Kubota, Kensuke; Saito, Satoru; Tohnai, Iwai; Watanuki, Kei; Wada, Koichiro; Maeda, Shin; Nakajima, Atsushi

    2011-02-01

    Liver abscess is recognized as a life-threatening disease. However, even in recent years, approximately 50% of liver abscess cases are considered to be cryptogenic. Here, we report a case of liver abscess associated with periodontal bacterial infection by Fusobacterium necrophorum, which is commonly found in the oropharyngeal flora. A 36-year-old man presented with fever and contrast-enhanced abdominal computed tomography revealed multiple liver abscesses. F.necrophorum was isolated from oral smears, liver aspirates and blood samples. Liver abscesses caused by periodontal bacterial infection are rare, however, the incidence is expected to increase in the future, as periodontitis is extremely common and is on the rise as one of the most common chronic infections in the world. A systemic survey including periodontitis may be required for the exact diagnosis of the source of infection. © 2011 The Japan Society of Hepatology.

  4. Associations between bacterial infections and blood pressure in pregnancy.

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    Petry, Clive J; Ong, Ken K; Hughes, Ieuan A; Acerini, Carlo L; Dunger, David B

    2017-10-01

    To test the hypothesis that bacterial infections in pregnancy are related to maternal blood pressure. Bacterial infection was assessed using antibiotic usage as a surrogate and its association with blood pressure in pregnancy tested in the Cambridge Baby Growth Study. Antibiotic usage in pregnancy was self-reported in questionnaires. Blood pressure measurements at four time points in pregnancy were collected from the hospital notes of 622 women. Using all the available blood pressure readings (adjusted for weeks gestation) antibiotic usage was associated with a higher mean arterial blood pressure across pregnancy: antibiotics used 85(84, 87)mmHg vs. no antibiotics used 83 (83, 84) mmHg (β=2.3 (0.6, 4.0) mmHg, p=9.6×10 -3 , from 621 individuals). Further analysis revealed that antibiotic usage was associated with diastolic (β=2.3 (0.6, 4.0) mmHg; p=7.0×10 -3 ) more than systolic blood pressure (β=1.4(-0.9, 3.7)mmHg; p=0.2). The effect size associated with antibiotic usage appeared to rise slightly after the first trimester. Bacterial infection in pregnancy, as assessed by self-reported antibiotic usage, is associated with small rises in blood pressure. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  5. Fibrinous pericarditis secondary to bacterial infection in a cat.

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    Tagawa, Michihito; Kurashima, Chihiro; Shimbo, Genya; Omura, Hiroshi; Koyama, Kenji; Horiuchi, Noriyuki; Kobayashi, Yoshiyasu; Kawamoto, Keiko; Miyahara, Kazuro

    2017-06-10

    A three-year-old spayed domestic short-haired cat presented for evaluation of weight loss, cardiomegaly and pleural effusion. Echocardiographic examination demonstrated a thickened pericardium with mild pericardial effusion and a large volume of pleural effusion characterized by exudate. Although the cat was treated with antibiotics, the clinical symptoms did not improve. The cat developed dyspnea and died on day 7. Necropsy revealed a large amount of modified transudates ascites, pleural effusion and markedly dilated pericardium. Histopathological examination revealed severe exudation of fibrin and granulation tissue in a thick layer of the epicardium. The cat was diagnosed with fibrinous pericarditis secondary to bacterial infection.

  6. Association of RNA Biosignatures With Bacterial Infections in Febrile Infants Aged 60 Days or Younger

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    Mahajan, Prashant; Kuppermann, Nathan; Mejias, Asuncion; Suarez, Nicolas; Chaussabel, Damien; Casper, T. Charles; Smith, Bennett; Alpern, Elizabeth R.; Anders, Jennifer; Atabaki, Shireen M.; Bennett, Jonathan E.; Blumberg, Stephen; Bonsu, Bema; Borgialli, Dominic; Brayer, Anne; Browne, Lorin; Cohen, Daniel M.; Crain, Ellen F.; Cruz, Andrea T.; Dayan, Peter S.; Gattu, Rajender; Greenberg, Richard; Hoyle, John D.; Jaffe, David M.; Levine, Deborah A.; Lillis, Kathleen; Linakis, James G.; Muenzer, Jared; Nigrovic, Lise E.; Powell, Elizabeth C.; Rogers, Alexander J.; Roosevelt, Genie; Ruddy, Richard M.; Saunders, Mary; Tunik, Michael G.; Tzimenatos, Leah; Vitale, Melissa; Dean, J. Michael; Ramilo, Octavio

    2016-01-01

    IMPORTANCE Young febrile infants are at substantial risk of serious bacterial infections; however, the current culture-based diagnosis has limitations. Analysis of host expression patterns (“RNA biosignatures”) in response to infections may provide an alternative diagnostic approach. OBJECTIVE To assess whether RNA biosignatures can distinguish febrile infants aged 60 days or younger with and without serious bacterial infections. DESIGN, SETTING, AND PARTICIPANTS Prospective observational study involving a convenience sample of febrile infants 60 days or younger evaluated for fever (temperature >38° C) in 22 emergency departments from December 2008 to December 2010 who underwent laboratory evaluations including blood cultures. A random sample of infants with and without bacterial infections was selected for RNA biosignature analysis. Afebrile healthy infants served as controls. Blood samples were collected for cultures and RNA biosignatures. Bioinformatics tools were applied to define RNA biosignatures to classify febrile infants by infection type. EXPOSURE RNA biosignatures compared with cultures for discriminating febrile infants with and without bacterial infections and infants with bacteremia from those without bacterial infections. MAIN OUTCOMES AND MEASURES Bacterial infection confirmed by culture. Performance of RNA biosignatures was compared with routine laboratory screening tests and Yale Observation Scale (YOS) scores. RESULTS Of 1883 febrile infants (median age, 37 days; 55.7%boys), RNA biosignatures were measured in 279 randomly selected infants (89 with bacterial infections—including 32 with bacteremia and 15 with urinary tract infections—and 190 without bacterial infections), and 19 afebrile healthy infants. Sixty-six classifier genes were identified that distinguished infants with and without bacterial infections in the test set with 87%(95%CI, 73%-95%) sensitivity and 89% (95%CI, 81%-93%) specificity. Ten classifier genes distinguished

  7. Sustainable strategies for treatment of bacterial infections

    DEFF Research Database (Denmark)

    Molin, Søren

    2014-01-01

    Resistance to antibiotics and the consequential failures of treatment based on antibiotics makes microbial infections a major threat to human health. This problem combined with rapidly increasing life-style disease problems challenge our healtcare system as well as the pharma industry, and if we do...... not in a foreseeable future develop novel approaches and strategies to combat bacterial infections, many people will be at risk of dying from even trivial infections for which we until recently had highly effective antibiotics. We have for a number of years investigated chronic bacterial lung infections in patients...... suffering from cystic fibrosis. These infections are optimal model scenarios for studies of antibiotic resistance development and microbial adaptation, and we suggest that this information should be useful when designing new anti-microbial strategies. In this respect it will be important to choose...

  8. Preventing Bacterial Infections using Metal Oxides Nanocoatings on Bone Implant

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    Duceac, L. D.; Straticiuc, S.; Hanganu, E.; Stafie, L.; Calin, G.; Gavrilescu, S. L.

    2017-06-01

    Nowadays bone implant removal is caused by infection that occurs around it possibly acquired after surgery or during hospitalization. The purpose of this study was to reveal some metal oxides applied as coatings on bone implant thus limiting the usual antibiotics-resistant bacteria colonization. Therefore ZnO, TiO2 and CuO were synthesized and structurally and morphologically analized in order to use them as an alternative antimicrobial agents deposited on bone implant. XRD, SEM, and FTIR characterization techniques were used to identify structure and texture of these nanoscaled metal oxides. These metal oxides nanocoatings on implant surface play a big role in preventing bacterial infection and reducing surgical complications.

  9. Bacterial infections of pulp and periodontal origin.

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    González-Moles, Miguel Angel; González, Nabila M

    2004-01-01

    The anatomical and structural characteristics of the pulp make this structure prone to altering as a result of, for instance, periodontal conditions (proximity), iatrogenic alterations, infections and involvement of vascular and nerve structures (it is surrounded by hard tissues that prevent expansion), to name just a few. Pulpitis is a process that courses with pain of varying intensity that allows us to determine the location of the lesion in clinical terms. Its evolution varies and may even progress to pulpar necrosis that in turn, produces neuritis-like pain. Diagnosis is established by means of clinical symptomatology and supported by X-rays, palpation of tissues at painful sites, application of electrical stimuli, heat, etc. Periodontitis is a bacterial infection originating in the apex. The most important form is the so-called acute apical periodontitis that arises as a result of a prior episode of pulpitis. It is characterized by acute pain located in the tooth, accompanied by the feeling of having a long-tooth. The patient refers being unable to chew on that side; there may be painful mobility of the tooth and an outflow of pus that alleviates symptoms. X-rays do not provide a lot of information, but may attest to a widening of the apical space. This pathology may disseminate to surrounding tissues, leading to conditions of considerable severity.

  10. Utility of the serum C-reactive protein for detection of occult bacterial infection in children.

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    Isaacman, Daniel J; Burke, Bonnie L

    2002-09-01

    To assess the utility of serum C-reactive protein (CRP) as a screen for occult bacterial infection in children. Febrile children ages 3 to 36 months who visited an urban children's hospital emergency department and received a complete blood cell count and blood culture as part of their evaluation were prospectively enrolled from February 2, 2000, through May 30, 2001. Informed consent was obtained for the withdrawal of an additional 1-mL aliquot of blood for use in CRP evaluation. Logistic regression and receiver operator characteristic (ROC) curves were modeled for each predictor to identify optimal test values, and were compared using likelihood ratio tests. Two hundred fifty-six patients were included in the analysis, with a median age of 15.3 months (range, 3.1-35.2 months) and median temperature at triage 40.0 degrees C (range, 39.0 degrees C-41.3 degrees C). Twenty-nine (11.3%) cases of occult bacterial infection (OBI) were identified, including 17 cases of pneumonia, 9 cases of urinary tract infection, and 3 cases of bacteremia. The median white blood cell count in this data set was 12.9 x 10(3)/ micro L [corrected] (range, 3.6-39.1 x10(3)/ micro L) [corrected], the median absolute neutrophil count (ANC) was 7.12 x 10(3)/L [corrected] (range, 0.56-28.16 x10(3)/L) [corrected], and the median CRP level was 1.7 mg/dL (range, 0.2-43.3 mg/dL). The optimal cut-off point for CRP in this data set (4.4 mg/dL) achieved a sensitivity of 63% and a specificity of 81% for detection of OBI in this population. Comparing models using cut-off values from individual laboratory predictors (ANC, white blood cell count, and CRP) that maximized sensitivity and specificity revealed that a model using an ANC of 10.6 x10(3)/L [corrected] (sensitivity, 69%; specificity, 79%) was the best predictive model. Adding CRP to the model insignificantly increased sensitivity to 79%, while significantly decreasing specificity to 50%. Active monitoring of emergency department blood cultures

  11. Role of the chronic bacterial infection in urinary bladder carcinogenesis

    International Nuclear Information System (INIS)

    Higgy, N.A.

    1985-01-01

    The purpose of this thesis was to determine whether or not bacterial infection of the urinary bladder had a role in urinary bladder carcinogenesis. To investigate this proposition, four separate studies were conducted. The first study developed an experimental animal model where bacterial infection of the urinary bladder could be introduced and maintained for a period in excess of one year. The method of infection, inoculation of bacteria (Escherichia coli type 04) subserosally into the vesical wall, successfully caused persistent infection in the majority of animals. In the second study the temporal effects of bacterial infection on the induction of urothelial ornithine decarboxylase (ODC) and 3 H-thymidine uptake and DNA synthesis were examined. Bacterial infection of the urinary bladder induced urothelial ODC with a peak in enzyme activity 6 hr after infection. 3 H-Thymidine uptake and DNA synthesis peaked 48 hr after infection and coincided with the urothelial hyperplasia that occurred in response to the infection. In the third study the specific bladder carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was given to rats concurrent with the urinary bacterial infection. In the fourth study rats were administered sodium nitrate and either dibutylamine or piperazine in the drinking water. The infected group developed bladder tumors while none were detected in the non-infected rats. From these studies it may be concluded that bacterial infection may have a significant role in the process of urinary bladder carcinogenesis

  12. BACTERIAL INFECTIONS IN HEMATOPOIETIC STEM CELL TRANSPLANT RECIPIENTS

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    Elisa Balletto

    2015-07-01

    Full Text Available Bacterial infections are major complications after Hematopoietic Stem Cell Transplant (HSCT. They consist mainly of bloodstream infections (BSI, followed by pneumonia and gastrointestinal infections, including typhlitis and Clostridium difficile infection. Microbiological data come mostly from BSI. Coagulase negative staphylococci and Enterobacteriaceae are the most frequent pathogens causing approximately 25% of BSI each, followed by enterococci, P. aeruginosa and viridans streptococci. Bacterial pneumonia is frequent after HSCT, and Gram-negatives are predominant. Clostridium difficile infection affects approximately 15% of HSCT recipients, being more frequent in case of allogeneic than autologous HSCT. The epidemiology and the prevalence of resistant strains vary significantly between transplant centres. In some regions, multi-drug resistant Gram-negative rods are increasingly frequent. In others, vancomycin-resistant enterococci are predominant. In the era of an increasing resistance to antibiotics, the efficacy of fluoroquinolone prophylaxis and standard treatment of febrile neutropenia have been questioned. Therefore, thorough evaluation of local epidemiology is mandatory in order to decide the need for prophylaxis and the choice of the best regimen for empirical treatment of febrile neutropenia. For the latter, individualised approach has been proposed, consisting of either escalation or de-escalation strategy. De-escalation strategy is recommended is resistant bacteria should be covered upfront, mainly in patients with severe clinical presentation and previous infection or colonisation with a resistant pathogens. Non-pharmacological interventions, such as screening for resistant bacteria, applying isolation and contact precautions should be put in place in order to limit the spread of MDR bacteria. Antimicrobial stewardship program should be implemented in transplant centres.

  13. Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.

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    Pukkila-Worley, Read; Feinbaum, Rhonda; Kirienko, Natalia V; Larkins-Ford, Jonah; Conery, Annie L; Ausubel, Frederick M

    2012-01-01

    The nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. Here we show that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we show that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (∼1.3% of all genes) in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data show that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens.

  14. Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.

    Directory of Open Access Journals (Sweden)

    Read Pukkila-Worley

    Full Text Available The nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. Here we show that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we show that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (∼1.3% of all genes in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data show that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens.

  15. DMPD: Role of Nods in bacterial infection. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17379560 Role of Nods in bacterial infection. Bourhis LL, Werts C. Microbes Infect.... 2007 Apr;9(5):629-36. Epub 2007 Jan 27. (.png) (.svg) (.html) (.csml) Show Role of Nods in bacterial infect...ion. PubmedID 17379560 Title Role of Nods in bacterial infection. Authors Bourhis LL, Werts C. Publication M

  16. Severe bacterial infections in patients with non-transfusion-dependent thalassemia: prevalence and clinical risk factors

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    Nattiya Teawtrakul

    2015-10-01

    Conclusion: The prevalence of bacterial infection in patients with NTDT was found to be moderate. Time after splenectomy >10 years, deferoxamine therapy, and iron overload may be clinical risk factors for severe bacterial infection in patients with NTDT. Bacterial infection should be recognized in splenectomized patients with NTDT, particularly those who have an iron overload.

  17. TBK1 protects vacuolar integrity during intracellular bacterial infection.

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    Andrea L Radtke

    2007-03-01

    Full Text Available TANK-binding kinase-1 (TBK1 is an integral component of Type I interferon induction by microbial infection. The importance of TBK1 and Type I interferon in antiviral immunity is well established, but the function of TBK1 in bacterial infection is unclear. Upon infection of murine embryonic fibroblasts with Salmonella enterica serovar Typhimurium (Salmonella, more extensive bacterial proliferation was observed in tbk1(-/- than tbk1(+/+ cells. TBK1 kinase activity was required for restriction of bacterial infection, but interferon regulatory factor-3 or Type I interferon did not contribute to this TBK1-dependent function. In tbk1(-/-cells, Salmonella, enteropathogenic Escherichia coli, and Streptococcus pyogenes escaped from vacuoles into the cytosol where increased replication occurred, which suggests that TBK1 regulates the integrity of pathogen-containing vacuoles. Knockdown of tbk1 in macrophages and epithelial cells also resulted in increased bacterial localization in the cytosol, indicating that the role of TBK1 in maintaining vacuolar integrity is relevant in different cell types. Taken together, these data demonstrate a requirement for TBK1 in control of bacterial infection distinct from its established role in antiviral immunity.

  18. TBK1 Protects Vacuolar Integrity during Intracellular Bacterial Infection

    Science.gov (United States)

    Radtke, Andrea L; Delbridge, Laura M; Balachandran, Siddharth; Barber, Glen N; O'Riordan, Mary X. D

    2007-01-01

    TANK-binding kinase-1 (TBK1) is an integral component of Type I interferon induction by microbial infection. The importance of TBK1 and Type I interferon in antiviral immunity is well established, but the function of TBK1 in bacterial infection is unclear. Upon infection of murine embryonic fibroblasts with Salmonella enterica serovar Typhimurium (Salmonella), more extensive bacterial proliferation was observed in tbk1−/− than tbk1+/+ cells. TBK1 kinase activity was required for restriction of bacterial infection, but interferon regulatory factor-3 or Type I interferon did not contribute to this TBK1-dependent function. In tbk1−/−cells, Salmonella, enteropathogenic Escherichia coli, and Streptococcus pyogenes escaped from vacuoles into the cytosol where increased replication occurred, which suggests that TBK1 regulates the integrity of pathogen-containing vacuoles. Knockdown of tbk1 in macrophages and epithelial cells also resulted in increased bacterial localization in the cytosol, indicating that the role of TBK1 in maintaining vacuolar integrity is relevant in different cell types. Taken together, these data demonstrate a requirement for TBK1 in control of bacterial infection distinct from its established role in antiviral immunity. PMID:17335348

  19. Technetium-99m labelled antimicrobial peptides discriminate between bacterial infections and sterile inflammations

    International Nuclear Information System (INIS)

    Welling, M.M.; Pauwels, E.K.J.; Paulusma-Annema, A.; Nibbering, P.H.; Balter, H.S.

    2000-01-01

    99m Tc-labelled UBI peptides revealed that these peptides were rapidly removed from the circulation by renal excretion. Similar data were observed for 99m Tc-labelled defensin 1-3. Our data for 99m Tc-labelled hLF and related peptides indicate that these compounds are less favourable for infection detection. Taken together, 99m Tc-labelled UBI 18-35 and UBI 29-41 enable discrimination between bacterial infections and sterile inflammatory processes in both mice and rabbits. Based on their characteristics, we consider these peptides the candidates of preference for detection of bacterial infections in man. (orig.)

  20. Bacterial infections in horses: a retrospective study at the University Equine Clinic of Bern.

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    Panchaud, Y; Gerber, V; Rossano, A; Perreten, V

    2010-04-01

    Bacterial infections present a major challenge in equine medicine. Therapy should be based on bacteriological diagnosis to successfully minimize the increasing number of infections caused by multidrug-resistant bacteria. The present study is a retrospective analysis of bacteriological results from purulent infections in horses admitted at the University Equine Clinic of Bern from 2004 to 2008. From 378 samples analyzed, 557 isolates were identified, of which Staphylococcus aureus, Streptococcus equi subsp. zooepidemicus and coliforms were the most common. Special attention was paid to infections with methicillin-resistant S. aureus (MRSA) ST398 and a non-MRSA, multidrug-resistant S. aureus clone ST1 (BERN100). Screening of newly-admitted horses showed that 2.2 % were carriers of MRSA. Consequent hygiene measures taken at the Clinic helped to overcome a MRSA outbreak and decrease the number of MRSA infections.

  1. Radiosynthesis and preclinical studies of 177Lu-labeled sulfadiazine. A possible theranostic agent for deep-seated bacterial infection

    International Nuclear Information System (INIS)

    Syed Ali Raza Naqvi; Rashid Rasheed; Muhammad Tauqeer Ahmed; Ameer Fawad Zahoor

    2017-01-01

    Sulfadiazine acts through inhibition of bacterial dihydropteroate synthetase. The radio-labeling of sulfadiazine with lutetium-177 ( 177 Lu) is expected to serve as a theranostic agent for deep-seated bacterial infections. The radiosynthesis of 177 Lu-sulfadiazine indicated a > 95% yield under optimized reaction conditions, and promising stability was found in blood serum. Biodistribution data in the absence of infection revealed minimal accumulation in key body organs. Kidneys were the main excretory organs, showed an uptake of 1.76 ± 0.09% ID/g organ at 6-h post-injection. Biodistribution, scintigraphic data, glomerular filtration rate, and cytotoxicity results encourage clinical investigation of 177 Lu-sulfadiazine as a novel theranostic agent for deep-seated bacterial infection. (author)

  2. [Clinical efficacy of flomoxef in neonatal bacterial infection].

    Science.gov (United States)

    Sakata, H; Hirano, Y; Maruyama, S

    1993-03-01

    One hundred and seventy one neonates were treated with flomoxef (FMOX) and the clinical efficacy and safety were evaluated. The ages of the patients ranged from 0 to 28 days, and their body weights from 450 to 4300 g. Dose levels were 12.4 to 24.9 mg/kg every 8 or 12 hours for 1 to 10 days. Fifty two patients who responded to the FMOX treatment included 5 neonates with sepsis, 17 with suspected sepsis, 9 with urinary tract infections, 12 with pneumonia, 8 with intrauterine infections, and 1 with omphalitis. The other neonates could not be retrospectively diagnosed as bacterial infections. Of 52 patients, clinical results were excellent in 15, good in 34, fair in 1, and poor in 2. And the FMOX treatment was effective in 13 out of 14 patients in which causative bacteria were identified. The drug was well tolerated, but 6 neonates out of 33 over 5 days old had diarrhea. From these results, empiric treatment with FMOX against neonatal bacterial infection was as clinically useful as that of combination with ampicillin and gentamicin or cefotaxime and ampicillin in our neonatal intensive care unit. But, as this study did not include neonate with meningitis, efficacy to meningitis was not evaluated.

  3. Nanosized Selenium: A Novel Platform Technology to Prevent Bacterial Infections

    Science.gov (United States)

    Wang, Qi

    As an important category of bacterial infections, healthcare-associated infections (HAIs) are considered an increasing threat to the safety and health of patients worldwide. HAIs lead to extended hospital stays, contribute to increased medical costs, and are a significant cause of morbidity and mortality. In the United States, infections encountered in the hospital or a health care facility affect more than 1.7 million patients, cost 35.7 billion to 45 billion, and contribute to 88,000 deaths in hospitals annually. The most conventional and widely accepted method to fight against bacterial infections is using antibiotics. However, because of the widespread and sometimes inappropriate use of antibiotics, many strains of bacteria have rapidly developed antibiotic resistance. Those new, stronger bacteria pose serious, worldwide threats to public health and welfare. In 2014, the World Health Organization (WHO) reported antibiotic resistance as a global serious threat that is no longer a prediction for the future but is now reality. It has the potential to affect anyone, of any age, in any country. The most effective strategy to prevent antibiotic resistance is minimizing the use of antibiotics. In recent years, nanomaterials have been investigated as one of the potential substitutes of antibiotics. As a result of their vastly increased ratio of surface area to volume, nanomaterials will likely exert a stronger interaction with bacteria which may affect bacterial growth and propagation. A major concern of most existing antibacterial nanomaterials, like silver nanoparticles, is their potential toxicity. But selenium is a non-metallic material and a required nutrition for the human body, which is recommended by the FDA at a 53 to 60 μg daily intake. Nanosized selenium is considered to be healthier and less toxic compared with many metal-based nanomaterials due to the generation of reactive oxygen species from metals, especially heavy metals. Therefore, the objectives of

  4. Incidence and Predictors of Bacterial infection in Febrile Children with Sickle Cell Disease.

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    Morrissey, Benita J; Bycroft, Thomas P; Almossawi, Ofran; Wilkey, Olufunke B; Daniels, Justin G

    2015-01-01

    Children with sickle cell disease are at increased risk of developing bacteremia and other serious bacterial infections. Fever is a common symptom in sickle cell disease and can also occur with sickle cell crises and viral infections. We aimed to evaluate the incidence and predictors of bacteremia and bacterial infection in children with sickle cell disease presenting with fever to a district hospital and sickle cell center in London. A retrospective analysis was performed on all attendances of children (aged under 16 years) with sickle cell disease presenting with a fever of 38.5 °C or higher over a 1-year period. Confirmed bacterial infection was defined as bacteremia, bacterial meningitis, urinary tract infection (UTI), pneumonia, osteomyelitis or other bacterial infection with positive identification of organism. Children were defined as having a suspected bacterial infection if a bacterial infection was suspected clinically, but no organism was identified. Over a 1-year period there were 88 episodes analyzed in 59 children. Bacteremia occurred in 3.4% of episodes and confirmed bacterial infection in 7.0%. Suspected bacterial infection occurred in 33.0%. One death occurred from Salmonella typhirium septicemia. C-reactive protein (CRP) level and white blood cell (WBC) count were both significantly associated with bacterial infection (p = 0.004 and 0.02, respectively.) In conclusion, bacterial infections continue to be a significant problem in children with sickle cell disease. C-reactive protein was significantly associated with bacterial infections, and could be included in clinical risk criteria for febrile children with sickle cell disease.

  5. Antimicrobial Nanoparticle for the Treatment of Bacterial Infection

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    Pornpattananangkul, Dissaya

    Liposomes are spherical lipid vesicles with bilayered membrane structure, which have been recognized as one of the most widely used carriers for delivering a myriad of pharmaceuticals. Liposomes can carry both hydrophilic and hydrophobic agents with high efficiency and protect them from undesired effects of external conditions. However, the applications of liposomes are usually limited by their instability during storage. They are inclined to fuse with one another immediately after preparation, resulting in undesired mixing, increase in size, and payload loss. To overcome this limitation, this dissertation will focus on the technology to stabilize liposomes during storage and destabilize at specific conditions in order to allow controllable therapeutic release, as well as demonstrate their application to treat one of the bacterial infection diseases, acne vulgaris. The first area of this research is stimuli-responsive liposomes development, where the liposomes are stabilized by introducing gold nanoparticles to adsorb to their surface. As a result, the liposomes are prevented from fusing with one another and undesirable payload release during storage or physiological environments. Moreover, therapeutic is controllably released depending on environment conditions, such as acidic pH and bacterial virulence factor. In case of acid-responsive liposomes, the bound gold nanoparticles can effectively prevent liposomes from fusing with one another at neutral pH value, while at acidic environment (e.g. pHhuman skin are typically acidic. Demonstrated by fluorescent and antimicrobial experiments, the bound gold nanoparticles effectively prevent LipoLA from fusing with one another at neutral pH value. However, at acidic condition, the gold particles detatch from LipoLA surface, allowing the fusion with P.acnes membrane and lauric acid delivery, resulting in a complete killing effect. The stimuli-responsive liposomes presented here provide a new, safe, and effective approach to

  6. Bacterial infection in deep paraspinal muscles in a parturient following epidural analgesia.

    Science.gov (United States)

    Yang, Ying-Wei; Chen, Wei-Ting; Chen, Jui-Yuan; Lee, She-Chin; Chang, Yi; Wen, Yeong-Ray

    2011-06-01

    We report a case of paraspinal muscle infection shortly after epidural analgesia for labor pain in a nulliparous parturient who was subjected to emergent Cesarean section because of fetal distress. Epidural morphine was administered for 3 days for postoperative pain control. She began to have constant lower back pain on postpartum Day 4. Magnetic resonance image study revealed a broad area of subcutaneous edema with a continuum along the catheter trajectory deep to the paraspinal muscles. An injection-related bacterial infection was suspected; the patient was treated with intravenous antibiotics and was soon cured uncomplicatedly. Epidural analgesia is effective to control labor pain and, in general, it is safe. However, the sequelae of complicated infection may be underestimated. We herein report a case complicated by iatrogenic infection, discuss the causes, and give suggestions for prevention. Copyright © 2011. Published by Elsevier B.V.

  7. Platelet concentrates: reducing the risk of transfusion-transmitted bacterial infections

    Directory of Open Access Journals (Sweden)

    de Korte D

    2014-06-01

    Full Text Available Dirk de Korte,1 Jan H Marcelis2 1Department of Product and Process Development, Sanquin Blood Bank, Amsterdam, 2Department of Microbiology, St Elisabeth Hospital, Tilburg, the Netherlands Abstract: The introduction of a combination of interventions during collection of whole-blood or platelet concentrates has been successful in lowering the degree of bacterial contamination in the final product, the platelet concentrate, by 50%–75%. These interventions were improved donor questionnaires, best-practice skin disinfection, and diversion of first blood volume. These interventions have reduced the number of bacteria present in the platelet concentrates. In combination with screening for bacterial contamination of platelet concentrates with a culture method, the degree of transfusion-transmitted bacterial infection has been reduced significantly. Due to the very low initial bacteria counts upon collection of the products, the need for improved sensitivity of early screenings tests or highly selective point-of-issue tests remains. The latter should be rapid and easy to perform. An alternative approach might be the implementation of pathogen-inactivation methods for cellular blood products to reduce the amount of pathogens. However, these methods are costly, and so far not proved to be cost-effective, especially in countries with an already-low incidence of transfusion-transmitted infections by viruses, parasites, or bacteria. Keywords: blood products, bacterial contamination, screening, point of issue, pathogen inactivation

  8. A Novel 3D Skin Explant Model to Study Anaerobic Bacterial Infection

    Directory of Open Access Journals (Sweden)

    Grazieli Maboni

    2017-09-01

    Full Text Available Skin infection studies are often limited by financial and ethical constraints, and alternatives, such as monolayer cell culture, do not reflect many cellular processes limiting their application. For a more functional replacement, 3D skin culture models offer many advantages such as the maintenance of the tissue structure and the cell types present in the host environment. A 3D skin culture model can be set up using tissues acquired from surgical procedures or post slaughter, making it a cost effective and attractive alternative to animal experimentation. The majority of 3D culture models have been established for aerobic pathogens, but currently there are no models for anaerobic skin infections. Footrot is an anaerobic bacterial infection which affects the ovine interdigital skin causing a substantial animal welfare and financial impact worldwide. Dichelobacter nodosus is a Gram-negative anaerobic bacterium and the causative agent of footrot. The mechanism of infection and host immune response to D. nodosus is poorly understood. Here we present a novel 3D skin ex vivo model to study anaerobic bacterial infections using ovine skin explants infected with D. nodosus. Our results demonstrate that D. nodosus can invade the skin explant, and that altered expression of key inflammatory markers could be quantified in the culture media. The viability of explants was assessed by tissue integrity (histopathological features and cell death (DNA fragmentation over 76 h showing the model was stable for 28 h. D. nodosus was quantified in all infected skin explants by qPCR and the bacterium was visualized invading the epidermis by Fluorescent in situ Hybridization. Measurement of pro-inflammatory cytokines/chemokines in the culture media revealed that the explants released IL1β in response to bacteria. In contrast, levels of CXCL8 production were no different to mock-infected explants. The 3D skin model realistically simulates the interdigital skin and has

  9. THE ROLE OF PROCALCITONIN IN BACTERIAL INFECTION RECOGNITION

    Directory of Open Access Journals (Sweden)

    Lucija Gabršek

    2001-12-01

    Full Text Available Background. Early recognition of bacterial infection and antibiotic treatment are very important in critically ill patients. Procalcitonin (PCT is a marker of bacterial infections accompanied by systemic inflammatory response. Higher values were also noticed with parasitical and fungal infections, but PCT is normal in viral and systemic diseases. The aim of this study was to assess whether PCT is better marker for bacterial infections than C-reactive protein (CRP and if they have a prognostic value.Methods. 34 patients were included into our retrospective study. All of them had clinical or laboratory signs of infection at the first PCT determination. We measured PCT, CRP, erythrocyte sedimentation rate (SR and leukocyte count. On the base of microbiological results we divided patients into three groups. Group A had patients with sterile cultures, group B included the ones with negative blood cultures, but from other cultures causative agents were identified. The patients in group C had positive blood cultures. Retrospectively we studied PCT and CRP values among groups and among survivors and non survivors.Results. An average median value of PCT in group A was 8.9 ± 13.3 ng/ml, in group B 5.3 ± 9.3 ng/ml and in group C 21.0 ± 25.0 ng/ml. In group B, the average median value of PCT was significantly higher than in group C (p = 0.019, but that was not the case in group A (p = 0.23. The average median values of CRP were 129.9 ± 67.4 mg/l in group A, 104.3 ± 60.1 mg/l in group B and 117.4 ± 46.1 mg/l in group C. Between groups, differences of CRP values were not statistically significant. The average initial value of PCT in group of non survivors (8.9 ± 49 was not significantly higher then in group of survivors (3.14 ± 55.4 (p = 0.48. The average final value was significantly higher (p = 0.0013 in group of non survivors (13.1 ± 23.9 ng/l than in group of survivors (0.55 ± 7.3 ng/ml. In both groups the average initial values of CRP did not

  10. Technetium-99m labelled antimicrobial peptides discriminate between bacterial infections and sterile inflammations

    Energy Technology Data Exchange (ETDEWEB)

    Welling, M.M.; Pauwels, E.K.J. [Dept. of Radiology, Leiden University Medical Center (LUMC) (Netherlands); Paulusma-Annema, A.; Nibbering, P.H. [Dept. of Infectious Diseases, Leiden University Medical Center (Netherlands); Balter, H.S. [Centro Investigaciones Nucleares, Univ. of the Republic Uruguay, Montevideo (Uruguay)

    2000-03-01

    into the biodistribution of {sup 99m}Tc-labelled UBI peptides revealed that these peptides were rapidly removed from the circulation by renal excretion. Similar data were observed for {sup 99m}Tc-labelled defensin 1-3. Our data for {sup 99m}Tc-labelled hLF and related peptides indicate that these compounds are less favourable for infection detection. Taken together, {sup 99m}Tc-labelled UBI 18-35 and UBI 29-41 enable discrimination between bacterial infections and sterile inflammatory processes in both mice and rabbits. Based on their characteristics, we consider these peptides the candidates of preference for detection of bacterial infections in man. (orig.)

  11. Contribution of Bacterial Infection to Male Infertility in Nigerians

    Directory of Open Access Journals (Sweden)

    Emokpae MA

    2009-05-01

    Full Text Available There is disagreement as to the influence of certain microbial infection on male infertility and such agents are ignored. The incidence of these microbial agents in seminal fluid isolates is on the increase. This study therefore evaluates the prevalence of male factor infertility and contribution of microbial infection to male infertility in Kano, northern Nigeria. Seminal fluid analysis in five hundred males who were investigated for infertility was evaluated using the 5th generation SQ AII C-P sperm quality analyzer and the Neubaeur counting chamber. The result indicates that 58.2% had sperm density less than twenty million per millilitre. The oligospermic subjects (sperm density 2-19 millions/ml were 27.6%, severe oligospermic (sperm density less than 2 million 13.2% and azoospermia, 17.4%. Asthenospermia (motility less than 50% decrease from 44.8% in oligospermia to 24.0% in severe oligospermia. Teratospermia (abnormal morphology greater than 50% also deteriorated from 46.3% to 35.4% in oligospermic and severe oligospermic males respectively. Seminal fluid infection increases with decreasing sperm density, motility and morphology. The prevalence of abnormal sperm indices and bacterial infection is high and Staphylococcus aureus infection should be treated and no longer ignored in the management of male factor infertility.

  12. Combating multidrug-resistant Gram-negative bacterial infections.

    Science.gov (United States)

    Xu, Ze-Qi; Flavin, Michael T; Flavin, John

    2014-02-01

    Multidrug-resistant (MDR) bacterial infections, especially those caused by Gram-negative pathogens, have emerged as one of the world's greatest health threats. The development of novel antibiotics to treat MDR Gram-negative bacteria has, however, stagnated over the last half century. This review provides an overview of recent R&D activities in the search for novel antibiotics against MDR Gram-negatives. It provides emphasis in three key areas. First, the article looks at new analogs of existing antibiotic molecules such as β-lactams, tetracyclines, and aminoglycoside as well as agents against novel bacterial targets such as aminoacyl-tRNA synthetase and peptide deformylase. Second, it also examines alternative strategies to conventional approaches including cationic antimicrobial peptides, siderophores, efflux pump inhibitors, therapeutic antibodies, and renewed interest in abandoned treatments or those with limited indications. Third, the authors aim to provide an update on the current clinical development status for each drug candidate. The traditional analog approach is insufficient to meet the formidable challenge brought forth by MDR superbugs. With the disappointing results of the genomics approach for delivering novel targets and drug candidates, alternative strategies to permeate the bacterial cell membrane, enhance influx, disrupt efflux, and target specific pathogens via therapeutic antibodies are attractive and promising. Coupled with incentivized business models, governmental policies, and a clarified regulatory pathway, it is hoped that the antibiotic pipeline will be filled with an effective armamentarium to safeguard global health.

  13. DMPD: The role of Toll-like receptors and Nod proteins in bacterial infection. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15476921 The role of Toll-like receptors and Nod proteins in bacterial infection. P...of Toll-like receptors and Nod proteins in bacterial infection. PubmedID 15476921 Title The role of Toll-like receptors and Nod prote...ins in bacterial infection. Authors Philpott DJ, Girardi

  14. "Bacterial infections in visceral leishmaniasis in Children’s Medical Center 1966-2000 "

    Directory of Open Access Journals (Sweden)

    "Tabatabaei P "

    2002-07-01

    Full Text Available Background: Bacterial infections are seen in patients with visceral leishmaniasis. This study was conducted to determine the incidence of such infections and the more common infections agents. Materials and Methods: During the 15-years period in a prospective study from 1986 to 2000, 123 patients with visceral leishmaniasis were studied in the Children Medical Center. Results: From all the cases, 41 (33 percent patients had Also bacterial infections. Respiratory tract, urinary system, Middle ear were the most common sites of infection. Conclusion: When bacterial Infection is suspected in these patients, empiric antibiotic therapy should be started immediately after appropriate diagnostic procedures are taken.

  15. Evaluation of localized bacterial infection using radioisotope-labeled nucleosides imaging modality

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Su Jin; Kang, Joo Hyun; Lee, Yong Jin; Lee, Tae Sup; Kim, Kwang Il; Lee, Kyo Chul; An, Gwang II; Cheon, Gi Jeong; Lim, Sang Moo [KIRAMS, Seoul (Korea, Republic of); Lim, Sang Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    Conventional diagnostic methods for infections are difficult to distinguish localized bacterial infections from sites of sterile inflammation. For this reason, the importance of developing methods to image bacterial infections is widely recognized. In this study to acquire bacterial infection imaging with radiolabeled nucleosides, in vitro bacterial thymidine kinase (tk) activities of Salmonella typhimurium with [{sup 18}F]FLT and [{sup 125}I]IVDU were measured and localized infections model in BALB/c mice was imaged with [{sup 18}F]FLT or [{sup 125}I]FIAU

  16. Circulating Chemokine Levels in Febrile Infants With Serious Bacterial Infections

    Directory of Open Access Journals (Sweden)

    Hsiu-Lin Chen

    2009-12-01

    Full Text Available Early diagnosis of serious bacterial infections (SBI in febrile young infants based on clinical symptoms and signs is difficult. This study aimed to evaluate the diagnostic values of circulating chemokines and C-reactive protein (CRP levels in febrile young infants < 3 months of age with suspected SBI. We enrolled 43 febrile young infants < 3 months of age with clinically suspected SBI who were admitted to the neonatal intensive care unit or complete nursing unit of the pediatric department of Kaohsiung Medical University Hospital between December 2006 and July 2007. Blood was drawn from the patients at admission, and complete blood counts, plasma levels of CRP, granulocyte colony-stimulating factor (G-CSF, and chemokines, including interleukin-8 (IL-8, macrophage inflammatory protein-1α, macrophage inflammatory protein-1β, monokine induced by interferon-γ, and monocyte chemotactic protein-1 were measured. Patients’ symptoms and signs, length of hospital stay, main diagnosis, and results of routine blood tests and microbiological culture results were recorded. Twenty-six infants (60.5% were diagnosed with SBI, while 17 (39.5% had no evidence of SBI based on the results of bacterial cultures. CRP, IL-8 and G-CSF levels were significantly higher in the infants with SBI than in those without SBI. Plasma levels of other chemokines were not significantly different between the groups. The area under the receiver-operating characteristic (ROC curve for differentiating between the presence and absence of SBI was 0.79 for CRP level. Diagnostic accuracy was further improved by combining CRP and IL-8, when the area under the ROC curve increased to 0.91. CRP levels were superior to IL-8 and G-CSF levels for predicting SBI in febrile infants at initial survey. IL-8 levels could be used as an additional diagnostic tool in the initial evaluation of febrile young infants, allowing clinicians to treat these patients more appropriately.

  17. Bacterial infections in cynomolgus monkeys given small molecule immunomodulatory antagonists.

    Science.gov (United States)

    Price, Karen D

    2010-01-01

    Opportunistic infections (OIs) during the course of non-clinical toxicity studies can serve as a clinical indicator of immunosuppression. In monkeys, severity may be magnified since the possibility for fecal-oral and cage-to-cage transmission of bacteria exists, reserve capacity is low, and clinical signs of infection are not easily detected until the infectious process is well underway. This review summarizes a case study presented at the HESI-ILSI ITC-Sponsored workshop on Naturally Occurring Infections in Non-human Primates and Immunotoxicity Implications. It gives an overview on the impact of bacterial infections in monkeys on the development and regulatory assessment of three closely-related representative small molecule immunomodulatory (anti-inflammatory) drug candidates all inhibiting the same drug target. The infections, which sometimes progressed to bacteremia and death, originally manifested in the skin, upper respiratory tract, gastrointestinal tract, and less frequently as soft tissue abscesses. Infections were sporadic and not observed in all studies despite coverage of equivalent or higher systemic exposures or longer durations of treatment. To address concerns regarding inconsistency in the presentation and type of findings and their potential relationship to infection, steps were taken to identify causative agents (via culture, microscopy), implement various intervention and treatment regimens (supportive care, antibiotics, drug holiday), demonstrate reversibility of clinical and immune effects, and study major immune components/mechanisms affected (cytokine/stress protein profiling, immune cell phenotyping, and humoral/innate immune cell function tests). Appropriate diagnosis and characterization of the infection was critical to discrimination of these findings as a secondary pharmacologic effect rather than a direct drug-related target organ effect, and also guided clinical protocol design and regulatory acceptance.

  18. Bacterial infections in cirrhosis: Role of proton pump inhibitors and intestinal permeability

    NARCIS (Netherlands)

    L.G. van Vlerken (Lotte); E.J. Huisman (Ellen); B. van Hoek (Bart); W. Renooij (W.); F.W.M. de Rooij (Felix); P.D. Siersema (Peter); K.J. van Erpecum (Karel)

    2012-01-01

    textabstractBackground Cirrhotic patients are at considerable risk for bacterial infections, possibly through increased intestinal permeability and bacterial overgrowth. Proton pump inhibitors (PPIs) may increase infection risk. We aimed to explore the potential association between PPI use and

  19. Viral and atypical bacterial infections in the outpatient pediatric cystic fibrosis clinic

    DEFF Research Database (Denmark)

    Olesen, Hanne Vebert; Nielsen, Lars P; Schiotz, Peter Oluf

    2006-01-01

    BACKGROUND: Respiratory viral and atypical bacterial infections are associated with pulmonary exacerbations and hospitalisations in cystic fibrosis patients. We wanted to study the impact of such infections on children attending the outpatient clinic. METHODS: Seventy-five children were followed...

  20. An overview of the role of bacterial infection in male infertility

    Directory of Open Access Journals (Sweden)

    Hamed Fanaei

    2013-03-01

    Full Text Available An important cause of male infertility is the bacterial infections of the genitourinary tract. These infections affect sperm cell function and whole spermatogenesis and also cause deterioration in spermatogenesis, obstruction of the seminal tract, and impairment of spermatozoa function. The most important bacteria associated with genitourinary tract infections include chlamydia trachomatis, Neisseria gonorrhoeae, and genital mycoplasma species. Inappropriate or delayed therapy of the bacterial infections of the genitourinary tract will lead to reduced fertility and, subsequently in severe cases, infertility. In other words, a good understanding of the interaction between bacterial infections and the reproductive system plays an important role in the treatment of infertile men. In this review article, we will discuss clinical and laboratory findings related to the bacterial infection of the genitourinary tract and its effects on male infertility.

  1. Procalcitonin and albumin as prognostic biomarkers in elderly patients with a risk of bacterial infection.

    Science.gov (United States)

    Higashikawa, Toshihiro; Okuro, Masashi; Ishigami, Keiichirou; Mae, Kunihiro; Sangen, Ryusho; Mizuno, Takurou; Usuda, Daisuke; Saito, Atushi; Kasamaki, Yuji; Fukuda, Akihiro; Saito, Hitoshi; Morimoto, Shigeto; Kanda, Tsugiyasu

    2018-01-01

    Aim This study was performed to investigate serum procalcitonin (PCT) and albumin (Alb) as prognostic biomarkers in elderly patients at risk of bacterial infection. Methods Serum PCT was measured in 270 hospitalized patients (mean age, 77.4 years) with suspected bacterial infection. The PCT-negative (2.5 g/dL), no significant difference in survival was observed between the PCT-positive and -negative groups. However, within the Alb-negative group (≤2.5 g/dL), the survival rate was significantly lower in the PCT-positive than -negative group. PCT was strongly associated with CRP and Alb, and having both PCT positivity and Alb negativity was a prognostic factor for elderly people at risk of bacterial infection. Conclusions Combined measurement of PCT with Alb is expected to be a valuable tool to assess prognosis in elderly people at risk of bacterial infection.

  2. Correlation between the neutrophil-lymphocyte count ratio and bacterial infection in patient with human immunodeficiency virus

    Science.gov (United States)

    Kusnadi, D.; Liwang, M. N. I.; Katu, S.; Mubin, A. H.; Halim, R.

    2018-03-01

    Parameters for starting antibiotic therapy such as CRP andleukocytosis are considered non-specific. Previous studies have shown the Neutrophil-Lymphocyte Count Ratio (NLCR) can serve as the basis of bacterial infection, the level of infection, and the basis of antibiotic therapy. Compared with the Procalcitonin parameter, this NLCR is rapid, an inexpensive and requires no additional sampling. To determine the correlation between The Neutrophil-LymphocyteCount Ratio to bacterial infection in HIV patients. This study was a cross-sectional observational approach to HIV subject at Wahidin Sudirohusodo and Hasanuddin University Hospital. The subjects performed routine blood, microbiology test,and blood Procalcitonin levels tests. Then performed NLCR calculations based on routine blood results. The subjects then grouped the presence or absence of bacterial infection.In 146 study subjects, there were 78 (53.4%) with bacterial infections and 68 (46.6%) without bacterial infection as controls. Subjects with bacterial infections had higher total neutrophils (84.83) compared with non-bacterial infections. Subjects with bacterial infections had total lymphocytes with an average of 8.51 lower than non-bacterial infections. Subjects with bacterial infections had higher NLCR values with an average of 12.80. The Neutrophil-Lymphocyte Count Ratio can become a marker of bacterial infection in HIV patients.

  3. Bacterial Infection of Fly Ovaries Reduces Egg Production and Induces Local Hemocyte Activation

    OpenAIRE

    Brandt, Stephanie M.; Schneider, David S.

    2007-01-01

    Morbidity, the state of being diseased, is an important aspect of pathogenesis that has gone relatively unstudied in fruit flies. Our interest is in characterizing how bacterial pathogenesis affects various physiologies of the fly. We chose to examine the fly ovary because we found bacterial infection had a striking effect on fly reproduction. We observed decreased egg laying after bacterial infection that correlated with increased bacterial virulence. We also found that bacteria colonized th...

  4. Predictors of serious bacterial infections in pediatric burn patients with fever.

    Science.gov (United States)

    Vyles, David; Sinha, Madhumita; Rosenberg, David I; Foster, Kevin N; Tran, Melissa; Drachman, David

    2014-01-01

    To determine predictors of serious bacterial infections in pediatric burn patients with fever (core temp ≥38.5°C), the authors conducted a retrospective review of medical records of pediatric (0-18 years) patients admitted to the Arizona Burn Center between 2008 and 2011 with greater than 5% TBSA and inpatient hospitalization for ≥72 hours. The study group comprised patients with a febrile episode during their inpatient stay. Serious bacterial infection (the primary outcome variable) was defined as: bacteremia, urinary tract infection, meningitis (blood, urine, or cerebrospinal fluid culture positive for a pathogen respectively), pneumonia, line, and wound infection. A generalized estimating equation analysis was done to predict the presence or absence of serious bacterial infection. Of 1082 pediatric burn patients hospitalized during the study period, 353 met the study eligibility criteria. A total of 108 patients (30.6%) had at least one fever episode (fever group). No difference in demographic characteristics was noted between the fever and no-fever groups; significant differences were observed for: third-degree TBSA, second-degree TBSA, total operating room visits, length of stay, Injury Severity Score, and death. A total of 47.2% of the patients had one or more episodes of fever with serious bacterial infection. In a generalized estimating equation predictive model, presence of a central line, second-, and third-degree TBSA were predictive of serious bacterial infection in burn patients with fever. In this study, individual clinical variables such as tachypnea and tachycardia were not predictive of serious bacterial infections, but the presence of a central line, and larger TBSA were significant predictors of serious bacterial infections. Younger age (P =.08) and ventilator support (P =.057) also approached significance as predictors of serious bacterial infections.

  5. Bilateral endogenous Candida albicans subretinal abscess with suspected mixed bacterial infection

    Directory of Open Access Journals (Sweden)

    Arai Y

    2014-10-01

    Full Text Available Yusuke Arai,1 Yukihiro Sato,1 Atsushi Yoshida,1 Hidetoshi Kawashima,1 Toshikatsu Kaburaki,2 Harumi Gomi3 1Department of Ophthalmology, Jichi Medical University, Tochigi, Japan; 2Department of Ophthalmology, The University of Tokyo, Graduate School of Medicine, Tokyo, Japan; 3Center for Clinical Infectious Diseases, Jichi Medical University, Tochigi, Japan Purpose: Candida albicans subretinal abscess is extremely rare. To our knowledge, only one unilateral case has been reported. Herein, we report one bilateral case. Mixed bacterial infection was also suspected based on broad-range real-time polymerase chain reaction.Methods: A 64-year-old man being treated with oral corticosteroids for interstitial pneumonia visited us for visual loss in the left eye. Best corrected visual acuity (BCVA was 20/20 in the right eye and 8/200 in the left eye. Funduscopy revealed round yellowish-white subretinal lesions with retinal hemorrhage in both eyes.Results: Broad-range polymerase chain reaction of the vitreous fluid from the left eye showed a high copy count of bacterial 16s ribosome RNA. Despite large doses of antibiotics, the abscess expanded and vision decreased to light perception in the left eye. Exenteration of the left eye was performed followed by microscopic examination showing Gram-negative bacilli, and C. albicans was also cultured. Antibiotics and the maximum doses of antifungal drugs were administered. However, the abscess in the right eye expanded, and BCVA decreased to 2/200. Vitrectomy and silicone oil tamponade were performed. Vitreous fluid culture revealed C. albicans. At 16 months follow-up, BCVA was stable at 4/200 with healing of the subretinal abscess under silicone oil.Conclusion: Since C. albicans subretinal abscess is extremely rare and there was a concurrent mixed bacterial infection, diagnostic procedures in our bilateral case were more complicated than usual. C. albicans infection should be included in the differential diagnosis

  6. Bacteriophage therapy to combat bacterial infections in poultry.

    Science.gov (United States)

    Wernicki, Andrzej; Nowaczek, Anna; Urban-Chmiel, Renata

    2017-09-16

    Infections in poultry are an economic and health problem in Europe and worldwide. The most common infections are associated with salmonellosis, colibacillosis, campylobacteriosis, and others. The prevalence of Campylobacter-positive poultry flocks in European countries varies from 18% to 90%. In the United States, the prevalence of infected flocks is nearly 90%. A similar percentage of infection has been noted for salmonellosis (about 75-90%) and E. coli (90-95%). The occurence of Clostridium perfringens is a major problem for the poultry industry, with some estimates suggesting colonization of as many as 95% of chickens, resulting in clinical or subclinical infections. In the US, annual economic losses due to Salmonella infections run from $1.188 billion to over $11.588 billion, based on an estimated 1.92 million cases. Similar costs are observed in the case of other types of infections. In 2005 economic losses in the the poultry industry due to mortalities reached 1,000,000 USD.Infections caused by these pathogens, often through poultry products, are also a serious public health issue.The progressive increase in the number of multi-drug resistant bacteria and the complete ban on the use of antibiotics in livestock feed in the EU, as well as the partial ban in the US, have led to the growth of research on the use of bacteriophages to combat bacterial infections in humans and animals.The high success rate and safety of phage therapy in comparison with antibiotics are partly due to their specificity for selected bacteria and the ability to infect only one species, serotype or strain. This mechanism does not cause the destruction of commensal bacterial flora. Phages are currently being used with success in humans and animals in targeted therapies for slow-healing infections. They have also found application in the US in eliminating pathogens from the surface of foods of animal and plant origin. At a time of growing antibiotic resistance in bacteria and the resulting

  7. Alkylation sensitivity screens reveal a conserved cross-species functionome

    Science.gov (United States)

    Svilar, David; Dyavaiah, Madhu; Brown, Ashley R.; Tang, Jiang-bo; Li, Jianfeng; McDonald, Peter R.; Shun, Tong Ying; Braganza, Andrea; Wang, Xiao-hong; Maniar, Salony; St Croix, Claudette M.; Lazo, John S.; Pollack, Ian F.; Begley, Thomas J.; Sobol, Robert W.

    2013-01-01

    To identify genes that contribute to chemotherapy resistance in glioblastoma, we conducted a synthetic lethal screen in a chemotherapy-resistant glioblastoma derived cell line with the clinical alkylator temozolomide (TMZ) and an siRNA library tailored towards “druggable” targets. Select DNA repair genes in the screen were validated independently, confirming the DNA glycosylases UNG and MYH as well as MPG to be involved in the response to high dose TMZ. The involvement of UNG and MYH is likely the result of a TMZ-induced burst of reactive oxygen species. We then compared the human TMZ sensitizing genes identified in our screen with those previously identified from alkylator screens conducted in E. coli and S. cerevisiae. The conserved biological processes across all three species composes an Alkylation Functionome that includes many novel proteins not previously thought to impact alkylator resistance. This high-throughput screen, validation and cross-species analysis was then followed by a mechanistic analysis of two essential nodes: base excision repair (BER) DNA glycosylases (UNG, human and mag1, S. cerevisiae) and protein modification systems, including UBE3B and ICMT in human cells or pby1, lip22, stp22 and aim22 in S. cerevisiae. The conserved processes of BER and protein modification were dual targeted and yielded additive sensitization to alkylators in S. cerevisiae. In contrast, dual targeting of BER and protein modification genes in human cells did not increase sensitivity, suggesting an epistatic relationship. Importantly, these studies provide potential new targets to overcome alkylating agent resistance. PMID:23038810

  8. A genetic screen reveals Arabidopsis stomatal and/or apoplastic defenses against Pseudomonas syringae pv. tomato DC3000.

    Directory of Open Access Journals (Sweden)

    Weiqing Zeng

    2011-10-01

    Full Text Available Bacterial infection of plants often begins with colonization of the plant surface, followed by entry into the plant through wounds and natural openings (such as stomata, multiplication in the intercellular space (apoplast of the infected tissues, and dissemination of bacteria to other plants. Historically, most studies assess bacterial infection based on final outcomes of disease and/or pathogen growth using whole infected tissues; few studies have genetically distinguished the contribution of different host cell types in response to an infection. The phytotoxin coronatine (COR is produced by several pathovars of Pseudomonas syringae. COR-deficient mutants of P. s. tomato (Pst DC3000 are severely compromised in virulence, especially when inoculated onto the plant surface. We report here a genetic screen to identify Arabidopsis mutants that could rescue the virulence of COR-deficient mutant bacteria. Among the susceptible to coronatine-deficient Pst DC3000 (scord mutants were two that were defective in stomatal closure response, two that were defective in apoplast defense, and four that were defective in both stomatal and apoplast defense. Isolation of these three classes of mutants suggests that stomatal and apoplastic defenses are integrated in plants, but are genetically separable, and that COR is important for Pst DC3000 to overcome both stomatal guard cell- and apoplastic mesophyll cell-based defenses. Of the six mutants defective in bacterium-triggered stomatal closure, three are defective in salicylic acid (SA-induced stomatal closure, but exhibit normal stomatal closure in response to abscisic acid (ABA, and scord7 is compromised in both SA- and ABA-induced stomatal closure. We have cloned SCORD3, which is required for salicylic acid (SA biosynthesis, and SCORD5, which encodes an ATP-binding cassette (ABC protein, AtGCN20/AtABCF3, predicted to be involved in stress-associated protein translation control. Identification of SCORD5 begins to

  9. Hyperspectral image analysis for rapid and accurate discrimination of bacterial infections: A benchmark study.

    Science.gov (United States)

    Arrigoni, Simone; Turra, Giovanni; Signoroni, Alberto

    2017-09-01

    With the rapid diffusion of Full Laboratory Automation systems, Clinical Microbiology is currently experiencing a new digital revolution. The ability to capture and process large amounts of visual data from microbiological specimen processing enables the definition of completely new objectives. These include the direct identification of pathogens growing on culturing plates, with expected improvements in rapid definition of the right treatment for patients affected by bacterial infections. In this framework, the synergies between light spectroscopy and image analysis, offered by hyperspectral imaging, are of prominent interest. This leads us to assess the feasibility of a reliable and rapid discrimination of pathogens through the classification of their spectral signatures extracted from hyperspectral image acquisitions of bacteria colonies growing on blood agar plates. We designed and implemented the whole data acquisition and processing pipeline and performed a comprehensive comparison among 40 combinations of different data preprocessing and classification techniques. High discrimination performance has been achieved also thanks to improved colony segmentation and spectral signature extraction. Experimental results reveal the high accuracy and suitability of the proposed approach, driving the selection of most suitable and scalable classification pipelines and stimulating clinical validations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Natural Product Screening Reveals Naphthoquinone Complex I Bypass Factors.

    Directory of Open Access Journals (Sweden)

    Scott B Vafai

    Full Text Available Deficiency of mitochondrial complex I is encountered in both rare and common diseases, but we have limited therapeutic options to treat this lesion to the oxidative phosphorylation system (OXPHOS. Idebenone and menadione are redox-active molecules capable of rescuing OXPHOS activity by engaging complex I-independent pathways of entry, often referred to as "complex I bypass." In the present study, we created a cellular model of complex I deficiency by using CRISPR genome editing to knock out Ndufa9 in mouse myoblasts, and utilized this cell line to develop a high-throughput screening platform for novel complex I bypass factors. We screened a library of ~40,000 natural product extracts and performed bioassay-guided fractionation on a subset of the top scoring hits. We isolated four plant-derived 1,4-naphthoquinone complex I bypass factors with structural similarity to menadione: chimaphilin and 3-chloro-chimaphilin from Chimaphila umbellata and dehydro-α-lapachone and dehydroiso-α-lapachone from Stereospermum euphoroides. We also tested a small number of structurally related naphthoquinones from commercial sources and identified two additional compounds with complex I bypass activity: 2-methoxy-1,4-naphthoquinone and 2-methoxy-3-methyl-1,4,-naphthoquinone. The six novel complex I bypass factors reported here expand this class of molecules and will be useful as tool compounds for investigating complex I disease biology.

  11. Association between prenatal exposure to bacterial infection and risk of schizophrenia

    DEFF Research Database (Denmark)

    Sørensen, Holger J; Mortensen, Erik Lykke; Reinisch, June M

    2009-01-01

    . Post hoc analyses showed that upper respiratory tract and gonococcal infections were associated with elevated risk of the disease. An association between risk of schizophrenia and prenatal exposure to bacterial infections might be mediated through transplacental passage of maternally produced cytokines......Recent research suggests that prenatal exposure to nonviral infection may be associated with increased risk of schizophrenia, and we hypothesized an association between maternal bacterial infection during pregnancy and elevated offspring risk of schizophrenia. Data on maternal infections from......-34 and 45-47 years, respectively. The effect of prenatal exposure to bacterial infections was adjusted for prenatal exposure to analgesics and parental social status. In a risk set of 7941 individuals, 85 cases (1.1%) of ICD-8 schizophrenia were identified by the age of 32-34 years and 153 cases (1...

  12. Using Natural Products to Treat Resistant and Persistent Bacterial Infections

    Science.gov (United States)

    Deering, Robert W.

    Antimicrobial resistance is a growing threat to human health both worldwide and in the United States. Most concerning is the emergence of multi-drug resistant (MDR) bacterial pathogens, especially the 'ESKAPE' pathogens for which treatment options are dwindling. To complicate the problem, approvals of antibiotic drugs are extremely low and many research and development efforts in the pharmaceutical industry have ceased, leaving little certainty that critical new antibiotics are nearing the clinic. New antibiotics are needed to continue treating these evolving infections. In addition to antibiotics, approaches that aim to inhibit or prevent antimicrobial resistance could be useful. Also, studies that improve our understanding of bacterial pathophysiology could lead to new therapies for infectious disease. Natural products, especially those from the microbial world, have been invaluable as resources for new antibacterial compounds and as insights into bacterial physiology. The goal of this dissertation is to find new ways to treat resistant bacterial infections and learn more about the pathophysiology of these bacteria. Investigations of natural products to find molecules able to be used as new antibiotics or to modulate resistance and other parts of bacterial physiology are crucial aspects of the included studies. The first included study, which is reported in chapter two, details a chemical investigation of a marine Pseudoalteromonas sp. Purification efforts of the microbial metabolites were guided by testing against a resistance nodulation of cell division model of efflux pumps expressed in E. coli. These pumps play an important role in the resistance of MDR Gram negative pathogens such as Pseudomonas aeruginosa and Enterobacteriaceae. Through this process, 3,4-dibromopyrrole-2,5-dione was identified as a potent inhibitor of the RND efflux pumps and showed synergistic effects against the E. coli strain with common antibiotics including fluoroquinolones, beta

  13. Genome-wide miRNA screening reveals miR-310 family members negatively regulate the immune response in Drosophila melanogaster via co-targeting Drosomycin.

    Science.gov (United States)

    Li, Yao; Li, Shengjie; Li, Ruimin; Xu, Jiao; Jin, Ping; Chen, Liming; Ma, Fei

    2017-03-01

    Although innate immunity mediated by Toll signaling has been extensively studied in Drosophila melanogaster, the role of miRNAs in regulating the Toll-mediated immune response remains largely unknown. In this study, following Gram-positive bacterial challenge, we identified 93 differentially expressed miRNAs via genome-wide miRNA screening. These miRNAs were regarded as immune response related (IRR). Eight miRNAs were confirmed to be involved in the Toll-mediated immune response upon Gram-positive bacterial infection through genetic screening of 41 UAS-miRNA lines covering 60 miRNAs of the 93 IRR miRNAs. Interestingly, four out of these eight miRNAs, miR-310, miR-311, miR-312 and miR-313, are clustered miRNAs and belong to the miR-310 family. These miR-310 family members were shown to target and regulate the expression of Drosomycin, an antimicrobial peptide produced by Toll signaling. Taken together, our study implies important regulatory roles of miRNAs in the Toll-mediated innate immune response of Drosophila upon Gram-positive bacterial infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Molecular characteristics of hemoglobins in blood clam and their immune responses to bacterial infection.

    Science.gov (United States)

    Xu, Bin; Zhang, Yanan; Jing, Zhao; Fan, Tingjun

    2017-06-01

    Bivalve hemoglobins have antibacterial activities, while the underlying mechanisms remain poorly understood. In our study, three full-length cDNAs of hemoglobins from blood clam skHbs were obtained, encoding putative polypeptides of 147, 150, and 152 amino acids, respectively. Predicted advanced protein structures showed that the skHbs had amphipathic antibacterial structures, displayed the typical structural characteristics of proteins with globin-like fold containing numerous alpha-helixes, and forming a homodimeric skHbI and a heterotetrameric skHbII complex. After injected with alive and heat-killed Gram-positive bacteria Bacillus subtilis, the mRNA levels of skHbI and skHbII were both significantly upregulated through increasing the expression of peptidoglycan recognition protein-like (PGRP-like) protein and Toll-like receptor (TLR-like) protein induced by peptidoglycan on the surface of the bacteria, but there were no obvious differences in their protein levels. Besides, reactive oxygen species (ROS) was detected to participate in the resistance to B. subtilis. These implied that skHbs could involve in the innate immune responses to Gram-positive bacterial infection directly with their amphipathic structures and indirectly by increasing ROS production through PGRP triggering Toll pathway. In conclusion, our findings reveal the structural characteristics of skHbs and their mechanism against Gram-positive bacteria thereby providing the molecular evidence for fundamental innate antibacterial activities by invoking respiratory proteins. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Surface charge-conversion polymeric nanoparticles for photodynamic treatment of urinary tract bacterial infections

    International Nuclear Information System (INIS)

    Liu, Shijie; Shao, Chen; Qiao, Shenglin; Li, Lili; Qi, Guobin; Lin, Yaoxin; Qiao, Zengying; Wang, Hao

    2015-01-01

    Urinary tract infections are typical bacterial infections which result in a number of economic burdens. With increasing antibiotic resistance, it is urgent that new approaches are explored that can eliminate pathogenic bacteria without inducing drug resistance. Antimicrobial photodynamic therapy (PDT) is a new promising tactic. It is a gentle in situ photochemical reaction in which a photosensitizer (PS) generates reactive oxygen species (ROS) under laser irradiation. In this work, we have demonstrated Chlorin e6 (Ce6) encapsulated charge-conversion polymeric nanoparticles (NPs) for efficiently targeting and killing pathogenic bacteria in a weakly acidic urinary tract infection environment. Owing to the surface charge conversion of NPs in an acidic environment, the NPs exhibited enhanced recognition for Gram-positive (ex. S. aureus) and Gram-negative (ex. E. coli) bacteria due to the charge interaction. Also, those NPs showed significant antibacterial efficacy in vitro with low cytotoxicity. The MIC value of NPs to E. coli is 17.91 μg ml"−"1, compared with the free Ce6 value of 29.85 μg ml"−"1. Finally, a mouse acute cystitis model was used to assess the photodynamic therapy effects in urinary tract infections. A significant decline (P < 0.05) in bacterial cells between NPs and free Ce6 occurred in urine after photodynamic therapy treatment. And the plated counting results revealed a remarkable bacterial cells drop (P < 0.05) in the sacrificed bladder tissue. Above all, this nanotechnology strategy opens a new door for the treatment of urinary tract infections with minimal side effects. (paper)

  16. Long-term impact of systemic bacterial infection on the cerebral vasculature and microglia

    Directory of Open Access Journals (Sweden)

    Püntener Ursula

    2012-06-01

    Full Text Available Abstract Background Systemic infection leads to generation of inflammatory mediators that result in metabolic and behavioural changes. Repeated or chronic systemic inflammation leads to a state of innate immune tolerance: a protective mechanism against overactivity of the immune system. In this study, we investigated the immune adaptation of microglia and brain vascular endothelial cells in response to systemic inflammation or bacterial infection. Methods Mice were given repeated doses of lipopolysaccharide (LPS or a single injection of live Salmonella typhimurium. Inflammatory cytokines were measured in serum, spleen and brain, and microglial phenotype studied by immunohistochemistry. To assess priming of the innate immune response in the brain, mice were infected with Salmonella typhimurium and subsequently challenged with a focal unilateral intracerebral injection of LPS. Results Repeated systemic LPS challenges resulted in increased brain IL-1β, TNF-α and IL-12 levels, despite attenuated systemic cytokine production. Each LPS challenge induced significant changes in burrowing behaviour. In contrast, brain IL-1β and IL-12 levels in Salmonella typhimurium-infected mice increased over three weeks, with high interferon-γ levels in the circulation. Behavioural changes were only observed during the acute phase of the infection. Microglia and cerebral vasculature display an activated phenotype, and focal intracerebral injection of LPS four weeks after infection results in an exaggerated local inflammatory response when compared to non-infected mice. Conclusions These studies reveal that the innate immune cells in the brain do not become tolerant to systemic infection, but are primed instead. This may lead to prolonged and damaging cytokine production that may have a profound effect on the onset and/or progression of pre-existing neurodegenerative disease.

  17. Surface charge-conversion polymeric nanoparticles for photodynamic treatment of urinary tract bacterial infections

    Science.gov (United States)

    Liu, Shijie; Qiao, Shenglin; Li, Lili; Qi, Guobin; Lin, Yaoxin; Qiao, Zengying; Wang, Hao; Shao, Chen

    2015-12-01

    Urinary tract infections are typical bacterial infections which result in a number of economic burdens. With increasing antibiotic resistance, it is urgent that new approaches are explored that can eliminate pathogenic bacteria without inducing drug resistance. Antimicrobial photodynamic therapy (PDT) is a new promising tactic. It is a gentle in situ photochemical reaction in which a photosensitizer (PS) generates reactive oxygen species (ROS) under laser irradiation. In this work, we have demonstrated Chlorin e6 (Ce6) encapsulated charge-conversion polymeric nanoparticles (NPs) for efficiently targeting and killing pathogenic bacteria in a weakly acidic urinary tract infection environment. Owing to the surface charge conversion of NPs in an acidic environment, the NPs exhibited enhanced recognition for Gram-positive (ex. S. aureus) and Gram-negative (ex. E. coli) bacteria due to the charge interaction. Also, those NPs showed significant antibacterial efficacy in vitro with low cytotoxicity. The MIC value of NPs to E. coli is 17.91 μg ml-1, compared with the free Ce6 value of 29.85 μg ml-1. Finally, a mouse acute cystitis model was used to assess the photodynamic therapy effects in urinary tract infections. A significant decline (P < 0.05) in bacterial cells between NPs and free Ce6 occurred in urine after photodynamic therapy treatment. And the plated counting results revealed a remarkable bacterial cells drop (P < 0.05) in the sacrificed bladder tissue. Above all, this nanotechnology strategy opens a new door for the treatment of urinary tract infections with minimal side effects.

  18. Delayed metamorphosis and recurrence of bacterial infection in irradiated Rana clamitans tadpoles

    International Nuclear Information System (INIS)

    Hart, D.R.

    1982-03-01

    X-ray doses of 5 and 10 Gy (1 Gy/min) given to premetamorphic Green Frog (Rana clamitans) tadpoles delayed their metamorphosis relative to unirradiated controls. Previous pathogenic bacterial infections recurred in irradiated animals prior to metamorphic climax. Limited mortality occurred during metamorphic climax, 80-105 days after irradiation

  19. Acute bacterial infections of the lower respiratory tract in children from low-income countries

    NARCIS (Netherlands)

    Fleer, A; Wolf, B.H.M.

    Acute bacterial infection of the lower respiratory tract is a major cause of morbidity and mortality in children and is responsible for 4 million childhood deaths each year. Most of these deaths are caused by pneumonia and occur in the youngest children in the poorest parts of the world. Severe

  20. A predictive model to estimate the risk of serious bacterial infections in febrile infants

    NARCIS (Netherlands)

    Berger, RMF; Berger, MY; vanSteenselMoll, HA; DzoljicDanilovic, G; DerksenLubsen, G

    Low risk criteria have been defined to identify febrile infants unlikely to have serious bacterial infection (SBI). Using these criteria approximately 40% of all febrile infants can be defined as being at low risk. Of the remaining infants (60%) only 10%-20% have an SBI. No adequate criteria exists

  1. Statin Treatment and Mortality in Bacterial Infections – A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Björkhem-Bergman, Linda; Bergman, Peter; Andersson, Jan; Lindh, Jonatan D.

    2010-01-01

    Background Several studies have reported improved survival in severe bacterial infections among statin treated patients. In addition, statins have been ascribed beneficial anti-inflammatory effects. The aim of this study was to evaluate the effect of statin-treatment on mortality in patients with bacterial infections, by means of a systematic review and a meta-analysis. Methodology and Principal Findings Studies investigating the association between statin use and mortality in patients with bacterial disease were identified in a systematic literature review and a meta-analysis was performed to calculate the overall odds ratio of mortality in statin users. The literature search identified 947 citations from which 40 relevant studies were extracted. In all, 15 studies comprising 113 910 patients were included in the final analysis. Statin use was associated with a significantly (pstatin treatment was no longer significant, with an OR of 0.79 (95% CI 0.58–1.07). Conclusion/Significance According to the meta-analysis of observational studies presented here, patients on statin therapy seem to have a better outcome in bacterial infections. However, the association did not reach statistical significance after adjustment for apparent publication bias. Thus, there is a great need for randomised controlled trials investigating the possible beneficial effect of statins in bacterial infections. PMID:20502712

  2. Widespread bacterial infection affecting Rana temporaria tadpoles in mountain areas

    Directory of Open Access Journals (Sweden)

    Rocco Tiberti

    2011-06-01

    Full Text Available Periodic mass die-offs of Rana temporaria tadpole populations have occurred in the ponds of prealpine mountain areas of Brescia (northern Italy since the early 2000s. The author reports some observational data and analytical results from three sites: tadpoles from mortality events had erythema, especially on the legs, suggestive of septicemia. Bacterial culture of these tadpoles revealed Aeromonas hydrophila and Aeromonas sobria, two organisms often associated with Red leg disease. Egg mass counts from 29 pastureland ponds did not revealed breeding activity declines over five years in the Monte Guglielmo area. Aeromonas hydrophila and Aeromonas sobria usually behave as opportunistic bacteria that can become pathogenic after suppression of the immune system by endogenous or exogenous stressors. Thus, a plurality of environmental factors may contribute to mortality events; some of them are discussed, including loss of high altitude breeding ponds resulting in overcrowding and poor water quality in remaining ponds and the presence of other pathogens.

  3. Genome-Wide RNAi Ionomics Screen Reveals New Genes and Regulation of Human Trace Element Metabolism

    OpenAIRE

    Malinouski, Mikalai; Hasan, Nesrin M.; Zhang, Yan; Seravalli, Javier; Lin, Jie; Avanesov, Andrei; Lutsenko, Svetlana; Gladyshev, Vadim N.

    2017-01-01

    Trace elements are essential for human metabolism and dysregulation of their homeostasis is associated with numerous disorders. Here we characterize mechanisms that regulate trace elements in human cells by designing and performing a genome-wide high-throughput siRNA/ionomics screen, and examining top hits in cellular and biochemical assays. The screen reveals high stability of the ionomes, especially the zinc ionome, and yields known regulators and novel candidates. We further uncover fundam...

  4. Differential effects of interleukin-17 receptor signaling on innate and adaptive immunity during central nervous system bacterial infection

    Directory of Open Access Journals (Sweden)

    Vidlak Debbie

    2012-06-01

    Full Text Available Abstract Although IL-17A (commonly referred to as IL-17 has been implicated in the pathogenesis of central nervous system (CNS autoimmune disease, its role during CNS bacterial infections remains unclear. To evaluate the broader impact of IL-17 family members in the context of CNS infection, we utilized IL-17 receptor (IL-17R knockout (KO mice that lack the ability to respond to IL-17, IL-17F and IL-17E (IL-25. In this article, we demonstrate that IL-17R signaling regulates bacterial clearance as well as natural killer T (NKT cell and gamma-delta (γδ T cell infiltrates during Staphylococcus aureus-induced brain abscess formation. Specifically, when compared with wild-type (WT animals, IL-17R KO mice exhibited elevated bacterial burdens at days 7 and 14 following S. aureus infection. Additionally, IL-17R KO animals displayed elevated neutrophil chemokine production, revealing the ability to compensate for the lack of IL-17R activity. Despite these differences, innate immune cell recruitment into brain abscesses was similar in IL-17R KO and WT mice, whereas IL-17R signaling exerted a greater influence on adaptive immune cell recruitment. In particular, γδ T cell influx was increased in IL-17R KO mice at day 7 post-infection. In addition, NK1.1high infiltrates were absent in brain abscesses of IL-17R KO animals and, surprisingly, were rarely detected in the livers of uninfected IL-17R KO mice. Although IL-17 is a key regulator of neutrophils in other infection models, our data implicate an important role for IL-17R signaling in regulating adaptive immunity during CNS bacterial infection.

  5. Placental Inflammatory Changes and Bacterial Infection in Premature Neonates with Respiratory Failure

    Directory of Open Access Journals (Sweden)

    S. A. Perepelitsa

    2012-01-01

    Full Text Available Objective: to reveal a relationship of placental inflammatory changes to bacterial infection in premature neonates with respiratory failure. Material and methods. Bronchoalveolar aspirate was bacteriologically studied in 157 premature neonates with respiratory distress syndrome (NRDS; the total and differential leukocyte counts were measured in their peripheral blood. The levels of the cytokines IL-1^3, IL-4, IL-6, and TNF-a were studied in different biological fluids of mothers and their babies; the placentas were also morphologically examined. Results. An analysis of bacterial cultures from the tracheobronchial tree revealed no growth of bacterial microflora in 61.8% of cases, Enterococcus faecalis and Staphylococcus epidermidis were isolated in 6.4 and 8.3% of the infants, respectively; Staphylococcus haemolyticus, Staphylococcus capitis, Enterobacter agglomerans, and hemolytic group A Streptococcus were seen in 1.9% each; moreover, 1.3% of the newborn infants were found to have Bacillus spp., Staphylococcus aureus, Escherichia coli, Acinetobacter spp., and Serratia marcescens. Other microorganisms and a microbial association were encountered in 8.9% of cases. Placental morphological examination revealed different inflammatory changes concurrent with chronic and acute placental insufficiency. The investigation demonstrated that the maternal peripheral plasma levels of IL-1^, IL-4, IL-6, and TNF-a were within the physiological range at the end of the first period of delivery. The amniotic fluid displayed elevated IL-6 and TNF-a concentrations and normal IL-4 and IL-1e levels, suggesting that there was an intrauterine inflammatory process. Conclusion. Premature birth is associated with various placental inflammatory changes, which causes intrauterine stimulation of macrophages in the chorionic villi. Specific immune defense mechanisms that prevent the development of a fetal infectious process, i.e. the maternal infectious process, may induce

  6. DMPD: Lipopolysaccharide sensing an important factor in the innate immune response toGram-negative bacterial infections: benefits and hazards of LPShypersensitivity. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available se toGram-negative bacterial infections: benefits and hazards of LPShypersensitivity. Freudenberg MA, Tchapt...portant factor in the innate immune response toGram-negative bacterial infections: benefits and hazards of L...une response toGram-negative bacterial infections: benefits and hazards of LPShyp

  7. Accuracy of C - Reactive protein as a bacterial infection marker in critically immunosuppressed patients: A systematic review and meta-analysis.

    Science.gov (United States)

    de Oliveira, Vanessa Martins; Moraes, Rafael Barberena; Stein, Airton Tetelbom; Wendland, Eliana Márcia

    2017-12-01

    There is a need for a better understanding of the role of C-reactive protein (CRP) as a valid marker for the detection of bacterial infections in critically immunosuppressed patients. A high negative predictive value of CRP is also needed to rule out sepsis and bacterial infections in immunocompetent patients. However, few studies have evaluated the performance of CRP in immunocompromised hosts. The aim of the present study was to evaluate the performance of CRP as a marker of infection in critically immunosuppressed patients. The inclusion criterion was immunosuppression for which CRP was used as a bacterial infection marker. Searches were performed in the Cochrane Register, MEDLINE, EMBASE, SCOPUS, Web OF Science, LILACS and CINAHL databases. We applied the Quality Assessment of Diagnostic Accuracy Studies tool 2 (QUADAS 2) to evaluate the quality of the articles and evaluated the test accuracy parameters using hierarchical summary receiver operating characteristic (HSROC) curves and bivariate random effect models. Only 13 of 21 studies produced quantitative results. We analyzed all studies using the random effects method (restricted maximum likelihood) and obtained a joint diagnostic odds ratio (DOR) of 3.04 (95% confidence interval [CI] 1.71-5.40) with heterogeneity (I 2 =91%, Q=181.48, p<0.001). Therefore, a bivariate model was applied. Analyzing the tuberculosis carrier, steroid user, or presence of opportunistic infection subgroups, as described in the proposal, was not possible due to the lack of information on these topics included in the articles. CRP appears to be a good screening tool for sepsis in critically immunosuppressed patients. Submitted PROSPERO 2015: CRD42015019329. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Bacterial Infection of Fly Ovaries Reduces Egg Production and Induces Local Hemocyte Activation

    Science.gov (United States)

    Brandt, Stephanie M.; Schneider, David S.

    2009-01-01

    Summary Morbidity, the state of being diseased, is an important aspect of pathogenesis that has gone relatively unstudied in fruit flies. Our interest is in characterizing how bacterial pathogenesis affects various physiologies of the fly. We chose to examine the fly ovary because we found bacterial infection had a striking effect on fly reproduction. We observed decreased egg laying after bacterial infection that correlated with increased bacterial virulence. We also found that bacteria colonized the ovary in a previously undescribed manner; bacteria were found in the posterior of the ovary, adjacent to the lateral oviduct. This local infection in the ovary resulted in melanization and activation of the cellular immune response at the site of infection. PMID:17400292

  9. Viral infection of the pregnant cervix predisposes to ascending bacterial infection

    Science.gov (United States)

    Racicot, Karen; Cardenas, Ingrid; Wünsche, Vera; Aldo, Paulomi; Guller, Seth; Means, Robert; Romero, Roberto; Mor, Gil

    2014-01-01

    Preterm birth is the major cause of neonatal mortality and morbidity, and bacterial infections that ascend from the lower female reproductive tract (FRT) are the most common route of uterine infection leading to preterm birth. The uterus and growing fetus are protected from ascending infection by the cervix, which controls and limits microbial access by the production of mucus, cytokines and anti-microbial peptides (AMPs). If this barrier is compromised, bacteria may enter the uterine cavity leading to preterm birth. Using a mouse model, we demonstrate, for the first time, that viral infection of the cervix, during pregnancy, reduces the capacity of the FRT to prevent bacterial infection of the uterus. This is due to differences in susceptibility of the cervix to infection by virus during pregnancy and the associated changes in TLR and AMP expression and function. We suggest that preterm labor is a polymicrobial disease, which requires a multifactorial approach for its prevention and treatment. PMID:23752614

  10. Procalcitonin Identifies Cell Injury, Not Bacterial Infection, in Acute Liver Failure.

    Directory of Open Access Journals (Sweden)

    Jody A Rule

    Full Text Available Because acute liver failure (ALF patients share many clinical features with severe sepsis and septic shock, identifying bacterial infection clinically in ALF patients is challenging. Procalcitonin (PCT has proven to be a useful marker in detecting bacterial infection. We sought to determine whether PCT discriminated between presence and absence of infection in patients with ALF.Retrospective analysis of data and samples of 115 ALF patients from the United States Acute Liver Failure Study Group randomly selected from 1863 patients were classified for disease severity and ALF etiology. Twenty uninfected chronic liver disease (CLD subjects served as controls.Procalcitonin concentrations in most samples were elevated, with median values for all ALF groups near or above a 2.0 ng/mL cut-off that generally indicates severe sepsis. While PCT concentrations increased somewhat with apparent liver injury severity, there were no differences in PCT levels between the pre-defined severity groups-non-SIRS and SIRS groups with no documented infections and Severe Sepsis and Septic Shock groups with documented infections, (p = 0.169. PCT values from CLD patients differed from all ALF groups (median CLD PCT value 0.104 ng/mL, (p ≤0.001. Subjects with acetaminophen (APAP toxicity, many without evidence of infection, demonstrated median PCT >2.0 ng/mL, regardless of SIRS features, while some culture positive subjects had PCT values <2.0 ng/mL.While PCT appears to be a robust assay for detecting bacterial infection in the general population, there was poor discrimination between ALF patients with or without bacterial infection presumably because of the massive inflammation observed. Severe hepatocyte necrosis with inflammation results in elevated PCT levels, rendering this biomarker unreliable in the ALF setting.

  11. Tracking bacterial infection into macrophages by a novel red-emission pH sensor

    OpenAIRE

    Jin, Yuguang; Tian, Yanqing; Zhang, Weiwen; Jang, Sei-Hum; Jen, Alex K.-Y.; Meldrum, Deirdre R.

    2010-01-01

    The relationship between bacteria and host phagocytic cells is a key to the induction of immunity. To visualize and monitor bacterial infection, we developed a novel bacterial membrane permeable pH sensor for noninvasive monitoring of bacterial entry into murine macrophages. The pH sensor was constructed using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) as an electron-withdrawing group and aniline as an electron donating group. A piperazine moiety was u...

  12. Different sterilization methods for overcoming internal bacterial infection in sunflower seeds

    Directory of Open Access Journals (Sweden)

    Taški-Ajduković Ksenija J.

    2005-01-01

    Full Text Available During culture of protoplasts in agarose droplets, permanent problem was bacterial infection. It was assumed that the seeds are the origin of infection, so different sterilization methods were tested in order to overcome this problem. Germination, infection of seeds and hypocotyls and their growth were examined. Based on these parameters, the best result was obtained with the combined use of 5% commercial bleach and dry heating at 45°C.

  13. Ischaemia-modified albumin: a marker of bacterial infection in hospitalized patients with cirrhosis.

    Science.gov (United States)

    Giannone, Ferdinando A; Domenicali, Marco; Baldassarre, Maurizio; Bartoletti, Michele; Naldi, Marina; Laggetta, Maristella; Bertucci, Carlo; Colecchia, Antonio; Viale, Pierluigi; Bernardi, Mauro; Caraceni, Paolo

    2015-11-01

    Patients with cirrhosis present structural changes of human serum albumin (HSA) affecting non-oncotic functions. Ischaemia-modified albumin (IMA), which reflects the capacity to bind cobalt, has been associated to patient mortality during acute-on-chronic liver failure. This study aimed to assess whether circulating IMA is elevated in advanced cirrhosis and its relationship with severity of cirrhosis and specific complications. A total of 127 cirrhotic patients hospitalized for an acute complication of the disease and 44 healthy controls were enrolled. Plasma IMA and IMA to albumin ratio (IMAr) were measured with a cobalt-binding assay. HSA isoforms carrying post-transcriptional molecular changes were assessed with HPLC-ESI-MS. The effect of endotoxemia on IMA was evaluated in rats with CCl4 -cirrhosis. IMA/IMAr is significantly higher in cirrhotic patients than in controls, but no correlations were found with prognostic scores. IMA did not correlate with the altered HSA isoforms. Ascites, renal impairment and hepatic encephalopathy did not influence IMA/IMAr levels. In contrast, IMA/IMAr is significantly higher in infected than non-infected patients. ROC curves showed that IMA/IMAr had similar discriminating performances for bacterial infection as C-reactive protein (CRP). Moreover, CRP and IMA were independently associated with bacterial infection. Consistently, endotoxin injection significantly increased IMA in cirrhotic, but not in healthy rats. IMA is elevated in patients with advanced cirrhosis. The IMA level does not correlate with disease severity scores, but it is specifically associated to bacterial infection, showing a discriminating performance similar to CRP. Further investigations to assess IMA as a novel diagnostic test for bacterial infection are advocated. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Comparative study of bacterial infection prevalence between cirrhotic patients with and without upper gastrointestinal bleeding

    Directory of Open Access Journals (Sweden)

    Delvone Almeida

    Full Text Available Bacterial infection is a frequent complication in patients with chronic liver disease, mainly during the advanced stages. There is evidence that the main factors that contribute to a predisposition to infection in cirrhotic patients are related to hepatic failure with consequent immunodeficiency. Invasive procedures (diagnostic or therapeutic can predispose to bacterial infections, and upper gastrointestinal bleeding (UGB is considered a potentially important risk factor. A group of cirrhotic patients (child B and C Pugh groups were evaluated retrospectively by chart reviews regarding the prevalence of bacterial infection during hospitalization to determine whether UGB was a risk factor. An infection was considered present if a specific organ system was identified or if fever (>38ºC persisted for more than 24 hours with associated leukocytosis. Spontaneous bacterial peritonitis was based on classical criteria. Eighty-nine patients were evaluated. Fourty-six patients presented with UGB, and 43 patients had no UGB (control. There were infections recorded in 25/46 (54% patients with UGB, and 15/43 (35% in those without UGB (p=0.065. The ratio of the number of infections/admitted patients, was significantly larger in the group with UGB (0.78 ± 0.89 vs. 0.39 ± 0.62; p=0.028 since patients had more than one infection. In the UGB group compared to non UGB group, ascites was more frequent (67% vs. 42%; p=0.027; they were more likely to have undergone endoscopic procedures (p<0.001 and the mean ± SD for platelets count was smaller (96,114 ± 57,563 vs. 145,674 ± 104,083; p=0.007. The results show that UGB is an important contribution to bacterial infection among Child B and C cirrhotic patients.

  15. Getting “Inside” Type I IFNs: Type I IFNs in Intracellular Bacterial Infections

    Directory of Open Access Journals (Sweden)

    Deann T. Snyder

    2017-01-01

    Full Text Available Type I interferons represent a unique and complex group of cytokines, serving many purposes during innate and adaptive immunity. Discovered in the context of viral infections, type I IFNs are now known to have myriad effects in infectious and autoimmune disease settings. Type I IFN signaling during bacterial infections is dependent on many factors including whether the infecting bacterium is intracellular or extracellular, as different signaling pathways are activated. As such, the repercussions of type I IFN induction can positively or negatively impact the disease outcome. This review focuses on type I IFN induction and downstream consequences during infection with the following intracellular bacteria: Chlamydia trachomatis, Listeria monocytogenes, Mycobacterium tuberculosis, Salmonella enterica serovar Typhimurium, Francisella tularensis, Brucella abortus, Legionella pneumophila, and Coxiella burnetii. Intracellular bacterial infections are unique because the bacteria must avoid, circumvent, and even co-opt microbial “sensing” mechanisms in order to reside and replicate within a host cell. Furthermore, life inside a host cell makes intracellular bacteria more difficult to target with antibiotics. Because type I IFNs are important immune effectors, modulating this pathway may improve disease outcomes. But first, it is critical to understand the context-dependent effects of the type I IFN pathway in intracellular bacterial infections.

  16. Elevated phenylalanine on newborn screening: follow-up testing may reveal undiagnosed galactosaemia.

    Science.gov (United States)

    Shakespeare, Lynette; Downing, Melanie; Allen, Joyce; Casbolt, Ann-Marie; Ellin, Sheila; Maloney, Martin; Race, Gillian; Bonham, Jim

    2010-11-01

    Introduction Newborn screening for phenylketonuria (PKU) can reveal other conditions which lead to an increased blood spot phenylalanine (Phe) concentration. We have investigated the proportion of blood spot samples that gave a positive screen due to clinically significant conditions other than PKU, compared the positive predictive value (PPV) of our referral Phe cut-off with that recommended by the UK Newborn Screening Programme Centre (UKNSPC) (>210 and >240 μmol/L, respectively) and evaluated the effectiveness of reflex testing for galactosaemia using a lower blood spot Phe cut-off concentration of 130 μmol/L. All blood spot samples that screened positive, for an increased Phe concentration, between April 2001 and March 2008, were identified from the records of the Sheffield Newborn Screening Laboratory and the diagnoses noted. In addition, all cases of galactosaemia detected in or notified to our screening laboratory within this time were also examined and the screened Phe concentrations compared. Out of 438,674 babies who were screened, 67 had Phe concentration >210 μmol/L (15 per 100,000). Of these, 40 had PKU or persistent hyperphenylalaninaemia with a Phe concentration identified by screening between 270 and 2350 μmol/L. A further 11 were diagnosed with another clinically significant disorder: galactosaemia (n = 8), biopterin defects (n = 2), tyrosinaemia Type 1 (n = 1). In addition, 16 had transient elevations in Phe. In total, nine cases of galactosaemia were identified, of whom, three had Phe concentrations 240 μmol/L) will not affect the detection rate of classical PKU, but will improve the PPV from 76% to 80%. The use of a lower cut-off (130 μmol/L) for reflex galactosaemia testing enables the timely identification of asymptomatic cases that benefit particularly from early treatment, without prompting any unnecessary clinical referrals or delaying any referrals. This intervention may reduce mortality in this vulnerable group.

  17. Genomic library screening for viruses from the human dental plaque revealed pathogen-specific lytic phage sequences.

    Science.gov (United States)

    Al-Jarbou, Ahmed Nasser

    2012-01-01

    Bacterial pathogenesis presents an astounding arsenal of virulence factors that allow them to conquer many different niches throughout the course of infection. Principally fascinating is the fact that some bacterial species are able to induce different diseases by expression of different combinations of virulence factors. Nevertheless, studies aiming at screening for the presence of bacteriophages in humans have been limited. Such screening procedures would eventually lead to identification of phage-encoded properties that impart increased bacterial fitness and/or virulence in a particular niche, and hence, would potentially be used to reverse the course of bacterial infections. As the human oral cavity represents a rich and dynamic ecosystem for several upper respiratory tract pathogens. However, little is known about virus diversity in human dental plaque which is an important reservoir. We applied the culture-independent approach to characterize virus diversity in human dental plaque making a library from a virus DNA fraction amplified using a multiple displacement method and sequenced 80 clones. The resulting sequence showed 44% significant identities to GenBank databases by TBLASTX analysis. TBLAST homology comparisons showed that 66% was viral; 18% eukarya; 10% bacterial; 6% mobile elements. These sequences were sorted into 6 contigs and 45 single sequences in which 4 contigs and a single sequence showed significant identity to a small region of a putative prophage in the Corynebacterium diphtheria genome. These findings interestingly highlight the uniqueness of over half of the sequences, whilst the dominance of a pathogen-specific prophage sequences imply their role in virulence.

  18. A functional genomics screen in planarians reveals regulators of whole-brain regeneration

    Science.gov (United States)

    Roberts-Galbraith, Rachel H; Brubacher, John L; Newmark, Phillip A

    2016-01-01

    Planarians regenerate all body parts after injury, including the central nervous system (CNS). We capitalized on this distinctive trait and completed a gene expression-guided functional screen to identify factors that regulate diverse aspects of neural regeneration in Schmidtea mediterranea. Our screen revealed molecules that influence neural cell fates, support the formation of a major connective hub, and promote reestablishment of chemosensory behavior. We also identified genes that encode signaling molecules with roles in head regeneration, including some that are produced in a previously uncharacterized parenchymal population of cells. Finally, we explored genes downregulated during planarian regeneration and characterized, for the first time, glial cells in the planarian CNS that respond to injury by repressing several transcripts. Collectively, our studies revealed diverse molecules and cell types that underlie an animal’s ability to regenerate its brain. DOI: http://dx.doi.org/10.7554/eLife.17002.001 PMID:27612384

  19. Dual gene activation and knockout screen reveals directional dependencies in genetic networks. | Office of Cancer Genomics

    Science.gov (United States)

    Understanding the direction of information flow is essential for characterizing how genetic networks affect phenotypes. However, methods to find genetic interactions largely fail to reveal directional dependencies. We combine two orthogonal Cas9 proteins from Streptococcus pyogenes and Staphylococcus aureus to carry out a dual screen in which one gene is activated while a second gene is deleted in the same cell. We analyze the quantitative effects of activation and knockout to calculate genetic interaction and directionality scores for each gene pair.

  20. Acute Sleep Deprivation Enhances Post-Infection Sleep and Promotes Survival during Bacterial Infection in Drosophila

    Science.gov (United States)

    Kuo, Tzu-Hsing; Williams, Julie A.

    2014-01-01

    Study Objectives: Sleep is known to increase as an acute response to infection. However, the function of this behavioral response in host defense is not well understood. To address this problem, we evaluated the effect of acute sleep deprivation on post-infection sleep and immune function in Drosophila. Setting: Laboratory. Participants: Drosophila melanogaster. Methods and Results: Flies were subjected to sleep deprivation before (early DEP) or after (late DEP) bacterial infection. Relative to a non-deprived control, flies subjected to early DEP had enhanced sleep after infection as well as increased bacterial clearance and survival outcome. Flies subjected to late DEP experienced enhanced sleep following the deprivation period, and showed a modest improvement in survival outcome. Continuous DEP (early and late DEP) throughout infection also enhanced sleep later during infection and improved survival. However, improved survival in flies subjected to late or continuous DEP did not occur until after flies had experienced sleep. During infection, both early and late DEP enhanced NFκB transcriptional activity as measured by a luciferase reporter (κB-luc) in living flies. Early DEP also increased NFκB activity prior to infection. Flies that were deficient in expression of either the Relish or Dif NFκB transcription factors showed normal responses to early DEP. However, the effect of early DEP on post-infection sleep and survival was abolished in double mutants, which indicates that Relish and Dif have redundant roles in this process. Conclusions: Acute sleep deprivation elevated NFκB-dependent activity, increased post-infection sleep, and improved survival during bacterial infection. Citation: Kuo TH, Williams JA. Acute sleep deprivation enhances post-infection sleep and promotes survival during bacterial infection in Drosophila. SLEEP 2014;37(5):859-869. PMID:24790264

  1. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection

    Energy Technology Data Exchange (ETDEWEB)

    Golda-Cepa, M., E-mail: golda@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Syrek, K. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Brzychczy-Wloch, M. [Department of Bacteriology, Microbial Ecology and Parasitology, Jagiellonian University Medical College, Czysta 18, 31-121 Krakow (Poland); Sulka, G.D. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Kotarba, A., E-mail: kotarba@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland)

    2016-09-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function–bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces. - Highlights: • The correlation between work function and bacteria adhesion was discovered. • The discovered correlation is rationalized in terms of electrostatic bacteria–surface repulsion. • The results provide basis for the simple evaluation of implant surfaces against infection.

  2. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection

    International Nuclear Information System (INIS)

    Golda-Cepa, M.; Syrek, K.; Brzychczy-Wloch, M.; Sulka, G.D.; Kotarba, A.

    2016-01-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function–bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces. - Highlights: • The correlation between work function and bacteria adhesion was discovered. • The discovered correlation is rationalized in terms of electrostatic bacteria–surface repulsion. • The results provide basis for the simple evaluation of implant surfaces against infection.

  3. Cytokine patterns in paediatric patients presenting serious gastrointestinal and respiratory bacterial infections

    Science.gov (United States)

    Palacios-Martínez, Monika; Rodríguez-Cruz, Leonor; Cortés-Bejar, Consuelo Del Carmen; Valencia-Chavarría, Fernando; Martínez-Gómez, Daniel; González-Torres, María Cristina

    2014-01-01

    In the adaptive immune response, the types of cytokines produced define whether there is a cellular (T1) or a humoral (T2) response. Specifically, in the T1 response, interleukin 2 (IL-2), interferon γ (IFN-γ) and tumor necrosis factor β (TNF-β) are produced, whereas in the T2 response, IL-4, IL-5, IL- 6, IL-10 and IL-13 are primarily produced. Cytokines are primarily involved in the regulation of immune system cells. The aim of the present study was to evaluate the cytokine patterns (Type 1/Type 2) and TNF-α expression levels in children with severe gastrointestinal and respiratory bacterial infections. The enzyme-linked immunosorbent assay (ELISA) technique was used to identify the cytokines and the infectious agents. The results obtained demonstrated that, in general, children with bacterial infections experienced an increase in IL-2, IFN-γ and IL-4 concentrations and a decrease in TNF-α, IL-5 and IL-6 concentrations when compared to healthy children. Specifically, type 1 cytokines and an increased TNF-α concentration were found in children with gastrointestinal infections. However, patients with respiratory infections showed increased concentrations of both T2 (IL-4, IL-6 and IL-10) and T1 (IL-2 and IFN-γ) components. Thus, it was concluded that children with gastrointestinal infections exclusively developed a T1 response, whereas children with respiratory infections developed a T1/T2 response to fight the infection. PMID:26155128

  4. Rock bream (Oplegnathus fasciatus) IL-12p40: identification, expression, and effect on bacterial infection.

    Science.gov (United States)

    Zhang, Lu; Zhang, Bao-Cun; Hu, Yong-Hua

    2014-08-01

    IL-12p40, also called IL-12β, is a subunit of the proinflammatory cytokines interleukin (IL)-12 and IL-23. In teleost, IL-12p40 homologues have been identified in several species, however, the biological function of fish IL-12p40 is essentially unknown. In this work, we reported the identification and analysis of an IL-12p40, OfIL-12p40, from rock bream (Oplegnathus fasciatus). OfIL-12p40 is composed of 361 amino acids and possesses a conserved IL-12p40 domain and a WSxWS signature motif characteristic of known IL-12p40. Constitutive expression of OfIL-12p40 occurred in multiple tissues and was highest in kidney. Experimental infection with bacterial pathogen upregulated the expression of OfIL-12p40 in kidney and spleen in a time-dependent manner. Purified recombinant OfIL-12p40 (rOfIL-12p40) stimulated the respiratory burst activity of peripheral blood leukocytes in a dose-dependent manner. rOfIL-12p40 also enhanced the resistance of rock bream against bacterial infection and upregulated the expression of innate immune genes in kidney. Taken together, these results indicate that OfIL-12p40 possesses cytokine-like property and plays a role in immune defense against bacterial infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

    Science.gov (United States)

    Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

    2017-07-01

    We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  6. Cognitive-behavioral screening reveals prevalent impairment in a large multicenter ALS cohort.

    Science.gov (United States)

    Murphy, Jennifer; Factor-Litvak, Pam; Goetz, Raymond; Lomen-Hoerth, Catherine; Nagy, Peter L; Hupf, Jonathan; Singleton, Jessica; Woolley, Susan; Andrews, Howard; Heitzman, Daragh; Bedlack, Richard S; Katz, Jonathan S; Barohn, Richard J; Sorenson, Eric J; Oskarsson, Björn; Fernandes Filho, J Americo M; Kasarskis, Edward J; Mozaffar, Tahseen; Rollins, Yvonne D; Nations, Sharon P; Swenson, Andrea J; Koczon-Jaremko, Boguslawa A; Mitsumoto, Hiroshi

    2016-03-01

    To characterize the prevalence of cognitive and behavioral symptoms using a cognitive/behavioral screening battery in a large prospective multicenter study of amyotrophic lateral sclerosis (ALS). Two hundred seventy-four patients with ALS completed 2 validated cognitive screening tests and 2 validated behavioral interviews with accompanying caregivers. We examined the associations between cognitive and behavioral performance, demographic and clinical data, and C9orf72 mutation data. Based on the ALS Cognitive Behavioral Screen cognitive score, 6.5% of the sample scored below the cutoff score for frontotemporal lobar dementia, 54.2% scored in a range consistent with ALS with mild cognitive impairment, and 39.2% scored in the normal range. The ALS Cognitive Behavioral Screen behavioral subscale identified 16.5% of the sample scoring below the dementia cutoff score, with an additional 14.1% scoring in the ALS behavioral impairment range, and 69.4% scoring in the normal range. This investigation revealed high levels of cognitive and behavioral impairment in patients with ALS within 18 months of symptom onset, comparable to prior investigations. This investigation illustrates the successful use and scientific value of adding a cognitive-behavioral screening tool in studies of motor neuron diseases, to provide neurologists with an efficient method to measure these common deficits and to understand how they relate to key clinical variables, when extensive neuropsychological examinations are unavailable. These tools, developed specifically for patients with motor impairment, may be particularly useful in patient populations with multiple sclerosis and Parkinson disease, who are known to have comorbid cognitive decline. © 2016 American Academy of Neurology.

  7. [Transfusion-transmitted bacterial infection of a apheresis platelet concentrate with Streptococcus gallolyticus: Analysis of one case].

    Science.gov (United States)

    Le Niger, C; Dalbies, F; Narbonne, V; Hery-Arnaud, G; Virmaux, M; Léostic, C; Hervé, F; Liétard, C

    2014-06-01

    Bacterial infections are uncommon complications of the blood products transfusion but they are potentially serious. Many advances have been done over the past few years to guarantee the microbiological security of blood products as the donors selection with a medical talk, the derivation of the first 30 millilitres blood during the donation, the deleucocytation of blood products… But in spite of these advances, cases of bacterial infection always remain. The purpose of this study was to point out the platelet concentrate's transfusion-transmitted bacterial infection with Streptococcus gallolyticus and the unusual consequence for the donor by uncovering an asymptomatic rectal neoplastic tumor. This study as raised as to whether the usefulness of systematic bacterial inactivation in the platelets concentrates. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  8. Liver is the major source of elevated serum lipocalin-2 levels after bacterial infection or partial hepatectomy

    DEFF Research Database (Denmark)

    Xu, Ming-Jiang; Feng, Dechun; Wu, Hailong

    2015-01-01

    cell type responsible for LCN2 production after bacterial infection or PHx, and this response is dependent on IL-6 activation of the STAT3 signaling pathway. Thus, hepatocyte-derived LCN2 plays an important role in inhibiting bacterial infection and promoting liver regeneration....... or E. coli. These mice also had increased enteric bacterial translocation from the gut to the mesenteric lymph nodes and exhibited reduced liver regeneration after PHx. Treatment with interleukin (IL)-6 stimulated hepatocytes to produce LCN2 in vitro and in vivo. Hepatocyte-specific ablation of the IL...

  9. Polymer-Ag nanocomposites with enhanced antimicrobial activity against bacterial infection.

    Science.gov (United States)

    Mei, Lin; Lu, Zhentan; Zhang, Xinge; Li, Chaoxing; Jia, Yanxia

    2014-09-24

    Herein, a nontoxic nanocomposite is synthesized by reduction of silver nitrate in the presence of a cationic polymer displaying strong antimicrobial activity against bacterial infection. These nanocomposites with a large concentration of positive charge promote their adsorption to bacterial membranes through electrostatic interaction. Moreover, the synthesized nanocomposites with polyvalent and synergistic antimicrobial effects can effectively kill both Gram-positive and Gram-negative bacteria without the emergence of bacterial resistance. Morphological changes obtained by transmission electron microscope observation show that these nanocomposites can cause leakage and chaos of intracellular contents. Analysis of the antimicrobial mechanism confirms that the lethal action of nanocomposites against the bacteria started with disruption of the bacterial membrane, subsequent cellular internalization of the nanoparticles, and inhibition of intracellular enzymatic activity. This novel antimicrobial material with good cytocompatibility promotes healing of infected wounds in diabetic rats, and has a promising future in the treatment of other infectious diseases.

  10. M13 virus based detection of bacterial infections in living hosts.

    Science.gov (United States)

    Bardhan, Neelkanth M; Ghosh, Debadyuti; Belcher, Angela M

    2014-08-01

    We report a first method for using M13 bacteriophage as a multifunctional scaffold for optically imaging bacterial infections in vivo. We demonstrate that M13 virus conjugated with hundreds of dye molecules (M13-Dye) can target and distinguish pathogenic infections of F-pili expressing and F-negative strains of E. coli. Further, in order to tune this M13-Dye complex suitable for targeting other strains of bacteria, we have used a 1-step reaction for creating an anti-bacterial antibody-M13-Dye probe. As an example, we show anti-S. aureus-M13-Dye able to target and image infections of S. aureus in living hosts, with a 3.7× increase in fluorescence over background. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Use of Multiplex PCR for Diagnosis of Bacterial Infection Respiratory Mixed

    Directory of Open Access Journals (Sweden)

    Al-ssum, R. M.

    2010-01-01

    Full Text Available Atypical bacteria grow very slowly in culture or they do not grow at all leading to delays in detection and diagnosis. PCR multiplex was performed on template DNAs extracted from seventy three collected specimens. Thirty seven showed positive indication for the presence of bacterial infection. The incidence of Mycoplasma pneumoniae, Chlamydia pneumonia and Legionella pneumophila as a single infecting agent was 31.5%, 27.5% and 20 % respectively. Dual agent infection caused by Mycoplasma + Chlamydia, Mycoplasma + Legionella and Legionella + Chlamydia was 24%, 20% and 15% respectively. Triple agent infection caused by Legionella + Mycoplasma + Chlamydia was 17.5%. The etiology of the infection was M. pneumoniae, L. pneumophila or C. pneumoniae as a single etiology or in combination of two or three organisms.

  12. A novel 3D skin explant model to study anaerobic bacterial infection

    DEFF Research Database (Denmark)

    Maboni, Grazieli; Davenport, Rebecca; Sessford, Kate

    2017-01-01

    of the tissue structure and the cell types present in the host environment. A 3D skin culture model can be set up using tissues acquired from surgical procedures or post slaughter, making it a cost effective and attractive alternative to animal experimentation. The majority of 3D culture models have been......Skin infection studies are often limited by financial and ethical constraints, and alternatives, such as monolayer cell culture, do not reflect many cellular processes limiting their application. For a more functional replacement, 3D skin culture models offer many advantages such as the maintenance...... bacterium and the causative agent of footrot. The mechanism of infection and host immune response to D. nodosus is poorly understood. Here we present a novel 3D skin ex vivo model to study anaerobic bacterial infections using ovine skin explants infected with D. nodosus. Our results demonstrate that D...

  13. Hindlimb suspension and SPE-like radiation impairs clearance of bacterial infections.

    Directory of Open Access Journals (Sweden)

    Minghong Li

    Full Text Available A major risk of extended space travel is the combined effects of weightlessness and radiation exposure on the immune system. In this study, we used the hindlimb suspension model of microgravity that includes the other space stressors, situational and confinement stress and alterations in food intake, and solar particle event (SPE-like radiation to measure the combined effects on the ability to control bacterial infections. A massive increase in morbidity and decrease in the ability to control bacterial growth was observed using 2 different types of bacteria delivered by systemic and pulmonary routes in 3 different strains of mice. These data suggest that an astronaut exposed to a strong SPE during extended space travel is at increased risk for the development of infections that could potentially be severe and interfere with mission success and astronaut health.

  14. Rapid and widely disseminated acute phase protein response after experimental bacterial infection of pigs

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Mortensen, Shila; Boye, Mette

    2009-01-01

    The acute phase protein response is a well-described generalized early host response to tissue injury, inflammation and infection, observed as pronounced changes in the concentrations of a number of circulating serum proteins. The biological function of this response and its interplay with other...... parts of innate host defence reactions remain somewhat elusive. In order to gain new insight into this early host defence response in the context of bacterial infection we studied gene expression changes in peripheral lymphoid tissues as compared to hepatic expression changes, 14-18 h after lung...... with measurements of interleukin-6 and selected acute phase proteins in serum. C-reactive protein and serum amyloid A were clearly induced 14-18 h after infection. Extrahepatic expression of acute phase proteins was found to be dramatically altered as a result of the lung infection with an extrahepatic acute phase...

  15. Procalcitonin and C-reactive protein as markers of bacterial infection in patients with solid tumours

    DEFF Research Database (Denmark)

    Diness, Laura V; Maraldo, Maja V; Mortensen, Christiane E

    2014-01-01

    INTRODUCTION: The diagnosis of bacterial infections in patients with solid tumours can be difficult as both the tumour and its treatment can cause symptoms and signs similar to those of infections. Many patients with solid tumours therefore receive antibiotic treatment without having a bacterial......, but with no signs of infection. RESULTS: Of the 41 admitted patients, 25 were classified as having an infection (either microbiologically or radioo-gically verified). Among the 25 cases with infection, PCT was within the normal range in 11 cases and only elevated in 14. As nearly half of the patients with infection...... had PCT within the normal range, PCT is not suited to exclude an infection. CRP was elevated in 20 patients out of the 25. CONCLUSION: PCT within the normal range cannot exclude an infection and does not appear to be superior to CRP to exclude an infection in patients with solid tumours. FUNDING...

  16. Synthesis and biodistribution of 99mTc-Vancomycin in a model of bacterial infection

    International Nuclear Information System (INIS)

    Roohi, S.; Mushtaq, A.; Malik, S.A.

    2005-01-01

    Vancomycin Hydrochloride is an antibiotic produced by the growth of certain strains of Streptomyces orientalis. As vancomycin hydrochloride is poorly absorbed after oral administration; it is given intravenously for therapy of systemic infections. Vancomycin was labeled with technetium-99m pertechnetate using SnCl 2 . 2H 2 O as reducing agent. The labeling efficiency depends on ligand/reductant ratio, pH, and volume of reaction mixture. Radiochemical purity and stability of 99m Tc-Vancomycin was determined by thin layer chromatography. Biodistribution studies of 99m Tc-Vancomycin were performed in a model of bacterial infection in Sprague-Dawley rats. A significantly higher accumulation of 99m Tc-Vancomycin was seen at sites of S. aureus infected animals. Whereas uptake of 99m Tc-Vancomycin in turpentine inflamed rats were quite low. (orig.)

  17. Osteomyelitis in a Paleozoic reptile: ancient evidence for bacterial infection and its evolutionary significance

    Science.gov (United States)

    Reisz, Robert R.; Scott, Diane M.; Pynn, Bruce R.; Modesto, Sean P.

    2011-06-01

    We report on dental and mandibular pathology in Labidosaurus hamatus, a 275 million-year-old terrestrial reptile from North America and associate it with bacterial infection in an organism that is characterized by reduced tooth replacement. Analysis of the surface and internal mandibular structure using mechanical and CT-scanning techniques permits the reconstruction of events that led to the pathology and the possible death of the individual. The infection probably occurred as a result of prolonged exposure of the dental pulp cavity to oral bacteria, and this exposure was caused by injury to the tooth in an animal that is characterized by reduced tooth replacement cycles. In these early reptiles, the reduction in tooth replacement is an evolutionary innovation associated with strong implantation and increased oral processing. The dental abscess observed in L. hamatus, the oldest known infection in a terrestrial vertebrate, provides clear evidence of the ancient association between terrestrial vertebrates and their oral bacteria.

  18. Diagnostic markers of serious bacterial infections in febrile infants younger than 90 days old.

    Science.gov (United States)

    Nosrati, Adi; Ben Tov, Amir; Reif, Shimon

    2014-02-01

    The aim of this study was to assess correlations between demographic, clinical and laboratory characteristics and the risk of serious bacterial infection (SBI) in febrile urinary tract infection (43 infants; 90% of all SBI), three infants had bacteremia, one had bacterial pneumonia and one had bacterial meningitis. Significant independent clinical predictors for the diagnosis of SBI included duration of fever, absence of rhinitis and the absence of lung and skin manifestations. Significant independent laboratory predictors were absolute neutrophil count (ANC), platelets, blood urea nitrogen and C-reactive protein (CRP) level. On receiver operating characteristic curve analysis, the CRP area under the curve (0.819) was significantly superior to ANC and leukocyte count. Of the clinical and laboratory variables selected for evaluation, qualitative CRP was the strongest independent predictor for diagnosing SBI and a significantly better diagnostic marker than clinical characteristics, ANC and white blood cell count. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

  19. Co-trimoxazole alone for prevention of bacterial infection in patients with acute leukaemia.

    Science.gov (United States)

    Starke, I D; Donnelly, P; Catovsky, D; Darrell, J; Johnson, S A; Goldman, J M; Galton, D A

    1982-01-02

    43 patients undergoing treatment for acute leukaemia were randomised to receive either co-trimoxazole alone or co-trimoxazole with framycetin and colistin as antibacterial prophylaxis during periods of neutropenia. There were no significant differences between the two treatment groups in the time before the onset of the first fever, the number of episodes of fever or of septicaemia per patient, the number of neutropenic days during which patients remained afebrile or did not require systemic antibiotics, or the number of resistant organisms acquired. Co-trimoxazole alone is cheaper and easier to take than co-trimoxazole with framycetin and colistin, and it is therefore preferable to the three-drug combination for the prophylaxis of bacterial infection.

  20. Drug repurposing as an alternative for the treatment of recalcitrant bacterial infections

    Directory of Open Access Journals (Sweden)

    Adrian eRangel-Vega

    2015-04-01

    Full Text Available Bacterial infections remain one of the leading causes of death worldwide, and the therapeutic outlook for these infections is worsening, due the rise of antibiotic resistant strains. The pharmaceutical industry has produced few new types of antibiotics in more than a decade. Researchers are taking several approaches towards developing new classes of antibiotics, including (1 focusing on new targets and processes, such as bacterial cell-cell communication that upregulates virulence; (2 designing inhibitors of bacterial resistance, such as blockers of multi-drug efflux pumps; and (3 using alternative antimicrobials such as bacteriophages. In addition, the strategy of finding new uses for existing drugs is beginning to produce results: antibacterial properties have been discovered in existing anticancer, antifungal, anthelmintic, and anti-inflammatory drugs. In this work we discuss the antimicrobial properties of gallium based compounds, 5-fluorouracil, ciclopirox, diflunisal, and some other FDA-approved drugs.

  1. [Strategy for choosing antibiotics for treating bacterial infections associated with chronic tick-borne encephalitis].

    Science.gov (United States)

    Malenko, G V; Pogodina, V V; Frolova, M P; Ivannikova, T A

    1996-01-01

    The capacity of wide-spectrum antibiotics kefzol and ristomycin to activate the persisting tick-borne encephalitis (TBE) virus and cause an exacerbation of chronic process was investigated in Syrian hamsters in whom a prolonged (77 to 270 days) persistent TBE infection was induced by three TBE strains: Vasilchenko, V-383, and 205. The degree of antibiotic-induced activation was assessed using the criteria characterizing the reproduction and peculiarities of persisting TBE virus, immunodepression, and morphologic changes in the central nervous system. Effects of kefzol and ristomycin were compared with those of 8 antibiotics studied previously. Ristomycin, levomycetin (chloramphycin), penicillin, ampicillin (ampital), and levoridan were referred to drugs devoid of evident provoking effect. Kefzol (cefamezin), florimycin (viomycin), and kanamycin (kanamytrex) were characterized as weak activators and streptomycin and tetracycline as potent activators of the persisting TBE virus. These data may be used when selecting alternative agents for therapy of secondary bacterial infections concomitant with TBE.

  2. Value of serum PCT in early diagnosis of bacterial infection in patients with liver failure

    Directory of Open Access Journals (Sweden)

    WANG Chuanmin

    2017-06-01

    Full Text Available ObjectiveTo investigate the value of serum procalcitonin (PCT in early diagnosis of bacterial infection in patients with liver failure. MethodsA total of 463 patients with hepatitis B were selected from January to December, 2014, in the Department of Infectious Diseases, Taihe Hospital. According to the degree of liver injury, the patients were divided into four groups: mild liver injury group (n=120, moderate liver injury group (n=222, sever liver injury group (n=53, and liver failure group (n=68. Serum PCT was measured for all patients, and the white blood cell count (WBC and high-sensitivity C-reactive protein (hsCRP were measured for patients with liver failure. The clinical manifestations were observed and recorded. The t test was used for comparison of normally distributed continuous data, while the Kruskal-Wallis H test was used for non-normally distributed continuous data; the Mann-Whitney U test was used for pairwise comparison of continuous data. The chi-square test was used for comparison of categorical data. The receiver operating characteristic (ROC curve was used for the analysis of predictive value. ResultsThe liver failure group had a significantly higher PCT level than the severe liver injury group, moderate liver injury group, and mild liver injury group (0.81[0.34-2.15] vs 0.53[0.21-1.59], 0.35[010-1.18], and 0.17[0.10-0.60], χ2=25.091, P<0.05. The liver failure patients with PCT levels of <0.25 ng/ml (n=10, 0.25-0.5 ng/ml (n=10, and >0.5 ng/ml (n=48 had infection rates of 20%, 30%, and 66.7%, respectively, with a significant difference between the patients with a PCT level of >0.5 ng/ml and those with PCT levels of <0.25 ng/ml and 0.25-0.5 ng/ml (χ2=5631,4650,P=0018,0031. Among the liver failure patients, the infection cases had significantly higher PCT, WBC, and hsCRP than the non-infection cases (PCT: 3.72±1.33 ng/ml vs 0.34±0.12 ng/ml, t=-2.547, P=0.015; hsCRP: 16.70±7.03 mg

  3. Empiric Antibiotic Use and Susceptibility in Infants With Bacterial Infections: A Multicenter Retrospective Cohort Study.

    Science.gov (United States)

    Feldman, Elana A; McCulloh, Russell J; Myers, Angela L; Aronson, Paul L; Neuman, Mark I; Bradford, Miranda C; Alpern, Elizabeth R; Balamuth, Frances; Blackstone, Mercedes M; Browning, Whitney L; Hayes, Katie; Korman, Rosalynne; Leazer, Rianna C; Nigrovic, Lise E; Marble, Richard; Roben, Emily; Williams, Derek J; Tieder, Joel S

    2017-07-20

    To assess hospital differences in empirical antibiotic use, bacterial epidemiology, and antimicrobial susceptibility for common antibiotic regimens among young infants with urinary tract infection (UTI), bacteremia, or bacterial meningitis. We reviewed medical records from infants <90 days old presenting to 8 US children's hospitals with UTI, bacteremia, or meningitis. We used the Pediatric Health Information System database to identify cases and empirical antibiotic use and medical record review to determine infection, pathogen, and antimicrobial susceptibility patterns. We compared hospital-level differences in antimicrobial use, pathogen, infection site, and antimicrobial susceptibility. We identified 470 infants with bacterial infections: 362 (77%) with UTI alone and 108 (23%) with meningitis or bacteremia. Infection type did not differ across hospitals ( P = .85). Empirical antibiotic use varied across hospitals ( P < .01), although antimicrobial susceptibility patterns for common empirical regimens were similar. A third-generation cephalosporin would have empirically treated 90% of all ages, 89% in 7- to 28-day-olds, and 91% in 29- to 89-day-olds. The addition of ampicillin would have improved coverage in only 4 cases of bacteremia and meningitis. Ampicillin plus gentamicin would have treated 95%, 89%, and 97% in these age groups, respectively. Empirical antibiotic use differed across regionally diverse US children's hospitals in infants <90 days old with UTI, bacteremia, or meningitis. Antimicrobial susceptibility to common antibiotic regimens was similar across hospitals, and adding ampicillin to a third-generation cephalosporin minimally improves coverage. Our findings support incorporating empirical antibiotic recommendations into national guidelines for infants with suspected bacterial infection. Copyright © 2017 by the American Academy of Pediatrics.

  4. Scintigraphic images of bacterial infection using aptamers directly labeled with {sup 99m}Tc

    Energy Technology Data Exchange (ETDEWEB)

    Santos, S.R.; Correa, C.R.; Andrade, A.S.R., E-mail: sararoberta7@hotmail.com, E-mail: crisrcorrea@gmail.com, E-mail: antero@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Barros, A.L.B.; Diniz, S.O.F.; Cardoso, V.N., E-mail: brancodebarros@yahoo.com.br, E-mail: valbertcardoso@yahoo.com.br, E-mail: simoneodilia@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Farmacia. Departamento de Analises Clinicas e Toxicologicas

    2015-07-01

    Staphylococcus aureus is specie of great medical importance and is the most commonly agent found in infections of soft tissues, bone infections and bone prostheses. In this study, aptamers selected to S. aureus were labeled by the direct method with {sup 99m}Tc and used for bacterial infection identification by scintigraphy. The radiolabeled aptamers radiochemical purity and stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice (n=6) were used for the scintigraphic imaging studies. The first group was infected intramuscularly in the right thigh with S. aureus, the second group with C. albicans and the third group received zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (18 MBq) were injected by the tail vein. Scintigraphic images were acquired at 1 h and 4 h postinjection. The radiolabeling yield with {sup 99m}Tc was over 90%. The radiolabeled aptamers were stable in 0.9% saline, plasma and cysteine excess. The scintigraphic image profiles showed high uptake in the kidneys and bladder in all groups, indicating a main renal excretion consistent with the hydrophilic nature of the molecule. No accumulation of radioactivity was observed in the thyroid, stomach, liver and spleen, indicating acceptable levels of radiochemical impurities. The group infected with S. aureus showed a visible uptake in the infected right thigh at 1 h post-injection. For the control groups (C. albicans and zymosan) visible differences between the right and left thighs were not observed. The radiolabeled aptamers were able to distinguish aseptic inflammation from bacterial infection and bacterial from fungal infection. (author)

  5. New prediction model for diagnosis of bacterial infection in febrile infants younger than 90 days.

    Science.gov (United States)

    Vujevic, Matea; Benzon, Benjamin; Markic, Josko

    2017-01-01

    Vujevic M, Benzon B, Markic J. New prediction model for diagnosis of bacterial infection in febrile infants younger than 90 days. Turk J Pediatr 2017; 59: 261-268. Due to non-specific clinical presentation in febrile infants, extensive laboratory testing is often carried out to distinguish simple viral disease from serious bacterial infection (SBI). Objective of this study was to compare efficacy of different biomarkers in early diagnosis of SBI in infants Pediatrics, University Hospital Centre Split with suspicion of having SBI were included in this study. Retrospective cohort analysis of data acquired from medical records was performed. Out of 181 enrolled patients, SBI was confirmed in 70. Most common diagnosis was urinary tract infection (68.6%), followed by pneumonia (12.9%), sepsis (11.4%), gastroenterocolitis (5.7%) and meningitis (1.4%). Male gender was shown to be a risk factor for SBI in this population (p=0.008). White blood cell count (WBC), absolute neutrophil count (ANC) and C-reactive protein (CRP) were confirmed as the independent predictors of SBI, with CRP as the best one. Two prediction models built by combining biomarkers and clinical variables were selected as optimal with sensitivities of 74.3% and 75.7%, and specificities of 88.3% and 86%. Evidently, CRP is a more superior biomarker in diagnostics of SBI comparing to WBC and ANC. Prediction models were shown to be better in predicting SBI than independent biomarkers. Although both showed high sensitivity and specificity, their true strength should be determined using validation cohort.

  6. SECONDARY BACTERIAL INFECTION IN ADULT PATIENTS WITH PROLONGED AND SEVERE DENGUE FEVER

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2016-05-01

    Full Text Available INTRODUCTION Generally, in dengue shock syndrome antibiotics are not advised. But unrecognised bacterial infection is likely to contribute to morbidity and mortality, probably because of increased vascular permeability. OBJECTIVES To assess the incidence of secondary bacterial infection in adult patients with prolonged and severe dengue fever. METHODS A prospective study was conducted recruiting patients with confirmed acute dengue infection who had prolonged fever (>5 days. Prior to institution of antibiotic therapy, two sets of blood cultures were taken from patients. Demographic, clinical, haematological and biochemical parameters were recorded. Severity of fever & associated symptoms assessed. Ultrasonography done to find out development of ascites and pleural effusions. RESULTS Sixty patients (60.0% males with a mean age of 33.5 years (SD 12.1 were studied. The average duration of fever was 6.9 days (SD 1.6. Fifteen patients (25% had bacterial isolates in their blood cultures; Staphylococcus aureus (n=3, coliforms (n=7, pseudomonas (n=2 and 3 had mixed growths. The culture positive group had severe body aches and joints paint at admission and high grade fever, third space fluid accumulation and significant drop in platelets compared to culture-negative group. CONCLUSIONS A quarter of dengue patients with prolonged fever had a bacterial isolate. Culture-positive patients appeared more ill with body aches and had higher degrees of fever during the course of the illness. Increased vascular permeability may predispose to bacterial seepage into blood. Although white cell count is not helpful in detecting bacteraemia in dengue fever, low platelet count and severe symptoms at presentation may be helpful.

  7. Acute sleep deprivation enhances post-infection sleep and promotes survival during bacterial infection in Drosophila.

    Science.gov (United States)

    Kuo, Tzu-Hsing; Williams, Julie A

    2014-05-01

    Sleep is known to increase as an acute response to infection. However, the function of this behavioral response in host defense is not well understood. To address this problem, we evaluated the effect of acute sleep deprivation on post-infection sleep and immune function in Drosophila. Laboratory. Drosophila melanogaster. Flies were subjected to sleep deprivation before (early DEP) or after (late DEP) bacterial infection. Relative to a non-deprived control, flies subjected to early DEP had enhanced sleep after infection as well as increased bacterial clearance and survival outcome. Flies subjected to late DEP experienced enhanced sleep following the deprivation period, and showed a modest improvement in survival outcome. Continuous DEP (early and late DEP) throughout infection also enhanced sleep later during infection and improved survival. However, improved survival in flies subjected to late or continuous DEP did not occur until after flies had experienced sleep. During infection, both early and late DEP enhanced NFκB transcriptional activity as measured by a luciferase reporter (κB-luc) in living flies. Early DEP also increased NFκB activity prior to infection. Flies that were deficient in expression of either the Relish or Dif NFκB transcription factors showed normal responses to early DEP. However, the effect of early DEP on post-infection sleep and survival was abolished in double mutants, which indicates that Relish and Dif have redundant roles in this process. Acute sleep deprivation elevated NFκB-dependent activity, increased post-infection sleep, and improved survival during bacterial infection.

  8. Scintigraphic images of bacterial infection using aptamers directly labeled with 99mTc

    International Nuclear Information System (INIS)

    Santos, S.R.; Correa, C.R.; Andrade, A.S.R.; Barros, A.L.B.; Diniz, S.O.F.; Cardoso, V.N.

    2015-01-01

    Staphylococcus aureus is specie of great medical importance and is the most commonly agent found in infections of soft tissues, bone infections and bone prostheses. In this study, aptamers selected to S. aureus were labeled by the direct method with 99m Tc and used for bacterial infection identification by scintigraphy. The radiolabeled aptamers radiochemical purity and stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice (n=6) were used for the scintigraphic imaging studies. The first group was infected intramuscularly in the right thigh with S. aureus, the second group with C. albicans and the third group received zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (18 MBq) were injected by the tail vein. Scintigraphic images were acquired at 1 h and 4 h postinjection. The radiolabeling yield with 99m Tc was over 90%. The radiolabeled aptamers were stable in 0.9% saline, plasma and cysteine excess. The scintigraphic image profiles showed high uptake in the kidneys and bladder in all groups, indicating a main renal excretion consistent with the hydrophilic nature of the molecule. No accumulation of radioactivity was observed in the thyroid, stomach, liver and spleen, indicating acceptable levels of radiochemical impurities. The group infected with S. aureus showed a visible uptake in the infected right thigh at 1 h post-injection. For the control groups (C. albicans and zymosan) visible differences between the right and left thighs were not observed. The radiolabeled aptamers were able to distinguish aseptic inflammation from bacterial infection and bacterial from fungal infection. (author)

  9. RNAi screen reveals an Abl kinase-dependent host cell pathway involved in Pseudomonas aeruginosa internalization.

    Directory of Open Access Journals (Sweden)

    Julia F Pielage

    2008-03-01

    Full Text Available Internalization of the pathogenic bacterium Pseudomonas aeruginosa by non-phagocytic cells is promoted by rearrangements of the actin cytoskeleton, but the host pathways usurped by this bacterium are not clearly understood. We used RNAi-mediated gene inactivation of approximately 80 genes known to regulate the actin cytoskeleton in Drosophila S2 cells to identify host molecules essential for entry of P. aeruginosa. This work revealed Abl tyrosine kinase, the adaptor protein Crk, the small GTPases Rac1 and Cdc42, and p21-activated kinase as components of a host signaling pathway that leads to internalization of P. aeruginosa. Using a variety of complementary approaches, we validated the role of this pathway in mammalian cells. Remarkably, ExoS and ExoT, type III secreted toxins of P. aeruginosa, target this pathway by interfering with GTPase function and, in the case of ExoT, by abrogating P. aeruginosa-induced Abl-dependent Crk phosphorylation. Altogether, this work reveals that P. aeruginosa utilizes the Abl pathway for entering host cells and reveals unexpected complexity by which the P. aeruginosa type III secretion system modulates this internalization pathway. Our results furthermore demonstrate the applicability of using RNAi screens to identify host signaling cascades usurped by microbial pathogens that may be potential targets for novel therapies directed against treatment of antibiotic-resistant infections.

  10. Novel gene function revealed by mouse mutagenesis screens for models of age-related disease.

    Science.gov (United States)

    Potter, Paul K; Bowl, Michael R; Jeyarajan, Prashanthini; Wisby, Laura; Blease, Andrew; Goldsworthy, Michelle E; Simon, Michelle M; Greenaway, Simon; Michel, Vincent; Barnard, Alun; Aguilar, Carlos; Agnew, Thomas; Banks, Gareth; Blake, Andrew; Chessum, Lauren; Dorning, Joanne; Falcone, Sara; Goosey, Laurence; Harris, Shelley; Haynes, Andy; Heise, Ines; Hillier, Rosie; Hough, Tertius; Hoslin, Angela; Hutchison, Marie; King, Ruairidh; Kumar, Saumya; Lad, Heena V; Law, Gemma; MacLaren, Robert E; Morse, Susan; Nicol, Thomas; Parker, Andrew; Pickford, Karen; Sethi, Siddharth; Starbuck, Becky; Stelma, Femke; Cheeseman, Michael; Cross, Sally H; Foster, Russell G; Jackson, Ian J; Peirson, Stuart N; Thakker, Rajesh V; Vincent, Tonia; Scudamore, Cheryl; Wells, Sara; El-Amraoui, Aziz; Petit, Christine; Acevedo-Arozena, Abraham; Nolan, Patrick M; Cox, Roger; Mallon, Anne-Marie; Brown, Steve D M

    2016-08-18

    Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss.

  11. Genome-Wide RNAi Ionomics Screen Reveals New Genes and Regulation of Human Trace Element Metabolism

    Science.gov (United States)

    Malinouski, Mikalai; Hasan, Nesrin M.; Zhang, Yan; Seravalli, Javier; Lin, Jie; Avanesov, Andrei; Lutsenko, Svetlana; Gladyshev, Vadim N.

    2017-01-01

    Trace elements are essential for human metabolism and dysregulation of their homeostasis is associated with numerous disorders. Here we characterize mechanisms that regulate trace elements in human cells by designing and performing a genome-wide high-throughput siRNA/ionomics screen, and examining top hits in cellular and biochemical assays. The screen reveals high stability of the ionomes, especially the zinc ionome, and yields known regulators and novel candidates. We further uncover fundamental differences in the regulation of different trace elements. Specifically, selenium levels are controlled through the selenocysteine machinery and expression of abundant selenoproteins; copper balance is affected by lipid metabolism and requires machinery involved in protein trafficking and posttranslational modifications; and the iron levels are influenced by iron import and expression of the iron/heme-containing enzymes. Our approach can be applied to a variety of disease models and/or nutritional conditions, and the generated dataset opens new directions for studies of human trace element metabolism. PMID:24522796

  12. A forward genetic screen reveals essential and non-essential RNAi factors in Paramecium tetraurelia

    Science.gov (United States)

    Marker, Simone; Carradec, Quentin; Tanty, Véronique; Arnaiz, Olivier; Meyer, Eric

    2014-01-01

    In most eukaryotes, small RNA-mediated gene silencing pathways form complex interacting networks. In the ciliate Paramecium tetraurelia, at least two RNA interference (RNAi) mechanisms coexist, involving distinct but overlapping sets of protein factors and producing different types of short interfering RNAs (siRNAs). One is specifically triggered by high-copy transgenes, and the other by feeding cells with double-stranded RNA (dsRNA)-producing bacteria. In this study, we designed a forward genetic screen for mutants deficient in dsRNA-induced silencing, and a powerful method to identify the relevant mutations by whole-genome sequencing. We present a set of 47 mutant alleles for five genes, revealing two previously unknown RNAi factors: a novel Paramecium-specific protein (Pds1) and a Cid1-like nucleotidyl transferase. Analyses of allelic diversity distinguish non-essential and essential genes and suggest that the screen is saturated for non-essential, single-copy genes. We show that non-essential genes are specifically involved in dsRNA-induced RNAi while essential ones are also involved in transgene-induced RNAi. One of the latter, the RNA-dependent RNA polymerase RDR2, is further shown to be required for all known types of siRNAs, as well as for sexual reproduction. These results open the way for the dissection of the genetic complexity, interconnection, mechanisms and natural functions of RNAi pathways in P. tetraurelia. PMID:24860163

  13. Functional Genomic Screening Reveals Core Modulators of Echinocandin Stress Responses in Candida albicans

    Directory of Open Access Journals (Sweden)

    Tavia Caplan

    2018-05-01

    Full Text Available Summary: Candida albicans is a leading cause of death due to fungal infection. Treatment of systemic candidiasis often relies on echinocandins, which disrupt cell wall synthesis. Resistance is readily acquired via mutations in the drug target gene, FKS1. Both basal tolerance and resistance to echinocandins require cellular stress responses. We performed a systematic analysis of 3,030 C. albicans mutants to define circuitry governing cellular responses to echinocandins. We identified 16 genes for which deletion or transcriptional repression enhanced echinocandin susceptibility, including components of the Pkc1-MAPK signaling cascade. We discovered that the molecular chaperone Hsp90 is required for the stability of Pkc1 and Bck1, establishing key mechanisms through which Hsp90 mediates echinocandin resistance. We also discovered that perturbation of the CCT chaperonin complex causes enhanced echinocandin sensitivity, altered cell wall architecture, and aberrant septin localization. Thus, we provide insights into the mechanisms by which cellular chaperones enable crucial responses to echinocandin-induced stress. : Caplan et al. screen 3,030 Candida albicans mutants to define circuitry governing cellular responses to echinocandins, the first-line therapy for systemic candidiasis. They reveal that the molecular chaperone Hsp90 is required for stability of Pkc1 and Bck1 and that the CCT chaperonin complex is a key modulator of echinocandin susceptibility. Keywords: fungal pathogen, Candida albicans, echinocandins, Hsp90, Pkc1, CCT complex, client protein, stress response, functional genomic screen, drug resistance

  14. Genetic Screen Reveals the Role of Purine Metabolism in Staphylococcus aureus Persistence to Rifampicin

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    Rebecca Yee

    2015-12-01

    Full Text Available Chronic infections with Staphylococcus aureus such as septicemia, osteomyelitis, endocarditis, and biofilm infections are difficult to treat because of persisters. Despite many efforts in understanding bacterial persistence, the mechanisms of persister formation in S. aureus remain elusive. Here, we performed a genome-wide screen of a transposon mutant library to study the molecular mechanisms involved in persistence of community-acquired S. aureus. Screening of the library for mutants defective in persistence or tolerance to rifampicin revealed many genes involved in metabolic pathways that are important for antibiotic persistence. In particular, the identified mutants belonged to metabolic pathways involved in carbohydrate, amino acid, lipid, vitamin and purine biosynthesis. Five mutants played a role in purine biosynthesis and two mutants, purB, an adenylosuccinate lyase, and purM, a phosphoribosylaminoimidazole synthetase, were selected for further confirmation. Mutants purB and purM showed defective persistence compared to the parental strain USA300 in multiple stress conditions including various antibiotics, low pH, and heat stress. The defect in persistence was restored by complementation with the wildtype purB and purM gene in the respective mutants. These findings provide new insights into the mechanisms of persistence in S. aureus and provide novel therapeutic targets for developing more effective treatment for persistent infections due to S. aureus.

  15. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency.

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    Ludmila Alekseeva

    Full Text Available Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.

  16. Hypoxia determines survival outcomes of bacterial infection through HIF-1α-dependent reprogramming of leukocyte metabolism

    OpenAIRE

    Thompson, A.A.R.; Dickinson, R.S.; Murphy, F.; Thomson, J.P.; Marriott, H.M.; Tavares, A.; Willson, J.; Williams, L.; Lewis, A.; Mirchandani, A.; Coelho, P.D.S.; Doherty, C.; Ryan, E.; Watts, E.; Morton, N.M.

    2017-01-01

    Hypoxia and bacterial infection frequently coexist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both Staphylococcus aureus and Streptococcus pneumoniae infections rapidly induced progressive neutrophil-mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning ...

  17. A genomewide screen for suppressors of Alu-mediated rearrangements reveals a role for PIF1.

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    Karen M Chisholm

    Full Text Available Alu-mediated rearrangement of tumor suppressor genes occurs frequently during carcinogenesis. In breast cancer, this mechanism contributes to loss of the wild-type BRCA1 allele in inherited disease and to loss of heterozygosity in sporadic cancer. To identify genes required for suppression of Alu-mediated recombination we performed a genomewide screen of a collection of 4672 yeast gene deletion mutants using a direct repeat recombination assay. The primary screen and subsequent analysis identified 12 candidate genes including TSA, ELG1, and RRM3, which are known to play a significant role in maintaining genomic stability. Genetic analysis of the corresponding human homologs was performed in sporadic breast tumors and in inherited BRCA1-associated carcinomas. Sequencing of these genes in high risk breast cancer families revealed a potential role for the helicase PIF1 in cancer predisposition. PIF1 variant L319P was identified in three breast cancer families; importantly, this variant, which is predicted to be functionally damaging, was not identified in a large series of controls nor has it been reported in either dbSNP or the 1000 Genomes Project. In Schizosaccharomyces pombe, Pfh1 is required to maintain both mitochondrial and nuclear genomic integrity. Functional studies in yeast of human PIF1 L319P revealed that this variant cannot complement the essential functions of Pfh1 in either the nucleus or mitochondria. Our results provide a global view of nonessential genes involved in suppressing Alu-mediated recombination and implicate variation in PIF1 in breast cancer predisposition.

  18. New radiosynthesis of 2-deoxy-2-[18F]fluoroacetamido-D-glucopyranose and its evaluation as a bacterial infections imaging agent

    International Nuclear Information System (INIS)

    Martinez, Miguel E.; Kiyono, Yasushi; Noriki, Sakon; Inai, Kunihiro; Mandap, Katheryn S.; Kobayashi, Masato; Mori, Tetsuya; Tokunaga, Yuji; Tiwari, Vijay N.; Okazawa, Hidehiko; Fujibayashi, Yasuhisa; Ido, Tatsuo

    2011-01-01

    Introduction: The diagnosis of infection and the ability to distinguish bacterial infection from nonbacterial inflammation by positron emission tomography (PET) have gained interest in recent years, but still few specific radiopharmaceuticals are available for use. In this study, we developed a new radiosynthesis method of 2-deoxy-2-[ 18 F]fluoroacetamido-D-glucopyranose ([ 18 F]FAG) by applying microwave irradiation and demonstrated that [ 18 F]FAG could be a potential radiopharmaceutical to distinguish bacterial infection from nonbacterial inflammation. Methods: 1,3,4,6-Tetra-O-acetyl-2-deoxy-2-bromoacetamido-D-glucopyranose was used as precursor, and labeling was performed under microwave irradiation conditions followed by alkaline hydrolysis and high-performance liquid chromatography (HPLC) purification. In vitro uptake of [ 18 F]FAG by Escherichia coli was performed. Tissue biodistribution of [ 18 F]FAG was performed in mice. Moreover, PET imaging acquisition of E. coli infection and nonbacterial inflammation models was performed in rats. Tissue radiotracer-accumulated sites were analyzed by hematoxylin and eosin staining and anti-E.coli immunostaining. Results: The radiosynthesis of [ 18 F]FAG was achieved with microwave irradiation, and the radiochemical yield was 9.7%±2.8% end of bombardment (EOB); the radiochemical purity was more than 98%, and the total synthesis time was 62 min. Compared with control group, in vitro uptake of [ 18 F]FAG by E. coli was significantly decrease in inhibition group (P 18 F]FAG from the animal body. [ 18 F]FAG clearly visualized the infection areas but not nonbacterial inflammation areas in PET studies. Quantitative analysis revealed that the uptake of [ 18 F]FAG into infection areas was significantly higher than that of [ 18 F]FAG into inflammation areas (P 18 F]FAG. Conclusions: Using 1,3,4,6-tetra-O-acetyl-2-deoxy-2-bromoacetamido-D-glucopyranose as a precursor, the new radiosynthesis method of [ 18 F]FAG was achieved in

  19. Serum sCD30: A promising biomarker for predicting the risk of bacterial infection after kidney transplantation.

    Science.gov (United States)

    Fernández-Ruiz, Mario; Parra, Patricia; López-Medrano, Francisco; Ruiz-Merlo, Tamara; González, Esther; Polanco, Natalia; Origüen, Julia; San Juan, Rafael; Andrés, Amado; Aguado, José María

    2017-04-01

    The transmembrane glycoprotein CD30 contributes to regulate the balance between Th 1 and Th 2 responses. Previous studies have reported conflicting results on the utility of its soluble form (sCD30) to predict post-transplant infection. Serum sCD30 was measured by a commercial ELISA assay at baseline and post-transplant months 1, 3, and 6 in 100 kidney transplant (KT) recipients (279 monitoring points). The impact of sCD30 levels on the incidence of overall, bacterial and opportunistic infection during the first 12 months after transplantation was assessed by Cox regression. There were no differences in serum sCD30 according to the occurrence of overall or opportunistic infection. However, sCD30 levels were higher in patients with bacterial infection compared to those without at baseline (P=.038) and months 1 (Ptransplantation (P=.006). Patients with baseline sCD30 levels ≥13.5 ng/mL had lower 12-month bacterial infection-free survival (35.0% vs 80.0%; PsCD30 levels ≥13.5 ng/mL remained as an independent risk factor for bacterial infection (adjusted hazard ratio [aHR]: 4.65; 95% confidence interval [CI]: 2.05-10.53; sCD30 levels ≥6.0 ng/mL at month 1 acted as a risk factor for subsequent bacterial infection (aHR: 5.29; 95% CI: 1.11-25.14; P=.036). Higher serum sCD30 levels were associated with an increased risk of bacterial infection after KT. We hypothesize that this biomarker reflects a Th 2 -polarized T-cell response, which exerts a detrimental effect on the immunity against bacterial pathogens. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Laboratory changes and levels of biomarkers in localized bacterial infections and sepsis in children

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    Larysa Pypa

    2017-08-01

    Full Text Available Background. The success of sepsis treatment depends on early diagnosis of the generalization of bacterial infection, but the nonspecificity of clinical manifestations often makes the diagnosis delayed. Therefore, the search for highly specific and sensitive biomarkers for early diagnosis of sepsis is relevant. The aim of our research is investigate the laboratory features and diagnostic value of a number of modern biomarkers for the diagnosis of sepsis in children. Materials and methods. of general laboratory studies and determination of CRP level were performed in 115 children with generalized and localized forms of bacterial infections. The main group (47 children - children with sepsis, a comparison group (68 children - with a localized bacterial infection of various localization. The age of children was from 1 month. up to 18 years. Grouping was performed according to the presence of signs and symptoms of SIRS and organ dysfunction. Determination of the level of procalcitonin and TNF-α was performed in 31 children of the main group, 45 children in the comparison group and 30 children in the control group (children without signs of inflammation. Prespepsin levels were determined in 16 main group children,14 in the comparison group and26 in the control group. Results. During the study, it was found that the level of leukocytosis was much higher and continued 2.6 times longer in the main group than in the children of the comparison group (p <0.01.Anemia was found in 76.6% of the children in the main group, while in the comparator group, the anemia syndrome was diagnosed 3.7 times less frequently. In the study of CRP in the main group, its level reached 44.7 mg / l and 28.3 mg / l in the comparison group, the specificity and sensitivity for diagnosis of sepsis was 46.8% and 51.5% respectively. The mean TNF-α level in children in the main group was 280.3 pg / ml CI 95% [243.9-316.7], which was 1.5 times higher than in children with a localized

  1. Bacterial infection identification by an anti-peptidoglycan aptamer labeled with Technetium-99m

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Antero Silva Ribeiro; Ferreira, Iêda Mendes [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Barros, Andre Luis Branco de; Cardoso, Valbert Nascimento [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Full text: Introduction: A variety of radiopharmaceuticals is used to detect infection, but long-term clinical use has shown that the majority of them cannot distinguish between inflammation and infection. Nuclear medicine clinics are still awaiting the optimal scintigraphic imaging agents capable of discriminating between infection and inflammation, and between fungal and bacterial infections. Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. Material and Methods: An aptamer for the peptidoglycan (main constituent of bacterial cell walls) termed Antibac1 was selected in a previous work. In the present study, this aptamer were labeled with {sup 99m}Tc and evaluated for bacterial infections identification by scintigraphy. All protocols were approved by the local Ethics Committee for Animal Experimentation of the Federal University of Minas Gerais (CETEA / UFMG), Protocol number 108/2014. Labeling with {sup 99m}Tc was performed by the direct method and the complex stability was evaluated in saline, plasma and presence of cysteine. The biodistribution and scintigraphic imaging studies with the {sup 99m}Tc-Antibac1 were carried out in two distinct experimental infection models: Swiss mice infected in the right thigh with Staphylococcus aureus or Candida albicans. {sup 99m}Tc radiolabeled library, consisting of oligonucleotides with random sequences, was used as a control in both experimental models. The direct radiolabeling allowed radiolabel yields above 90%. Results: A high complex stability was obtained in saline solution and plasma, but 51% of transchelation was verified after 24 h in the presence of cysteine. Scintigraphic images of S. aureus infected mice that received the {sup 99m}Tc-Antibac1 showed target to non-target ratios of 4.7 ± 0.90 and 4.6 ± 0.10 at 1.5 and 3.0 h, respectively. These values were statistically higher than

  2. Optimization of serious bacterial infections intensive therapy in children in Anesthesiology and Intensive Care Department

    Directory of Open Access Journals (Sweden)

    M. Yu. Kurochkin

    2014-08-01

    Full Text Available Effective selection of antibiotics in children with severe bacterial infections is often difficult because of microflora resistance. Extracorporeal detoxication methods, particularly discrete plasmapheresis are usually used for septic shock and total organ failure prevention. The aim of research. To conduct microbiological monitoring and to study a dynamics of medium molecular peptides in discrete plasmapheresis for intensive care optimization in children with severe bacterial infections in Anesthesiology and Intensive Care Department (AICU. Materials and methods. We investigated respiratory tract microflora by bacteriological method in 120 newborns and 30 children from 1 month with severe bacterial infections at admission and during prolonged stay in AICU. Discrete plasmapheresis was held in four children. Dynamic of medium molecular peptides was studied at admission, before discrete plasmapheresis and after it. Statistical data processing was performed using the Microsoft Excel software package. Results. It was found that in AICU in older children in admission grampositive and gramnegative flora was defined in equal quantity. The best sensitivity of the respiratory tract microflora was for the glycopeptides, oxazolidinones , II generation cephalosporins and macrolides, more than 60% - for aminoglycosides and lincosamides. However, when children spent more than 7-14 days in the department, nosocomial microflora was represented primarily by gram-negative organisms (80%, especially Pseudomonas aeruginosa. It was found to be inappropriate to use cephalosporins and macrolides in AICU for older children after their long stay there; the sensitivity to aminoglycosides was less than 60%, to anti-pseudomonal carbapenems not more than 30%. In AICU of newborns grampositive flora was found in 95%, mostly Staphylococcus haemolyticus. It was entirely sensitive for glycopeptides, oxazolidinones, fluoroquinolones, carbapenems, and also for co-trimoxazole and

  3. Antibiotic prophylaxis for bacterial infections in afebrile neutropenic patients following chemotherapy.

    Science.gov (United States)

    Gafter-Gvili, Anat; Fraser, Abigail; Paul, Mical; Vidal, Liat; Lawrie, Theresa A; van de Wetering, Marianne D; Kremer, Leontien C M; Leibovici, Leonard

    2012-01-18

    Bacterial infections are a major cause of morbidity and mortality in patients who are neutropenic following chemotherapy for malignancy. Trials have shown the efficacy of antibiotic prophylaxis in reducing the incidence of bacterial infections but not in reducing mortality rates. Our systematic review from 2006 also showed a reduction in mortality. This updated review aimed to evaluate whether there is still a benefit of reduction in mortality when compared to placebo or no intervention. We searched the Cochrane Cancer Network Register of Trials (2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2011), MEDLINE (1966 to March 2011), EMBASE (1980 to March 2011), abstracts of conference proceedings and the references of identified studies. Randomised controlled trials (RCTs) or quasi-RCTs comparing different types of antibiotic prophylaxis with placebo or no intervention, or another antibiotic, to prevent bacterial infections in afebrile neutropenic patients. Two authors independently appraised the quality of each trial and extracted data from the included trials. Analyses were performed using RevMan 5.1 software. One-hundred and nine trials (involving 13,579 patients) that were conducted between the years 1973 to 2010 met the inclusion criteria. When compared with placebo or no intervention, antibiotic prophylaxis significantly reduced the risk of death from all causes (46 trials, 5635 participants; risk ratio (RR) 0.66, 95% CI 0.55 to 0.79) and the risk of infection-related death (43 trials, 5777 participants; RR 0.61, 95% CI 0.48 to 0.77). The estimated number needed to treat (NNT) to prevent one death was 34 (all-cause mortality) and 48 (infection-related mortality).Prophylaxis also significantly reduced the occurrence of fever (54 trials, 6658 participants; RR 0.80, 95% CI 0.74 to 0.87), clinically documented infection (48 trials, 5758 participants; RR 0.65, 95% CI 0.56 to 0.76), microbiologically documented infection

  4. Antibiotic prophylaxis for bacterial infections in afebrile neutropenic patients following chemotherapy

    Science.gov (United States)

    Gafter-Gvili, Anat; Fraser, Abigail; Paul, Mical; Vidal, Liat; Lawrie, Theresa A; van de Wetering, Marianne D; Kremer, Leontien CM; Leibovici, Leonard

    2014-01-01

    Background Bacterial infections are a major cause of morbidity and mortality in patients who are neutropenic following chemotherapy for malignancy. Trials have shown the efficacy of antibiotic prophylaxis in reducing the incidence of bacterial infections but not in reducing mortality rates. Our systematic review from 2006 also showed a reduction in mortality. Objectives This updated review aimed to evaluate whether there is still a benefit of reduction in mortality when compared to placebo or no intervention. Search methods We searched the Cochrane Cancer Network Register of Trials (2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2011), MEDLINE (1966 to March 2011), EMBASE (1980 to March 2011), abstracts of conference proceedings and the references of identified studies. Selection criteria Randomised controlled trials (RCTs) or quasi-RCTs comparing different types of antibiotic prophylaxis with placebo or no intervention, or another antibiotic, to prevent bacterial infections in afebrile neutropenic patients. Data collection and analysis Two authors independently appraised the quality of each trial and extracted data from the included trials. Analyses were performed using RevMan 5.1 software. Main results One-hundred and nine trials (involving 13,579 patients) that were conducted between the years 1973 to 2010 met the inclusion criteria. When compared with placebo or no intervention, antibiotic prophylaxis significantly reduced the risk of death from all causes (46 trials, 5635 participants; risk ratio (RR) 0.66, 95% CI 0.55 to 0.79) and the risk of infection-related death (43 trials, 5777 participants; RR 0.61, 95% CI 0.48 to 0.77). The estimated number needed to treat (NNT) to prevent one death was 34 (all-cause mortality) and 48 (infection-related mortality). Prophylaxis also significantly reduced the occurrence of fever (54 trials, 6658 participants; RR 0.80, 95% CI 0.74 to 0.87), clinically documented infection

  5. Bacterial infection identification by an anti-peptidoglycan aptamer labeled with Technetium-99m

    International Nuclear Information System (INIS)

    Andrade, Antero Silva Ribeiro; Ferreira, Iêda Mendes; Barros, Andre Luis Branco de; Cardoso, Valbert Nascimento

    2017-01-01

    Full text: Introduction: A variety of radiopharmaceuticals is used to detect infection, but long-term clinical use has shown that the majority of them cannot distinguish between inflammation and infection. Nuclear medicine clinics are still awaiting the optimal scintigraphic imaging agents capable of discriminating between infection and inflammation, and between fungal and bacterial infections. Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. Material and Methods: An aptamer for the peptidoglycan (main constituent of bacterial cell walls) termed Antibac1 was selected in a previous work. In the present study, this aptamer were labeled with 99m Tc and evaluated for bacterial infections identification by scintigraphy. All protocols were approved by the local Ethics Committee for Animal Experimentation of the Federal University of Minas Gerais (CETEA / UFMG), Protocol number 108/2014. Labeling with 99m Tc was performed by the direct method and the complex stability was evaluated in saline, plasma and presence of cysteine. The biodistribution and scintigraphic imaging studies with the 99m Tc-Antibac1 were carried out in two distinct experimental infection models: Swiss mice infected in the right thigh with Staphylococcus aureus or Candida albicans. 99m Tc radiolabeled library, consisting of oligonucleotides with random sequences, was used as a control in both experimental models. The direct radiolabeling allowed radiolabel yields above 90%. Results: A high complex stability was obtained in saline solution and plasma, but 51% of transchelation was verified after 24 h in the presence of cysteine. Scintigraphic images of S. aureus infected mice that received the 99m Tc-Antibac1 showed target to non-target ratios of 4.7 ± 0.90 and 4.6 ± 0.10 at 1.5 and 3.0 h, respectively. These values were statistically higher than found for the 99m Tc

  6. Effects of the wood extractive betulinol and 17beta-oestradiol on reproduction in zebrafish, Danio rerio (Hamilton)--complications due to a bacterial infection.

    Science.gov (United States)

    Christianson-Heiska, I; Wahteristo, P; Kastilan, E-L; Bergelin, E; Bylund, G; Isomaa, B

    2004-05-01

    Zebrafish were exposed to the wood extractive betulinol (5 microg L(-1)) and to 17beta-oestradiol (E2, 0.27 microg L(-1)) for 8 weeks in an attempt to study the possible endocrine-disrupting activity of betulinol. Females exposed to betulinol showed increased spawning intensity, while males exposed to betulinol and E2 had increased incidences of structural alterations in the testes. However, histological examination of the fish revealed that they were infected by acid-fast bacteria suspected to be Mycobacterium sp. despite a careful examination of their health state prior to the onset of the experiment. Fish exposed to betulinol and E2 showed more serious consequences of the bacterial infection than control fish indicating that the test chemicals had weakened the immune defence of the fish. When the exposure was repeated with healthy fish, an increase in the proportion of spermatogonia was seen in the testes of betulinol-treated males. A similar alteration, although not statistically significant, was also seen in the first experiment. However, no increase in the incidences of structural alterations in the testes was seen in betulinol- and E2-treated fish in the second experiment. Our study indicates that betulinol might have an endocrine-disrupting effect in zebrafish, but the increase in incidences of structural alterations in the testes might have been caused by a synergistic action between the test compounds and the bacterial infection. Our study stresses the importance of carefully checking the health of experimental fish, not only prior to the onset of an experiment but also upon termination of the experiment, in order to avoid misinterpretation of the results.

  7. Perinatal Exposure to Environmental Tobacco Smoke (ETS Enhances Susceptibility to Viral and Secondary Bacterial Infections

    Directory of Open Access Journals (Sweden)

    Jocelyn A. Claude

    2012-10-01

    Full Text Available Studies suggest childhood exposure to environmental tobacco smoke (ETS leads to increased incidence of infections of the lower respiratory tract. The objective of this study was to determine whether perinatal exposure to ETS increases the incidence, morbidity and severity of respiratory influenza infection and whether a secondary bacterial challenge at the peak of a pre-existing viral infection creates an enhanced host-pathogen susceptibility to an opportunistic infection. Timed-pregnant female Balb/c mice were exposed to either ETS for 6 h/day, 7 d/week beginning on gestation day 14 and continuing with the neonates to 6 weeks of age. Control animals were exposed to filtered air (FA. At the end of exposure, mice were intranasally inoculated with a murine-adapted influenza A. One week later, an intranasal inoculation of S. aureus bacteria was administered. The respective treatment groups were: bacteria only, virus only or virus+bacteria for both FA and ETS-exposed animals for a total of six treatment groups. Animal behavior and body weights were documented daily following infection. Mice were necropsied 1-day post-bacterial infection. Bronchoalveolar lavage fluid (BALF cell analysis demonstrated perinatal exposure to ETS, compared to FA, leads to delayed but enhanced clinical symptoms and enhanced total cell influx into the lungs associated with viral infection followed by bacterial challenge. Viral infection significantly increases the number of neutrophils entering the lungs following bacterial challenge with either FA or ETS exposure, while the influx of lymphocytes and monocytes is significantly enhanced only by perinatal ETS exposure. There is a significant increase in peribronchiolar inflammation following viral infection in pups exposed to ETS compared with pups exposed to FA, but no change is noted in the degree of lung injury between FA and ETS-exposed animals following bacterial challenge. The data suggests perinatal exposure to ETS

  8. Selection of aptamers for use as radiopharmaceuticals in bacterial infection diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ieda Mendes; Faria, Ligia Santana de; Correa, Cristiane Rodrigues; Andrade, Antero Silva Ribeiro de, E-mail: imendesf@yahoo.com.br, E-mail: antero@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    The difficulty in early detection of specific foci in the bacterial infection caused by bacteria has raised the need to search for new techniques for this purpose, since these foci require prolonged treatment with antibiotics and in some cases even drainage or, if applicable, removal of prostheses or grafts. Detection of bacterial infections by scintigraphy has the advantage that an image of the whole body could be obtained. This study aims to obtain aptamers specific bacteria for future use as radiopharmaceutical. The SELEX (Systematic Evolution of Ligands by Exponential Enrichment) methodology can generate oligonucleotides (aptamers) that are able to bind with high affinity and specificity to a specific target, from small molecules to complex proteins, by using rounds of enrichment and amplification. Aptamers can be labeled with different radionucleotides such as {sup 99m}Tc, {sup 18}F and {sup 32}P. In this study aptamers anti-peptidoglycan, the main component of the outer cell wall of bacteria, were obtained through SELEX. The SELEX started with a pool of ssDNA that had 10{sup 15}different sequences (library), each oligo has two fixed regions merging a portion of 25 random nucleotides. Initially, the library of ssDNA was incubated with peptidoglycan, for 1h at 37 dec C with stirring. Subsequently, amplification of oligonucleotides that were able to bind to peptidoglycan was performed by PCR (Polymerase Chain Reaction). The amplified oligonucleotides were again incubated with peptidoglycan, amplified and purified. At the end of 15 rounds of selection the oligonucleotides were cloned using TOPO plasmid and Escherichia coli strain Top10F'. The plasmid DNA from 40 colonies were extracted and quantified. The plasmids were sequenced using the sequencing MegaBase, and two different aptamers sequences were obtained from all clones. The aptamers obtained were synthesized and subsequently labeled with {sup 32}P in the 5' end. The labeled aptamers were incubated

  9. Selection of aptamers for use as radiopharmaceuticals in bacterial infection diagnosis

    International Nuclear Information System (INIS)

    Ferreira, Ieda Mendes; Faria, Ligia Santana de; Correa, Cristiane Rodrigues; Andrade, Antero Silva Ribeiro de

    2013-01-01

    The difficulty in early detection of specific foci in the bacterial infection caused by bacteria has raised the need to search for new techniques for this purpose, since these foci require prolonged treatment with antibiotics and in some cases even drainage or, if applicable, removal of prostheses or grafts. Detection of bacterial infections by scintigraphy has the advantage that an image of the whole body could be obtained. This study aims to obtain aptamers specific bacteria for future use as radiopharmaceutical. The SELEX (Systematic Evolution of Ligands by Exponential Enrichment) methodology can generate oligonucleotides (aptamers) that are able to bind with high affinity and specificity to a specific target, from small molecules to complex proteins, by using rounds of enrichment and amplification. Aptamers can be labeled with different radionucleotides such as 99m Tc, 18 F and 32 P. In this study aptamers anti-peptidoglycan, the main component of the outer cell wall of bacteria, were obtained through SELEX. The SELEX started with a pool of ssDNA that had 10 15 different sequences (library), each oligo has two fixed regions merging a portion of 25 random nucleotides. Initially, the library of ssDNA was incubated with peptidoglycan, for 1h at 37 dec C with stirring. Subsequently, amplification of oligonucleotides that were able to bind to peptidoglycan was performed by PCR (Polymerase Chain Reaction). The amplified oligonucleotides were again incubated with peptidoglycan, amplified and purified. At the end of 15 rounds of selection the oligonucleotides were cloned using TOPO plasmid and Escherichia coli strain Top10F'. The plasmid DNA from 40 colonies were extracted and quantified. The plasmids were sequenced using the sequencing MegaBase, and two different aptamers sequences were obtained from all clones. The aptamers obtained were synthesized and subsequently labeled with 32 P in the 5' end. The labeled aptamers were incubated with 10 7 Staphylococcus aureus

  10. Elaborate cellulosome architecture of Acetivibrio cellulolyticus revealed by selective screening of cohesin–dockerin interactions

    Directory of Open Access Journals (Sweden)

    Yuval Hamberg

    2014-10-01

    cellulosome’s total cohesin and dockerin sequence diversity, emphasizing the testing of unusual and previously-unknown protein modules. The screen revealed several novel cell-bound cellulosome architectures, thus expanding on those previously known, as well as soluble cellulose systems that are not bound to the bacterial cell surface. This study sets the stage for screening the entire complement of cellulosomal components from A. cellulolyticus and other organisms with large cellulosome systems. The knowledge gained by such efforts brings us closer to understanding the exceptional catalytic abilities of cellulosomes and will allow the use of novel cellulosomal components in artificial assemblies and in enzyme cocktails for sustainable energy-related research programs.

  11. [Pharmacokinetic and clinical experience with flomoxef in bacterial infection in children].

    Science.gov (United States)

    Hosoda, T; Ichioka, T; Miyao, M

    1987-08-01

    Pharmacokinetic and clinical studies were performed on flomoxef (FMOX, 6315-S), a new oxacephem antibiotic, as follows. 1. Pharmacokinetics Serum concentrations of FMOX were measured in 2 cases given 20 mg/kg bolus injection. In the 2 cases, peak concentrations of the drug were 44.3 and 197 micrograms/ml at 15 minutes, T1/2 (beta) were 0.76 and 0.47 hour and AUC were 44.8 and 169.5 micrograms.hr/ml, respectively. Urinary recovery rates for these cases during 6 hours were 83.1 and 54.9%, respectively. The extremely high peak serum concentration in one case may be attributed to dehydration. 2. Clinical efficacy FMOX was administrated intravenously to 12 patients, 6 with pneumonia, 2 with cellulitis, 1 each with bronchitis, tonsillitis, purulent lymphadenitis and subcutaneous abscess, in doses of 55.0-120.0 mg/kg (average 82.2 mg/kg) t.i.d. for 4-13 days (average 6.2 days). The overall efficacy rate was 100%, with excellent responses in 10 and good in 2. Bacteriological efficacy was excellent; 4 of 5 strains were eradicated and 1 strain was decreased. No clinical side effect was observed. Laboratory abnormality was observed in 1 case with transient eosinophilia. The above results suggested that FMOX would be an useful antibiotic for treating pediatric bacterial infections.

  12. Dietary Selenium in Adjuvant Therapy of Viral and Bacterial Infections12

    Science.gov (United States)

    Steinbrenner, Holger; Al-Quraishy, Saleh; Dkhil, Mohamed A; Wunderlich, Frank; Sies, Helmut

    2015-01-01

    Viral and bacterial infections are often associated with deficiencies in macronutrients and micronutrients, including the essential trace element selenium. In selenium deficiency, benign strains of Coxsackie and influenza viruses can mutate to highly pathogenic strains. Dietary supplementation to provide adequate or supranutritional selenium supply has been proposed to confer health benefits for patients suffering from some viral diseases, most notably with respect to HIV and influenza A virus (IAV) infections. In addition, selenium-containing multimicronutrient supplements improved several clinical and lifestyle variables in patients coinfected with HIV and Mycobacterium tuberculosis. Selenium status may affect the function of cells of both adaptive and innate immunity. Supranutritional selenium promotes proliferation and favors differentiation of naive CD4-positive T lymphocytes toward T helper 1 cells, thus supporting the acute cellular immune response, whereas excessive activation of the immune system and ensuing host tissue damage are counteracted through directing macrophages toward the M2 phenotype. This review provides an up-to-date overview on selenium in infectious diseases caused by viruses (e.g., HIV, IAV, hepatitis C virus, poliovirus, West Nile virus) and bacteria (e.g., M. tuberculosis, Helicobacter pylori). Data from epidemiologic studies and intervention trials, with selenium alone or in combination with other micronutrients, and animal experiments are discussed against the background of dietary selenium requirements to alter immune functions. PMID:25593145

  13. The role of T cell subsets and cytokines in the regulation of intracellular bacterial infection

    Directory of Open Access Journals (Sweden)

    Oliveira S.C.

    1998-01-01

    Full Text Available Cellular immune responses are a critical part of the host's defense against intracellular bacterial infections. Immunity to Brucella abortus crucially depends on antigen-specific T cell-mediated activation of macrophages, which are the major effectors of cell-mediated killing of this organism. T lymphocytes that proliferate in response to B. abortus were characterized for phenotype and cytokine activity. Human, murine, and bovine T lymphocytes exhibited a type 1 cytokine profile, suggesting an analogous immune response in these different hosts. In vivo protection afforded by a particular cell type is dependent on the antigen presented and the mechanism of antigen presentation. Studies using MHC class I and class II knockout mice infected with B. abortus have demonstrated that protective immunity to brucellosis is especially dependent on CD8+ T cells. To target MHC class I presentation we transfected ex vivo a murine macrophage cell line with B. abortus genes and adoptively transferred them to BALB/c mice. These transgenic macrophage clones induced partial protection in mice against experimental brucellosis. Knowing the cells required for protection, vaccines can be designed to activate the protective T cell subset. Lastly, as a new strategy for priming a specific class I-restricted T cell response in vivo, we used genetic immunization by particle bombardment-mediated gene transfer

  14. Cockroaches ’ bacterial infections in wards of hospitals, Hamedan city, west of Iran

    Directory of Open Access Journals (Sweden)

    Nejati Jalil

    2012-10-01

    Full Text Available Objective: To identify the relationship between different species of cockroaches with their bacterial infection in different wards of Hamedan county hospitals, western Iran. Methods: Using sticky trap, hand collection and glass trap, 250 cockroaches were collected from 14 wards of 5 hospitals. After having their identification determined by detection key, all of them were used to isolate bacteria from cuticle and alimentary tract. Results: From four identified species, Blatella germanica were the most common in all of the wards (88.8% and next was the Periplaneta Americana (8%. 20 bacteria species isolated from cockroaches' surface and 21 from digestive organ. Escherichia coli were the most predominant bacteria isolated from external surface (26.5 % as well as alimentary tract (30.8%. The frequency of investigated bacteria on cockroaches' body surface was not significantly different between Periplaneta Americana and Blattella germanica except for Kllebsiella oxytoca (P<0.001 and Providensia Spp (P=0.035. Also, frequency of detected bacteria in cockroaches' digestive organ was not significantly different between these two species. Furthermore, the frequency of bacteria isolated from the cockroaches' external surface was not significantly different from that of digestive organ except for shigella disantery (P<0.001, Pseudomonas aeroginosa (P<0.001 and Klebsiella oxytoca (P=0.01 3. Conclusions: Since cockroaches can carry pathogenic bacteria, so their existence in the hospitals could be a serious public health problem. It is suggested to compile programs in order to control cockroaches especially in the hospitals.

  15. Optimized localization of bacterial infections with technetium-99m labelled human immunoglobulin after protein charge selection

    International Nuclear Information System (INIS)

    Welling, M.; Feitsma, H.I.J.; Calame, W.; Ensing, G.J.; Goedemans, W.; Pauwels, E.K.J.

    1994-01-01

    To improve the scintigraphic detection of bacterial infections a protein charge-purified fraction of polyclonal human immunoglobulin was applied as a radiopharmaceutical. This purification was achieved by attaching the immunoglobulin to an anion-exchanger column and by obtaining the column-bound fraction with buffer. The binding to bacteria in vitro and the target to non-target ratios of an experimental thigh infection with Staphylococcus aureus or Klebsiella pneumoniae in mice were evaluated to compare the purified and the unpurified immunoglobulin. The percentage of binding to all gram-positive and gram-negative bacteria used in this study was significantly (P 99m Tc-labelled protein charge-purified polyclonal human immunoglobulin was administered intravenously. At all time intervals the target (infected thighs) to non-target (non-infected thighs) ratios for both infections were significantly higher (P 99m Tc-labelled protein charge-purified immunoglobulin localizes both a gram-positive and a gram-negative thigh infection more intensely and faster than 99m Tc-labelled unpurified immunoglobulin. (orig.)

  16. Clinical evaluation of technetium-99m infecton for the localisation of bacterial infection

    International Nuclear Information System (INIS)

    Britton, K.E.; Vinjamuri, S.; Hall, A.V.; Solanki, K.; Siraj, Q.H.; Bomanji, J.; Das, S.

    1997-01-01

    The aim of the study was to distinguish infection from inflammation in patients with suspected infection using technetium-99m Infecton. Ninety-nine patients (102 studies) referred for infection evaluation underwent imaging with 400 MBq 99m Tc-Infecton at 1 and 4 h. Most patients had appropriate microbiological tests and about half (56) had radiolabelled white cell scans as well. No adverse effects were noted in any patient. The clinical efficacy of 99m Tc-Infecton depended in part on whether imaging was undertaken during antibiotic therapy for infection or not. In consultation with the microbiologist, 5-14 days of appropriate and successful antibiotic therapy was considered adequate to classify some results as true-negatives. The figures for sensitivity and specificity of 99m Tc-Infecton for active or unsuccessfully treated infection were 83% and 91% respectively. It is concluded that 99m Tc-Infecton imaging contributed to the differential diagnosis of inflammation. It is being used as the first imaging modality when bacterial infection is suspected. (orig.). With 2 figs., 1 tab

  17. Reptiles as Reservoirs of Bacterial Infections: Real Threat or Methodological Bias?

    Science.gov (United States)

    Zancolli, Giulia; Mahsberg, Dieter; Sickel, Wiebke; Keller, Alexander

    2015-10-01

    Bacterial infections secondary to snakebites and human pathogens (e.g., Salmonella) have been linked to the oral microbiota of snakes and pet reptiles. Based on culture-dependent studies, it is speculated that snakes' oral microbiota reflects the fecal flora of their ingested preys. However, cultured-based techniques have been shown to be limited as they fail to identify unculturable microorganisms which represent the vast majority of the microbial diversity. Here, we used culture-independent high-throughput sequencing to identify reptile-associated pathogens and to characterize the oral microbial community of five snakes, one gecko, and two terrapins. Few potential human pathogens were detected at extremely low frequencies. Moreover, bacterial taxa represented in the snake's oral cavity bore little resemblance to their preys' fecal microbiota. Overall, we found distinct, highly diverse microbial communities with consistent, species-specific patterns contrary to previous culture-based studies. Our study does not support the widely held assumption that reptiles' oral cavity acts as pathogen reservoir and provides important insights for future research.

  18. Prevalence of Selected Bacterial Infections Associated with the Use of Animal Waste in Louisiana

    Directory of Open Access Journals (Sweden)

    Paul B. Tchounwou

    2005-04-01

    Full Text Available Human health is a major concern when considering the disposal of large quantities of animal waste. Health concerns could arise from exposure to pathogens and excess nitrogen associated with this form of pollution. The objective was to collect and analyze health data related to selected bacterial infections associated with the use of animal waste in Louisiana. An analysis of adverse health effects has been conducted based on the incidence/prevalence rates of campylobacteriosis, E. coli O157:H7 infection, salmonellosis and shigellosis. The number of reported cases increased during the summer months. Analysis of health data showed that reported disease cases of E. coli O157:H7 were highest among Caucasian infants in the 0-4 year old age category and in Caucasian children in the 5-9 year old age category. Fatalities resulting from salmonellosis are low and increases sharply with age. The number of reported cases of shigellosis was found to be higher in African American males and females than in Caucasians. The high rate of identification in the younger population may result from the prompt seeking of medical care, as well as the frequent ordering of stool examination when symptoms become evident among this group of the population. The association with increasing age and fatality due to salmonellosis could be attributed to declining health and weaker immune systems often found in the older population. It is concluded that both animal waste and non-point source pollution may have a significant impact on human health.

  19. Dynamic network reconstruction from gene expression data applied to immune response during bacterial infection.

    Science.gov (United States)

    Guthke, Reinhard; Möller, Ulrich; Hoffmann, Martin; Thies, Frank; Töpfer, Susanne

    2005-04-15

    The immune response to bacterial infection represents a complex network of dynamic gene and protein interactions. We present an optimized reverse engineering strategy aimed at a reconstruction of this kind of interaction networks. The proposed approach is based on both microarray data and available biological knowledge. The main kinetics of the immune response were identified by fuzzy clustering of gene expression profiles (time series). The number of clusters was optimized using various evaluation criteria. For each cluster a representative gene with a high fuzzy-membership was chosen in accordance with available physiological knowledge. Then hypothetical network structures were identified by seeking systems of ordinary differential equations, whose simulated kinetics could fit the gene expression profiles of the cluster-representative genes. For the construction of hypothetical network structures singular value decomposition (SVD) based methods and a newly introduced heuristic Network Generation Method here were compared. It turned out that the proposed novel method could find sparser networks and gave better fits to the experimental data. Reinhard.Guthke@hki-jena.de.

  20. Study of Bacterial Infections Among Patients Receiving Kidney Transplant in Mashhad, Iran.

    Science.gov (United States)

    Mansury, Davood; Khaledi, Azad; Ghazvini, Kiarash; Sabbagh, Mahin Ghorban; Zare, Hosna; Rokni-Hosseini, Mohammad Hossein; Vazini, Hossein

    2017-11-15

    Over the past 2 decades, significant advances have been made in the management of infections after transplant; however, transplant recipients are still at high risk of infectious complications. This study aimed to evaluate the prevalence of bacterial infections and antimicrobial resistance patterns in kidney transplant recipients. This cross-sectional study included 356 patients who received kidney transplants, regardless of the underlying disease, from 2013 to 2015 at the Montaserieh Transplant Hospital (Mashhad, Iran). Clinical samples collected from patients were sent to the microbiology laboratory for culture processing. Typing of bacteria was conducted, and susceptibility testing was performed according to the Clinical and Laboratory Standards Institute guideline by use the of disk diffusion agar method. Data were then analyzed by SPSS software (SPSS: An IBM Company, IBM Corporation, Armonk, NY, USA) using chi-square test. Among 356 kidney recipients (206 men and 150 women), 115 (32.3%) received transplants from living donors and 241 (67.7%) received transplants from deceased donors. Of 356 total patients, 112 patients (31.5%) had an infection at various times after transplant. The most common gram-negative and gram-positive isolated bacteria were Escherichia coli and coagulase-negative Staphylococcus, with prevalence rates of 66.1% and 48.6%. Most of the isolates were resistant against selected antibiotics. Because of the high prevalence of infection among transplant patients, infection prevention should receive more attention, and antibiotic susceptibility should be determined before treatment.

  1. Powerful colloidal silver nanoparticles for the prevention of gastrointestinal bacterial infections

    International Nuclear Information System (INIS)

    Le, Anh-Tuan; Le, Thi Tam; Nguyen, Van Quy; Tran, Huy Hoang; Dang, Duc Anh; Tran, Quang Huy; Vu, Dinh Lam

    2012-01-01

    In this work we have demonstrated a powerful disinfectant ability of colloidal silver nanoparticles (NPs) for the prevention of gastrointestinal bacterial infections. The silver NPs colloid was synthesized by a UV-enhanced chemical precipitation. Two gastrointestinal bacterial strains of Escherichia coli (ATCC 43888-O157:k-:H7) and Vibrio cholerae (O1) were used to verify the antibacterial activity of the as-prepared silver NPs colloid by means of surface disinfection assay in agar plates and turbidity assay in liquid media. Transmission electron microscopy was also employed to analyze the ultrastructural changes of bacterial cells caused by silver NPs. Noticeably, our silver NPs colloid displayed a highly effective bactericidal effect against two tested gastrointestinal bacterial strains at a silver concentration as low as ∼3 mg l −1 . More importantly, the silver NPs colloid showed an enhancement of antibacterial activity and long-lasting disinfectant effect as compared to conventional chloramin B (5%) disinfection agent. These advantages of the as-prepared colloidal silver NPs make them very promising for environmental treatments contaminated with gastrointestinal bacteria and other infectious pathogens. Moreover, the powerful disinfectant activity of silver-containing materials can also help in controlling and preventing further outbreak of diseases. (paper)

  2. Antimicrobial Resistance in Invasive Bacterial Infections in Hospitalized Children, Cambodia, 2007-2016.

    Science.gov (United States)

    Fox-Lewis, Andrew; Takata, Junko; Miliya, Thyl; Lubell, Yoel; Soeng, Sona; Sar, Poda; Rith, Kolthida; McKellar, Gregor; Wuthiekanun, Vanaporn; McGonagle, Erin; Stoesser, Nicole; Moore, Catrin E; Parry, Christopher M; Turner, Claudia; Day, Nicholas P J; Cooper, Ben S; Turner, Paul

    2018-05-01

    To determine trends, mortality rates, and costs of antimicrobial resistance in invasive bacterial infections in hospitalized children, we analyzed data from Angkor Hospital for Children, Siem Reap, Cambodia, for 2007-2016. A total of 39,050 cultures yielded 1,341 target pathogens. Resistance rates were high; 82% each of Escherichia coli and Klebsiella pneumoniae isolates were multidrug resistant. Hospital-acquired isolates were more often resistant than community-acquired isolates; resistance trends over time were heterogeneous. K. pneumoniae isolates from neonates were more likely than those from nonneonates to be resistant to ampicillin-gentamicin and third-generation cephalosporins. In patients with community-acquired gram-negative bacteremia, third-generation cephalosporin resistance was associated with increased mortality rates, increased intensive care unit admissions, and 2.26-fold increased healthcare costs among survivors. High antimicrobial resistance in this setting is a threat to human life and the economy. In similar low-resource settings, our methods could be reproduced as a robust surveillance model for antimicrobial resistance.

  3. Synergistic antibacterial effect of silver and ebselen against multidrug-resistant Gram-negative bacterial infections.

    Science.gov (United States)

    Zou, Lili; Lu, Jun; Wang, Jun; Ren, Xiaoyuan; Zhang, Lanlan; Gao, Yu; Rottenberg, Martin E; Holmgren, Arne

    2017-08-01

    Multidrug-resistant (MDR) Gram-negative bacteria account for a majority of fatal infections, and development of new antibiotic principles and drugs is therefore of outstanding importance. Here, we report that five most clinically difficult-to-treat MDR Gram-negative bacteria are highly sensitive to a synergistic combination of silver and ebselen. In contrast, silver has no synergistic toxicity with ebselen on mammalian cells. The silver and ebselen combination causes a rapid depletion of glutathione and inhibition of the thioredoxin system in bacteria. Silver ions were identified as strong inhibitors of Escherichia coli thioredoxin and thioredoxin reductase, which are required for ribonucleotide reductase and DNA synthesis and defense against oxidative stress. The bactericidal efficacy of silver and ebselen was further verified in the treatment of mild and acute MDR E. coli peritonitis in mice. These results demonstrate that thiol-dependent redox systems in bacteria can be targeted in the design of new antibacterial drugs. The silver and ebselen combination offers a proof of concept in targeting essential bacterial systems and might be developed for novel efficient treatments against MDR Gram-negative bacterial infections. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  4. Screens

    OpenAIRE

    2016-01-01

    This Sixth volume in the series The Key Debates. Mutations and Appropriations in European Film Studies investigates the question of screens in the context both of the dematerialization due to digitalization and the multiplication of media screens. Scholars offer various infomations and theories of topics such as the archeology of screen, film and media theories, contemporary art, pragmatics of new ways of screening (from home video to street screening).

  5. Zebrafish chemical screening reveals the impairment of dopaminergic neuronal survival by cardiac glycosides.

    Directory of Open Access Journals (Sweden)

    Yaping Sun

    Full Text Available Parkinson's disease is a neurodegenerative disorder characterized by the prominent degeneration of dopaminergic (DA neurons among other cell types. Here we report a first chemical screen of over 5,000 compounds in zebrafish, aimed at identifying small molecule modulators of DA neuron development or survival. We find that Neriifolin, a member of the cardiac glycoside family of compounds, impairs survival but not differentiation of both zebrafish and mammalian DA neurons. Cardiac glycosides are inhibitors of Na(+/K(+ ATPase activity and widely used for treating heart disorders. Our data suggest that Neriifolin impairs DA neuronal survival by targeting the neuronal enriched Na(+/K(+ ATPase α3 subunit (ATP1A3. Modulation of ionic homeostasis, knockdown of p53, or treatment with antioxidants protects DA neurons from Neriifolin-induced death. These results reveal a previously unknown effect of cardiac glycosides on DA neuronal survival and suggest that it is mediated through ATP1A3 inhibition, oxidative stress, and p53. They also elucidate potential approaches for counteracting the neurotoxicity of this valuable class of medications.

  6. In vivo RNAi screen reveals neddylation genes as novel regulators of Hedgehog signaling.

    Directory of Open Access Journals (Sweden)

    Juan Du

    Full Text Available Hedgehog (Hh signaling is highly conserved in all metazoan animals and plays critical roles in many developmental processes. Dysregulation of the Hh signaling cascade has been implicated in many diseases, including cancer. Although key components of the Hh pathway have been identified, significant gaps remain in our understanding of the regulation of individual Hh signaling molecules. Here, we report the identification of novel regulators of the Hh pathway, obtained from an in vivo RNA interference (RNAi screen in Drosophila. By selectively targeting critical genes functioning in post-translational modification systems utilizing ubiquitin (Ub and Ub-like proteins, we identify two novel genes (dUba3 and dUbc12 that negatively regulate Hh signaling activity. We provide in vivo and in vitro evidence illustrating that dUba3 and dUbc12 are essential components of the neddylation pathway; they function in an enzyme cascade to conjugate the ubiquitin-like NEDD8 modifier to Cullin proteins. Neddylation activates the Cullin-containing ubiquitin ligase complex, which in turn promotes the degradation of Cubitus interruptus (Ci, the downstream transcription factor of the Hh pathway. Our study reveals a conserved molecular mechanism of the neddylation pathway in Drosophila and sheds light on the complex post-translational regulations in Hh signaling.

  7. Optimization of linezolid treatment regimens for Gram-positive bacterial infections based on pharmacokinetic/pharmacodynamic analysis.

    Science.gov (United States)

    Yang, Minjie; Zhang, Jing; Chen, Yuancheng; Liang, Xiaoyu; Guo, Yan; Yu, Jicheng; Zhu, Demei; Zhang, Yingyuan

    2017-01-01

    To optimize linezolid treatment regimens for Gram-positive bacterial infections based on pharmacokinetic/pharmacodynamic analysis. The minimum inhibitory concentration (MIC) distribution of 572 Gram-positive strains from patients with clinically confirmed infections was analyzed. Using the Monte Carlo simulation method, the cumulative fraction of response and probability of target attainment were determined for linezolid regimens of 600 mg q.12h and q.8h Results: Linezolid dosage of 600 mg q.12h yielded >90% cumulative fraction of response and probability of target attainment for staphylococcal infections with an MIC of ≤1 mg/l, enterococcal infections with higher MIC values required 600 mg q.8h. Linezolid 600 mg q.12h is still the clinically recommended empirical dosage for Gram-positive bacterial infections. However, as bacterial MICs increase, 600 mg q.8h may be required to achieve better efficacy.

  8. C-reactive protein velocity to distinguish febrile bacterial infections from non-bacterial febrile illnesses in the emergency department

    OpenAIRE

    Paran, Yael; Yablecovitch, Doron; Choshen, Guy; Zeitlin, Ina; Rogowski, Ori; Ben-Ami, Ronen; Katzir, Michal; Saranga, Hila; Rosenzweig, Tovit; Justo, Dan; Orbach, Yaffa; Halpern, Pinhas; Berliner, Shlomo

    2009-01-01

    Introduction C-reactive protein (CRP) is a real-time and low-cost biomarker to distinguish febrile bacterial infections from non-bacterial febrile illnesses. We hypothesised that measuring the velocity of the biomarker instead of its absolute serum concentration could enhance its ability to differentiate between these two conditions. Methods We prospectively recruited adult patients (age ? 18 years) who presented to the emergency department with fever. We recorded their data regarding the ons...

  9. Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism *

    OpenAIRE

    Thompson, A.A.R.; Dickinson, R.S.; Murphy, F.; Thomson, J. P.; Marriott, H.M.; Tavares, A.; Willson, J.; Williams, L.; Lewis, A.; Mirchandani, A.; Dos Santos Coelho, P.; Doherty, C.; Ryan, E.; Watts, E.; Morton, N. M.

    2017-01-01

    Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer...

  10. Transmigration of polymorphnuclear neutrophils and monocytes through the human blood-cerebrospinal fluid barrier after bacterial infection in vitro.

    Science.gov (United States)

    Steinmann, Ulrike; Borkowski, Julia; Wolburg, Hartwig; Schröppel, Birgit; Findeisen, Peter; Weiss, Christel; Ishikawa, Hiroshi; Schwerk, Christian; Schroten, Horst; Tenenbaum, Tobias

    2013-02-28

    Bacterial invasion through the blood-cerebrospinal fluid barrier (BCSFB) during bacterial meningitis causes secretion of proinflammatory cytokines/chemokines followed by the recruitment of leukocytes into the CNS. In this study, we analyzed the cellular and molecular mechanisms of polymorphonuclear neutrophil (PMN) and monocyte transepithelial transmigration (TM) across the BCSFB after bacterial infection. Using an inverted transwell filter system of human choroid plexus papilloma cells (HIBCPP), we studied leukocyte TM rates, the migration route by immunofluorescence, transmission electron microscopy and focused ion beam/scanning electron microscopy, the secretion of cytokines/chemokines by cytokine bead array and posttranslational modification of the signal regulatory protein (SIRP) α via western blot. PMNs showed a significantly increased TM across HIBCPP after infection with wild-type Neisseria meningitidis (MC58). In contrast, a significantly decreased monocyte transmigration rate after bacterial infection of HIBCPP could be observed. Interestingly, in co-culture experiments with PMNs and monocytes, TM of monocytes was significantly enhanced. Analysis of paracellular permeability and transepithelial electrical resistance confirmed an intact barrier function during leukocyte TM. With the help of the different imaging techniques we could provide evidence for para- as well as for transcellular migrating leukocytes. Further analysis of secreted cytokines/chemokines showed a distinct pattern after stimulation and transmigration of PMNs and monocytes. Moreover, the transmembrane glycoprotein SIRPα was deglycosylated in monocytes, but not in PMNs, after bacterial infection. Our findings demonstrate that PMNs and monoctyes differentially migrate in a human BCSFB model after bacterial infection. Cytokines and chemokines as well as transmembrane proteins such as SIRPα may be involved in this process.

  11. Effect of auto-skin grafting on bacterial infection of wound in rats inflicted with combined radiation-burn injury

    International Nuclear Information System (INIS)

    Ran Xinze; Yan Yongtang; Wei Shuqing

    1992-01-01

    Rats were exposed to 6 Gy whole body γ-ray irradiation from a 60 Co source followed by light radiation burn (15% TBSA, full thickness burn) from a 5 kw bromo-tungsten lamp. The effect of auto-skin grafting on invasive bacterial infection of wound in the rats with combined radiation-burn injury was studied, In the control group inflicted with combined radiation-burn injury but without skin grafting, bacteria were found on and in the eschars at 24th hour after injury, and in the subeschar tissue on 3rd day. Tremendous bacterial multiplication occurred from 7th to 15th day, and the amount of bacteria in the internal organs increased along with the increase of subeschar infection. At the same time, no bacterial infection was found in internal organs in auto-skin grafted group at 24th hour after injury. The results show that skin grafting can decrease or prevent bacterial infection in both subeschar tissue and internal organs

  12. CD64 on monocytes and granulocytes in severe acute bronchiolitis: Pilot study on its usefulness as a bacterial infection biomarker.

    Science.gov (United States)

    García-Salido, Alberto; Serrano-González, Ana; Casado-Flores, Juan; Sierra-Colomina, Montserrat; de Azagra-Garde, Amelia Martínez; García-Teresa, María Ángeles; Melen, Gustavo J; Ramírez-Orellana, Manuel

    2018-02-27

    The CD64 receptor has been described as a biomarker of bacterial infection. We speculated that CD64 surface expression on monocytes and granulocytes of children with severe acute bronchiolitis (SAB) could be altered in cases of probable bacterial infection (PBI) determined using classical biomarkers (procalcitonin and C-reactive protein, leukocyte count, and radiographic findings). A prospective observational pilot study was conducted from October 2015 to February 2016 in children admitted for pediatric critical care. A blood sample was taken in the first 24 hours of admission, and CD64 was measured by flow cytometry. The values obtained were analyzed and correlated with traditional biomarkers of PBI. Thirty-two children were included; a correlation was found between CD64 expression and the PBI criteria. CD64 surface expression was higher in children with PBI (area under the receiver operating characteristic curve of 0.73; P = 0.042) and the percentage of CD64 + granulocytes was higher in children with PBI. This is the first study to describe CD64 surface expression on monocytes and granulocytes in SAB, finding CD64 values to be higher in children with PBI. Larger clinical studies are needed to elucidate the real accuracy of CD64 as a biomarker of bacterial infection. ©2018 Society for Leukocyte Biology.

  13. Cell array-based intracellular localization screening reveals novel functional features of human chromosome 21 proteins

    Directory of Open Access Journals (Sweden)

    Kahlem Pascal

    2006-06-01

    Full Text Available Abstract Background Trisomy of human chromosome 21 (Chr21 results in Down's syndrome, a complex developmental and neurodegenerative disease. Molecular analysis of Down's syndrome, however, poses a particular challenge, because the aneuploid region of Chr21 contains many genes of unknown function. Subcellular localization of human Chr21 proteins may contribute to further understanding of the functions and regulatory mechanisms of the genes that code for these proteins. Following this idea, we used a transfected-cell array technique to perform a rapid and cost-effective analysis of the intracellular distribution of Chr 21 proteins. Results We chose 89 genes that were distributed over the majority of 21q, ranging from RBM11 (14.5 Mb to MCM3AP (46.6 Mb, with part of them expressed aberrantly in the Down's syndrome mouse model. Open reading frames of these genes were cloned into a mammalian expression vector with an amino-terminal His6 tag. All of the constructs were arrayed on glass slides and reverse transfected into HEK293T cells for protein expression. Co-localization detection using a set of organelle markers was carried out for each Chr21 protein. Here, we report the subcellular localization properties of 52 proteins. For 34 of these proteins, their localization is described for the first time. Furthermore, the alteration in cell morphology and growth as a result of protein over-expression for claudin-8 and claudin-14 genes has been characterized. Conclusion The cell array-based protein expression and detection approach is a cost-effective platform for large-scale functional analyses, including protein subcellular localization and cell phenotype screening. The results from this study reveal novel functional features of human Chr21 proteins, which should contribute to further understanding of the molecular pathology of Down's syndrome.

  14. Development of aptamers for use as radiopharmaceuticals in the bacterial infection identification

    International Nuclear Information System (INIS)

    Ferreira, Ieda Mendes

    2013-01-01

    The difficulty in early detection of specific foci caused by bacteria in the bacterial infection has raised the need to search for new techniques for this purpose, since these foci require prolonged treatment with antibiotics and in some cases even drainage or, if applicable, removal of prostheses or grafts. Detection of bacterial infections by scintigraphy had the advantage that a whole body image could be obtained, since specific tracers were available. This study aims to obtain aptamers specific for bacteria identification for future use as radiopharmaceutical. The SELEX (Systematic Evolution of Ligands by Exponential Enrichment) methodology can generate oligonucleotides (aptamers) that are able to bind with high affinity and specificity to a specific target, from small molecules to complex proteins, by using rounds of enrichment and amplification. Aptamers can be labeled with different radionucleotides such as 99 mTc, 18 F and 32 P. In this study, aptamers anti-peptidoglycan, the main component of the bacterial outer cell wall, were obtained through SELEX. Whole cells of Staphylococcus aureus were also used to perform the SELEX to cells (cell-SELEX). The selection of aptamers was performed by two different procedures (A and B). The A process has been accomplished by 15 SELEX rounds in which the separation of the oligonucleotides bound to the peptidoglycan of unbound ones was performed by filtration. In the B process 15 SELEX rounds were performed using the centrifugation for this separation, followed by 5 rounds cell-SELEX. The SELEX started with a pool of ssDNA (single stranded DNA). For A process, initially a library of ssDNA was incubated with peptidoglycan and the amplification of oligonucleotides that were able to bind to peptidoglycan was performed by PCR (Polymerase Chain Reation). The amplified oligonucleotides were again incubated with peptidoglycan, amplified and purified. At the end of 15 selection rounds the selected oligonucleotides were cloned

  15. Low virulence bacterial infections in cervical intervertebral discs: a prospective case series.

    Science.gov (United States)

    Chen, Yilei; Wang, Xianjun; Zhang, Xuyang; Ren, Hong; Huang, Bao; Chen, Jian; Liu, Junhui; Shan, Zhi; Zhu, Zhihai; Zhao, Fengdong

    2018-04-19

    A prospective cross-sectional case series study. To investigate the prevalence of low virulence disc infection and its associations with characteristics of patients or discs in the cervical spine. Low virulence bacterial infections could be a possible cause of intervertebral disc degeneration and/or back pain. Controversies are continuing over whether these bacteria, predominantly Propionibacterium acnes (P. acnes), represent infection or contamination. However, the current studies mainly focus on the lumbar spine, with very limited data on the cervical spine. Thirty-two patients (20 men and 12 women) who underwent anterior cervical fusion for degenerative cervical spondylosis or traumatic cervical cord injury were enrolled. Radiological assessments included X-ray, CT, and MRI of the cervical spine. Endplate Modic changes, intervertebral range of motion, and disc herniation type were evaluated. Disc and muscle tissues were collected under strict sterile conditions. Samples were enriched in tryptone soy broth and subcultured under anaerobic conditions, followed by identification of the resulting colonies by the PCR method. Sixty-six intervertebral discs were excised from thirty-two patients. Positive disc cultures were noted in eight patients (25%) and in nine discs (13.6%). The muscle biopsy (control) cultures were negative in 28 patients and positive in 4 patients (12.5%); three of whom had a negative disc culture. Seven discs (10.6%) were positive for coagulase-negative Staphylococci (CNS) and two discs were positive for P. acnes (3.0%). A younger patient age and the extrusion or sequestration type of disc herniation, which represented a complete annulus fibrous failure, were associated with positive disc culture. Our data show that CNS is more prevalent than P. acnes in degenerative cervical discs. The infection route in cervical discs may be predominantly through an annulus fissure. Correlation between these infections and clinical symptoms is uncertain

  16. Multi-scale fluorescence imaging of bacterial infections in animal models

    Science.gov (United States)

    Bixler, Joel N.; Kong, Ying; Cirillo, Jeffrey D.; Maitland, Kristen C.

    2013-03-01

    Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), currently affects roughly one-third of the world's population. Drug resistant strains of Mtb decrease the effectiveness of current therapeutics and demand the development of new antimicrobial therapies. In addition, the current vaccine, Bacille Calmette Guérin (BCG), has variable efficacy for disease prevention in different populations. Animal studies are often limited by the need to sacrifice at discrete time points for pathology and tissue homogenization, which greatly reduces spatial and temporal resolution. Optical imaging offers the potential for a minimally-invasive solution to imaging on a macroscopic and microscopic scale, allowing for high resolution study of infection. We have integrated a fluorescence microendoscope into a whole-animal optical imaging system, allowing for simultaneous microscopic and macroscopic imaging of tdTomato expressing BCG in vivo. A 535 nm LED was collimated and launched into a 10,000 element fiber bundle with an outer diameter of 0.66 mm. The fiber bundle can be inserted through an intra-tracheal catheter into the lung of a mouse. Fluorescence emission can either be (1) collected by the bundle and imaged onto the surface of a CCD camera for localized detection or (2) the fluorescence can be imaged by the whole animal imaging system providing macroscopic information. Results from internal localized excitation and external whole body detection indicate the potential for imaging bacterial infections down to 100 colony forming units. This novel imaging technique has the potential to allow for functional studies, enhancing the ability to assess new therapeutic agents.

  17. Tracking bacterial infection of macrophages using a novel red-emission pH sensor.

    Science.gov (United States)

    Jin, Yuguang; Tian, Yanqing; Zhang, Weiwen; Jang, Sei-Hum; Jen, Alex K-Y; Meldrum, Deirdre R

    2010-10-01

    The relationship between bacteria and host phagocytic cells is key to the induction of immunity. To visualize and monitor bacterial infection, we developed a novel bacterial membrane permeable pH sensor for the noninvasive monitoring of bacterial entry into murine macrophages. The pH sensor was constructed using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) as an electron-withdrawing group and aniline as an electron-donating group. A piperazine moiety was used as the pH-sensitive group. Because of the strong electron-donating and -withdrawing units conjugated in the sensing moiety M, the fluorophore emitted in the red spectral window, away from the autofluorescence regions of the bacteria. Following the engulfment of sensor-labeled bacteria by macrophages and their subsequent merger with host lysosomes, the resulting low-pH environment enhances the fluorescence intensity of the pH sensors inside the bacteria. Time-lapse analysis of the fluorescent intensity suggested significant heterogeneity of bacterial uptake among macrophages. In addition, qRT-PCR analysis of the bacterial 16 S rRNA gene expression within single macrophage cells suggested that the 16 S rRNA of the bacteria was still intact 120 min after they had been engulfed by macrophages. A toxicity assay showed that the pH sensor has no cytotoxicity towards either E. coli or murine macrophages. The sensor shows good repeatability, a long lifetime, and a fast response to pH changes, and can be used for a variety of bacteria.

  18. Flow Cytometry Study of Lymphocyte Subsets in Malnourished and Well-Nourished Children with Bacterial Infections

    Science.gov (United States)

    Nájera, Oralia; González, Cristina; Toledo, Guadalupe; López, Laura; Ortiz, Rocío

    2004-01-01

    Protein-energy malnutrition is the primary cause of immune deficiency in children across the world. It has been related to changes in peripheral T-lymphocyte subsets. The aim of the present study was to evaluate the effects of infection and malnutrition on the proportion of peripheral-lymphocyte subsets in well-nourished non-bacterium-infected (WN), well-nourished bacterium-infected (WNI), and malnourished bacterium-infected (MNI) children by flow cytometry. A prospectively monitored cohort of 15 MNI, 12 WNI, and 17 WN children was studied. All the children were 3 years old or younger and had only bacterial infections. Results showed a significant decrease in the proportion of T CD3+ (P < 0.05 for relative and P < 0.03 for absolute values), CD4+ (P < 0.01 for relative and absolute values), and CD8+ (P < 0.05 for relative values) lymphocyte subsets in WNI children compared to the results seen with WN children. Additionally, B lymphocytes in MNI children showed significant lower values (CD20+ P < 0.02 for relative and P < 0.05 for absolute values) in relation to the results seen with WNI children. These results suggest that the decreased proportions of T-lymphocyte subsets observed in WNI children were associated with infection diseases and that the incapacity to increase the proportion of B lymphocyte was associated with malnutrition. This low proportion of B lymphocytes may be associated with the mechanisms involved in the immunodeficiency of malnourished children. PMID:15138185

  19. Label-free bimodal waveguide immunosensor for rapid diagnosis of bacterial infections in cirrhotic patients.

    Science.gov (United States)

    Maldonado, Jesús; González-Guerrero, Ana Belén; Domínguez, Carlos; Lechuga, Laura M

    2016-11-15

    Spontaneous bacterial peritonitis is an acute bacterial infection of ascitic fluid; it has a high incidence in cirrhotic patients and it is associated with high mortality. In such a situation, early diagnosis and treatment is crucial for the survival of the patient. However, bacterial analysis in ascitic fluid is currently based on culture methods, which are time-consuming and laborious. We report here the application of a photonic interferometer biosensor based on a bimodal waveguide (BiMW) for the rapid and label-free detection of bacteria directly in ascitic fluid. The device consists of a straight waveguide in which two modes of the same polarization interfere while interacting with the external medium through their evanescent fields. A bimolecular event occurring on the sensor area of the device (e.g. capturing bacteria) will differently affect each light mode, inducing a variation in the phase of the light exiting at the output of the waveguide. In this work, we demonstrate the quantitative detection of Bacillus cereus in buffer medium and Escherichia coli in undiluted ascitic fluid from cirrhotic patients. In the case of Bacillus cereus detection, the device was able to specifically detect bacteria at relevant concentrations in 12.5min and in the case of Escherichia coli detection, the analysis time was 25min. Extrapolation of the data demonstrated that the detection limits of the biosensor could reach few bacteria per milliliter. Based on the results obtained, we consider that the BiMW biosensor is positioned as a promising new clinical tool for user-friendly, cost-effective and real-time microbiological analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Duration of fever and markers of serious bacterial infection in young febrile children.

    Science.gov (United States)

    Pratt, Amanda; Attia, Magdy W

    2007-02-01

    Despite the drastic change in the evaluation of the febrile young child due to the decreased incidence of serious bacterial infections (SBI) effected by Haemophilus influenza type B and pneumococcal vaccine, there remains a small role for blood work in the evaluation of these patients. Bacterial markers including white blood cell (WBC) count, absolute neutrophil count (ANC) and C-reactive protein (CRP) have been studied and are widely used as predictors of SBI in febrile children. It has been suggested that CRP values should be interpreted cautiously when fever has been present predictors of SBI in relation to duration of fever. Patients who presented to a pediatric emergency department between the ages of 1 and 36 months, with fever > or =39 degrees C and no source of infection had a complete blood count (CBC) blood culture, and CRP level drawn. A urinalysis and/or urine culture was obtained when age and gender appropriate. A chest X-ray was performed at the discretion of the treating physician. The study subjects were enrolled prospectively and then divided into two groups based on duration of fever of 12 h, and compared. One hundred and twenty-eight patients were originally enrolled. Nine patients were excluded. Seventeen patients (14%) had SBI. One patient (urinary tract infections. Forty-five patients presented with fever 12 h. Area under the curve (AUC) for WBC, ANC and CRP was significantly larger in patients with SBI presenting with fever >12 h (0.85, 0.83, 0.92 respectively) compared to patients with SBI who presented with fever for 12 h as shown by the AUC. CRP performed better than WBC and ANC in both scenarios.

  1. Diagnostic testing for serious bacterial infections in infants aged 90 days or younger with bronchiolitis.

    Science.gov (United States)

    Liebelt, E L; Qi, K; Harvey, K

    1999-05-01

    %, and history of apnea were associated with laboratory testing for bacterial infections.

  2. Predictive model for serious bacterial infections among infants younger than 3 months of age.

    Science.gov (United States)

    Bachur, R G; Harper, M B

    2001-08-01

    To develop a data-derived model for predicting serious bacterial infection (SBI) among febrile infants /=38.0 degrees C seen in an urban emergency department (ED) were retrospectively identified. SBI was defined as a positive culture of urine, blood, or cerebrospinal fluid. Tree-structured analysis via recursive partitioning was used to develop the model. SBI or No-SBI was the dichotomous outcome variable, and age, temperature, urinalysis (UA), white blood cell (WBC) count, absolute neutrophil count, and cerebrospinal fluid WBC were entered as potential predictors. The model was tested by V-fold cross-validation. Of 5279 febrile infants studied, SBI was diagnosed in 373 patients (7%): 316 urinary tract infections (UTIs), 17 meningitis, and 59 bacteremia (8 with meningitis, 11 with UTIs). The model sequentially used 4 clinical parameters to define high-risk patients: positive UA, WBC count >/=20 000/mm(3) or /=39.6 degrees C, and age <13 days. The sensitivity of the model for SBI is 82% (95% confidence interval [CI]: 78%-86%) and the negative predictive value is 98.3% (95% CI: 97.8%-98.7%). The negative predictive value for bacteremia or meningitis is 99.6% (95% CI: 99.4%-99.8%). The relative risk between high- and low-risk groups is 12.1 (95% CI: 9.3-15.6). Sixty-six SBI patients (18%) were misclassified into the lower risk group: 51 UTIs, 14 with bacteremia, and 1 with meningitis. Decision-tree analysis using common clinical variables can reasonably predict febrile infants at high-risk for SBI. Sequential use of UA, WBC count, temperature, and age can identify infants who are at high risk of SBI with a relative risk of 12.1 compared with lower-risk infants.

  3. ROLE OF STREPTOCOCCUS PNEUMONIAE IN THE STRUCTURE OF BACTERIAL INFECTIONS IN THE CHILDREN HOSPITALIZED TO INPATIENT HOSPITALS IN MOSCOW IN 2011–2012

    Directory of Open Access Journals (Sweden)

    A. A. Baranov

    2013-01-01

    Full Text Available Data on the spread of Streptococcus pneumoniae serotypes in the RF are extremely limited. 3 pneumococcal conjugated vaccines are approved inRussia; however, neither has yet been employed in the framework of the national population immunization program. At the same time, it is the dataon the serotype range of pneumococcal infections that may be considered the prognostic efficacy criterion for the national vaccination programs.The objective of this research is identification of the circulating S. pneumoniae serotypes and spread of pneumococcal etiology infections in the structure of bacterial infections in the infants hospitalized to 5 inpatient hospital of Moscow in 2011–2012. The trial involved 864 patients in tote. Vast majority of patients (86% had acute purulent otitis media and sinusitis. Community-acquired pneumonia was diagnosed in 9% of patients, sepsis and bacteremia — in 3.6%; purulent meningitis — 1.2% of patients. It has been revealed that S. pneumoniae is the primary pathogen in the structure of nasopharyngeal carriage in the children under 5 years of age hospitalized with acute bacterial infections, and the primary bacterial causative agent of acute otitis media at this age. Nasopharyngeal pneumococcal carriage analysis revealed the prevalent serotypes — 19F, 14, 23F, 3, 6A and B; they were present in 3/4 of all cases; 19F was the most frequent (> 20%. Diversity of the S. pneumoniae serotypes detected in middle ear liquid was less significant — 17 serotypes (in comparison with 24 serotypes in nasopharynx. The 5 prevalent serotypes were 19F, 3, 14, 23F, 6B and 19A (> 75% in tote. Detection rate of serotypes 3 and 19A in middle ear liquid significantly exceeded the detection rate of these serotypes in case of nasopharyngeal carriage. The study of invasive infections revealed serotypes 14, 23F, 3 and 15C. These data may be used as a benchmark for future monitoring and evaluation of effect of PCV vaccines on epidemiology of

  4. BMI and breast cancer prognosis benefit: mammography screening reveals differences between normal weight and overweight women.

    Science.gov (United States)

    Crispo, Anna; Grimaldi, Maria; D'Aiuto, Massimiliano; Rinaldo, Massimo; Capasso, Immacolata; Amore, Alfonso; D'Aiuto, Giuseppe; Giudice, Aldo; Ciliberto, Gennaro; Montella, Maurizio

    2015-02-01

    Few studies are available on the potential impact of body weight on breast cancer prognosis in screen-detected patients. Moreover, it is not known whether body mass index (BMI) could have a different prognostic impact in screen-detected versus symptomatic breast cancer patients. To investigate these unsolved issues, we carried out a retrospective study evaluating the effect of BMI on breast cancer prognosis in screen-detected vs symptomatic breast cancer patients. We conducted a follow-up study on 448 women diagnosed with incident, histologically-confirmed breast cancer. Patients were categorized according to their BMI as normal weight, overweight and obese. Disease free survival (DFS), overall survival (OS), and BMI curves were compared according to mode of cancer detection. Among screen-detected patients, higher BMI was associated with a significant lower DFS, whereas no significant difference was observed among symptomatic patients. OS showed similar results. In the multivariate analysis adjusting for age, education, tumor size, nodal status, estrogen receptor (ER), progesterone receptor (PR) and menopausal status, the risk for high level of BMI among screen-detected patients did not reach the statistical significance for either recurrence or survival. Our study highlights the potential impact of high bodyweight in breast cancer prognosis, the findings confirm that obesity plays a role in women breast cancer prognosis independently from diagnosis mode. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Fungal and Bacterial Infection Mitigation with Antibiotic and Antifungal Loaded Biopolymer Sponges

    Science.gov (United States)

    Parker, Ashley Cox

    Musculoskeletal injuries are some of the most prevalent injuries in both civilian and military populations and their infections can be difficult to treat, often resulting in multiple surgeries and increased costs. In both previous and recent military operations, extremity injuries have been the most common battlefield injuries and many involve complex, open fractures. These extremity injuries are especially susceptible to multiple pathogenic, and sometimes drug resistant, bacteria and fungi. Fungal infections have recently become increasingly problematic in both military and civilian populations and have significantly higher amputation rates than those from bacterial infections. Many of these bacterial and fungal strains adhere to tissue and implanted orthopaedic hardware within wounds, forming biofilms. These problematic, often polymicrobial, infections threaten the health of the patient, but the risk also exists of spreading within hospitals to become prominent resistant infections. Local antimicrobial delivery releases high levels of antimicrobials directly to injured wound tissue, overcoming sub-bactericidal or subfungicidal antimicrobial levels present in the avascular wound zones. This research will determine the ability of modified chitosan sponges, buffered with sodium acetate or blended with polyethylene glycol (PEG), to act as short term adjunctive therapies to initial surgical treatment for delivering both antibiotics and/or antifungals for early abatement of infection. The objective of this work was to evaluate both types of modified sponges for in vitro and in vivo material characteristics and device functionality. In vitro analysis demonstrated both the buffered and PEG modified chitosan sponges exhibited increased degradation and functional cytocompatibility. The chitosan/PEG sponges were able to be loaded with hydrophobic antifungals and the sponges released in vitro biologically active concentrations, alone or in combination with the antibiotic

  6. The potential of methylethylpiridinol in treatment of bacterial infections caused by Klebsiella pneumoniae (experimental study

    Directory of Open Access Journals (Sweden)

    V. M. Brykhanov

    2016-01-01

    Full Text Available Aim. Investigated the activity of methylethylpiridinol (6-methyl-2-ethyl-pyridin-3-ol hydrochloride in the comprehensive treatment of the experimental bacterial infection caused by Klebsiella pneumoniae.Materials and methods. The study was conducted on clinical isolates of Klebsiella pneumoniae. At the first stage of the study (in vitro studied the effect of methylethylpiridinol in concentrations 0,25–4 mM on the growth of the strain and the activity of the sublethal concentrations of antibiotics – gentamicin, ciprofloxacin, tetracycline, ceftazidime. In the second stage of the study (in vivo in rats Wistar simulated bacterial peritonitis by intraperitoneal injection of a suspension of Klebsiella pneumoniae and investigated the effect of methylethylpiridinol (80 mg/kg on the effectiveness of antibiotic therapy with gentamicin (30 mg/kg, ciprofloxacin (50 mg/kg, ceftazidime (120 mg/kg or tetracycline (80 mg/kg. The animal blood plasma was determined ceruloplasmin concentration (marker of the intensity of infectious-inflammatory process and thiobarbiturate-jet products, erythrocytes – the concentration of reduced glutathione, catalase and glutathione peroxidase.Results. It is found that a methylethylpiridinol inhibits the development of periodic bacterial cultures, but exhibits a pronounced antagonism with respect to gentamicin. Antioxidant slightly increases the activity of ciprofloxacin and tetracycline. The bacteriostatic effect of antioxidant reduces the action of ceftazidime in vitro. In conditions of chemotherapy by using of gentamicin and ciprofloxacin additional injection of methylethylpiridinol leads to the preservation of ceruloplasmin level to the level of non-treated animals without showing the antioxidant effect. Ceftazidime exhibits antioxidant effect, reduces the introduction of methylethylpiridinol. The antioxidant properties of methylethylpiridinol did not appear in the application of

  7. RNA Transcriptional Biosignature Analysis for Identifying Febrile Infants With Serious Bacterial Infections in the Emergency Department

    Science.gov (United States)

    Mahajan, Prashant; Kuppermann, Nathan; Suarez, Nicolas; Mejias, Asuncion; Casper, Charlie; Dean, J. Michael; Ramilo, Octavio

    2015-01-01

    Objectives To develop the infrastructure and demonstrate the feasibility of conducting microarray-based RNA transcriptional profile analyses for the diagnosis of serious bacterial infections in febrile infants 60 days and younger in a multicenter pediatric emergency research network. Methods We designed a prospective multicenter cohort study with the aim of enrolling more than 4000 febrile infants 60 days and younger. To ensure success of conducting complex genomic studies in emergency department (ED) settings, we established an infrastructure within the Pediatric Emergency Care Applied Research Network, including 21 sites, to evaluate RNA transcriptional profiles in young febrile infants. We developed a comprehensive manual of operations and trained site investigators to obtain and process blood samples for RNA extraction and genomic analyses. We created standard operating procedures for blood sample collection, processing, storage, shipping, and analyses. We planned to prospectively identify, enroll, and collect 1 mL blood samples for genomic analyses from eligible patients to identify logistical issues with study procedures. Finally, we planned to batch blood samples and determined RNA quantity and quality at the central microarray laboratory and organized data analysis with the Pediatric Emergency Care Applied Research Network data coordinating center. Below we report on establishment of the infrastructure and the feasibility success in the first year based on the enrollment of a limited number of patients. Results We successfully established the infrastructure at 21 EDs. Over the first 5 months we enrolled 79% (74 of 94) of eligible febrile infants. We were able to obtain and ship 1 mL of blood from 74% (55 of 74) of enrolled participants, with at least 1 sample per participating ED. The 55 samples were shipped and evaluated at the microarray laboratory, and 95% (52 of 55) of blood samples were of adequate quality and contained sufficient RNA for expression

  8. Characterization of CRISPR-Cas system in clinical Staphylococcus epidermidis strains revealed its potential association with bacterial infection sites

    DEFF Research Database (Denmark)

    Li, Qiuchun; Xie, Xiaolei; Yin, Kequan

    2016-01-01

    Staphylococcus epidermidis is considered as a major cause of nosocomial infections, bringing an immense burden to healthcare systems. Virulent phages have been confirmed to be efficient in combating the pathogen, but the prensence of CRISPR-Cas system, which is a bacterial immune system eliminating...... phages was reported in few S. epidermidis strains. In this study, the CRISPR-Cas system was detected in 12 from almost 300 published genomes in GenBank and by PCR of cas6 gene in 18 strains out of 130 clinical isolates obtained in Copenhagen. Four strains isolated in 1965-1966 harboured CRISPR elements...... spacers located in the CRISPR1 locus with homolgy to virulent phage 6ec DNA sequences, and 19 strains each carrying 2 or 3 different spacers recognizing this phage, implied that the CRISPR-Cas immunity could be abrogated by nucleotide mismatch between the spacer and its target phage sequence, while new...

  9. A Tendon Cell Specific RNAi Screen Reveals Novel Candidates Essential for Muscle Tendon Interaction.

    Directory of Open Access Journals (Sweden)

    Prabhat Tiwari

    Full Text Available Tendons are fibrous connective tissue which connect muscles to the skeletal elements thus acting as passive transmitters of force during locomotion and provide appropriate body posture. Tendon-derived cues, albeit poorly understood, are necessary for proper muscle guidance and attachment during development. In the present study, we used dorsal longitudinal muscles of Drosophila and their tendon attachment sites to unravel the molecular nature of interactions between muscles and tendons. We performed a genetic screen using RNAi-mediated knockdown in tendon cells to find out molecular players involved in the formation and maintenance of myotendinous junction and found 21 candidates out of 2507 RNAi lines screened. Of these, 19 were novel molecules in context of myotendinous system. Integrin-βPS and Talin, picked as candidates in this screen, are known to play important role in the cell-cell interaction and myotendinous junction formation validating our screen. We have found candidates with enzymatic function, transcription activity, cell adhesion, protein folding and intracellular transport function. Tango1, an ER exit protein involved in collagen secretion was identified as a candidate molecule involved in the formation of myotendinous junction. Tango1 knockdown was found to affect development of muscle attachment sites and formation of myotendinous junction. Tango1 was also found to be involved in secretion of Viking (Collagen type IV and BM-40 from hemocytes and fat cells.

  10. A Genome-wide multidimensional RNAi screen reveals pathways controlling MHC class II antigen presentation

    NARCIS (Netherlands)

    Paul, Petra; van den Hoorn, Tineke; Jongsma, Marlieke L. M.; Bakker, Mark J.; Hengeveld, Rutger; Janssen, Lennert; Cresswell, Peter; Egan, David A.; van Ham, Marieke; ten Brinke, Anja; Ovaa, Huib; Beijersbergen, Roderick L.; Kuijl, Coenraad; Neefjes, Jacques

    2011-01-01

    MHC class II molecules (MHC-II) present peptides to T helper cells to facilitate immune responses and are strongly linked to autoimmune diseases. To unravel processes controlling MHC-II antigen presentation, we performed a genome-wide flow cytometry-based RNAi screen detecting MHC-II expression and

  11. Clinical prediction model to aid emergency doctors managing febrile children at risk of serious bacterial infections: diagnostic study

    Science.gov (United States)

    Nijman, Ruud G; Vergouwe, Yvonne; Thompson, Matthew; van Veen, Mirjam; van Meurs, Alfred H J; van der Lei, Johan; Steyerberg, Ewout W; Moll, Henriette A

    2013-01-01

    Objective To derive, cross validate, and externally validate a clinical prediction model that assesses the risks of different serious bacterial infections in children with fever at the emergency department. Design Prospective observational diagnostic study. Setting Three paediatric emergency care units: two in the Netherlands and one in the United Kingdom. Participants Children with fever, aged 1 month to 15 years, at three paediatric emergency care units: Rotterdam (n=1750) and the Hague (n=967), the Netherlands, and Coventry (n=487), United Kingdom. A prediction model was constructed using multivariable polytomous logistic regression analysis and included the predefined predictor variables age, duration of fever, tachycardia, temperature, tachypnoea, ill appearance, chest wall retractions, prolonged capillary refill time (>3 seconds), oxygen saturation rule out the presence of other SBIs. Discriminative ability (C statistic) to predict pneumonia was 0.81 (95% confidence interval 0.73 to 0.88); for other SBIs this was even better: 0.86 (0.79 to 0.92). Risk thresholds of 10% or more were useful to identify children with serious bacterial infections; risk thresholds less than 2.5% were useful to rule out the presence of serious bacterial infections. External validation showed good discrimination for the prediction of pneumonia (0.81, 0.69 to 0.93); discriminative ability for the prediction of other SBIs was lower (0.69, 0.53 to 0.86). Conclusion A validated prediction model, including clinical signs, symptoms, and C reactive protein level, was useful for estimating the likelihood of pneumonia and other SBIs in children with fever, such as septicaemia/meningitis and urinary tract infections. PMID:23550046

  12. Bacterial infections in patients with liver cirrhosis: clinical characteristics and the role of C-reactive protein

    Science.gov (United States)

    Deutsch, Melanie; Manolakopoulos, Spilios; Andreadis, Ioannis; Giannaris, Markos; Kontos, George; Kranidioti, Hariklia; Pirounaki, Maria; Koskinas, John

    2018-01-01

    Background: The diagnosis of bacterial infection in cirrhotic patients may be difficult, because of the absence of classical signs such as fever and raised white blood cell count. The role of C-reactive protein (CRP) in this context has not been clearly defined. Methods: Clinical and laboratory characteristics of 210 consecutive cirrhotic patients with (n=100) or without (n=110) bacterial infection were compared with a control group of non-cirrhotic patients with infection (n=106). Results: Significantly fewer patients with cirrhosis had a body temperature ≥37°C when presenting with bacterial infection (56% cirrhotic vs. 85.5% non-cirrhotic patients, P=0.01). Mean leukocyte count was 6.92 × 103/mm3 in patients with cirrhosis and infection, 5.75 × 103/mm3 (P=0.02) in cirrhotic patients without infection, and 11.28 × 103/mm3 in non-cirrhotic patients with infection (P10 mg/L indicated the presence of infection with a sensitivity of 68%, a specificity of 84.5% and an area under the receiver operating characteristic curve of 0.8197. CRP cutoff level differed according to the severity of the liver disease: Child-Pugh score (CPS) A: 21.3 mg/L, B: 17 mg/L, and C: 5.78 mg/L. Conclusions: CRP at admission could help diagnose infection in cirrhotic patients. Since the severity of liver disease seems to affect the CRP values, lower CRP levels might indicate infection. Clinical suspicion is necessary to avoid delay in diagnosis and initiate antibiotic treatment. PMID:29333070

  13. Evaluation by biodistribution of two anti-peptidoglycan aptamers labeled with Technetium-99m for in vivo bacterial infection identification

    International Nuclear Information System (INIS)

    Ferreira, Iêda M.; Lacerda, Camila M.S.; Santos, Sara R.; Andrade, Antero S.R. de; Fernandes, Simone O.; Barros, André B. de; Cardoso, Valbert N.

    2017-01-01

    Nuclear medicine clinics are still awaiting optimal scintigraphic imaging agents capable of discriminating between infection and inflammation, and between fungal and bacterial infections. Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. In the present study, two aptamers for peptidoglycan (termed Antibac1 and Antibac2) were labeled with 99m Tc and evaluated for bacterial infection identification by biodistribution. The direct labeling method with 99m Tc allowed radiolabel yields higher than 90% and the complexes were stable in saline, plasma and cysteine excess. The 99m Tc-Antibac1 in the group infected with S. aureus presented a target/non-target ratio (T/NT) of 2.81 ± 0.67, significantly higher than verified for the 99m Tc-library (control): 1.52 ± 0.07. A radiolabeled library of oligonucleotides with random sequences was used as a control for monitoring nonspecific uptake at the site of infection. In the model with C. albicans infection the T/NT ratio for 99m Tc-Antibac1 was 1.46 ± 0.11, similar that obtained for the 99m Tc-library in the same model: 1.52 ± 0.05. The 99m Tc-Antibac2 in the group infected with S. aureus showed a T/NT ratio of 2.61 ± 0.66, statistically higher than achieved for the 99m Tc-library: 1.52 ± 0.07. In the group infected with C. albicans this ratio for 99m Tc-Antibac2 was 1.75 ± 0.19, also statistically higher in relation to the 99m Tc-library: 1.52 ± 0.05. Both aptamers were effective in identifying bacterial infection foci, but only 99m Tc-Antibac1 showed no cross reactivity for fungal cells. (author)

  14. Bacterial infections in patients with liver cirrhosis: clinical characteristics and the role of C-reactive protein.

    Science.gov (United States)

    Deutsch, Melanie; Manolakopoulos, Spilios; Andreadis, Ioannis; Giannaris, Markos; Kontos, George; Kranidioti, Hariklia; Pirounaki, Maria; Koskinas, John

    2018-01-01

    The diagnosis of bacterial infection in cirrhotic patients may be difficult, because of the absence of classical signs such as fever and raised white blood cell count. The role of C-reactive protein (CRP) in this context has not been clearly defined. Clinical and laboratory characteristics of 210 consecutive cirrhotic patients with (n=100) or without (n=110) bacterial infection were compared with a control group of non-cirrhotic patients with infection (n=106). Significantly fewer patients with cirrhosis had a body temperature ≥37°C when presenting with bacterial infection (56% cirrhotic vs. 85.5% non-cirrhotic patients, P=0.01). Mean leukocyte count was 6.92 × 10 3 /mm 3 in patients with cirrhosis and infection, 5.75 × 10 3 /mm 3 (P=0.02) in cirrhotic patients without infection, and 11.28 × 10 3 /mm 3 in non-cirrhotic patients with infection (P10 mg/L indicated the presence of infection with a sensitivity of 68%, a specificity of 84.5% and an area under the receiver operating characteristic curve of 0.8197. CRP cutoff level differed according to the severity of the liver disease: Child-Pugh score (CPS) A: 21.3 mg/L, B: 17 mg/L, and C: 5.78 mg/L. CRP at admission could help diagnose infection in cirrhotic patients. Since the severity of liver disease seems to affect the CRP values, lower CRP levels might indicate infection. Clinical suspicion is necessary to avoid delay in diagnosis and initiate antibiotic treatment.

  15. Inflammasome and Fas-Mediated IL-1β Contributes to Th17/Th1 Cell Induction in Pathogenic Bacterial Infection In Vivo.

    Science.gov (United States)

    Uchiyama, Ryosuke; Yonehara, Shin; Taniguchi, Shun'ichiro; Ishido, Satoshi; Ishii, Ken J; Tsutsui, Hiroko

    2017-08-01

    CD4 + Th cells play crucial roles in orchestrating immune responses against pathogenic microbes, after differentiating into effector subsets. Recent research has revealed the importance of IFN-γ and IL-17 double-producing CD4 + Th cells, termed Th17/Th1 cells, in the induction of autoimmune and inflammatory diseases. In addition, Th17/Th1 cells are involved in the regulation of infection caused by the intracellular bacterium Mycobacterium tuberculosis in humans. However, the precise mechanism of Th17/Th1 induction during pathogen infection is unclear. In this study, we showed that the inflammasome and Fas-dependent IL-1β induces Th17/Th1 cells in mice, in response to infection with the pathogenic intracellular bacterium Listeria monocytogenes In the spleens of infected wild-type mice, Th17/Th1 cells were induced, and expressed T-bet and Rorγt. In Pycard -/- mice, which lack the adaptor molecule of the inflammasome (apoptosis-associated speck-like protein containing a caspase recruitment domain), Th17/Th1 induction was abolished. In addition, the Fas-mediated IL-1β production was required for Th17/Th1 induction during bacterial infection: Th17/Th1 induction was abolished in Fas -/- mice, whereas supplementation with recombinant IL-1β restored Th17/Th1 induction via IL-1 receptor 1 (IL-1R1), and rescued the mortality of Fas -/- mice infected with Listeria IL-1R1, but not apoptosis-associated speck-like protein containing a caspase recruitment domain or Fas on T cells, was required for Th17/Th1 induction, indicating that IL-1β stimulates IL-1R1 on T cells for Th17/Th1 induction. These results indicate that IL-1β, produced by the inflammasome and Fas-dependent mechanisms, contributes cooperatively to the Th17/Th1 induction during bacterial infection. This study provides a deeper understanding of the molecular mechanisms underlying Th17/Th1 induction during pathogenic microbial infections in vivo. Copyright © 2017 by The American Association of Immunologists

  16. The Value of the “Lab-Score” Method in Identifying Febrile Infants at Risk for Serious Bacterial Infections

    Directory of Open Access Journals (Sweden)

    Moldovan Diana Aniela

    2015-03-01

    Full Text Available Introduction: Most children with fever without source will have a self limited viral infection though a small percent will develop a serious bacterial infection (SBI like urinary tract infection, pneumonia, bacteraemia, meningitis or sepsis. The challenge facing practitioners is to distinguish between these two groups and currently biomarkers, like C-reactive protein (CRP and Procalcitonin (PCT, are available for this purpose. The aim of the current study was to identify SBI in infants with fever without an identifiable cause using the recently introduced “Lab-score” combining C-reactive protein, procalcitonin and urine dipstick results.

  17. Broad-spectrum antibiotic or G-CSF as potential countermeasures for impaired control of bacterial infection associated with an SPE exposure during spaceflight.

    Directory of Open Access Journals (Sweden)

    Minghong Li

    Full Text Available A major risk for astronauts during prolonged space flight is infection as a result of the combined effects of microgravity, situational and confinement stress, alterations in food intake, altered circadian rhythm, and radiation that can significantly impair the immune system and the body's defense systems. We previously reported a massive increase in morbidity with a decrease in the ability to control a bacterial challenge when mice were maintained under hindlimb suspension (HS conditions and exposed to solar particle event (SPE-like radiation. HS and SPE-like radiation treatment alone resulted in a borderline significant increase in morbidity. Therefore, development and testing of countermeasures that can be used during extended space missions in the setting of exposure to SPE radiation becomes a serious need. In the present study, we investigated the efficacy of enrofloxacin (an orally bioavailable antibiotic and Granulocyte colony stimulating factor (G-CSF (Neulasta on enhancing resistance to Pseudomonas aeruginosa infection in mice subjected to HS and SPE-like radiation. The results revealed that treatment with enrofloxacin or G-CSF enhanced bacterial clearance and significantly decreased morbidity and mortality in challenged mice exposed to suspension and radiation. These results establish that antibiotics, such as enrofloxacin, and G-CSF could be effective countermeasures to decrease the risk of bacterial infections after exposure to SPE radiation during extended space flight, thereby reducing both the risk to the crew and the danger of mission failure.

  18. BTLA interaction with HVEM expressed on CD8(+ T cells promotes survival and memory generation in response to a bacterial infection.

    Directory of Open Access Journals (Sweden)

    Marcos W Steinberg

    Full Text Available The B and T lymphocyte attenuator (BTLA is an Ig super family member that binds to the herpes virus entry mediator (HVEM, a TNF receptor super family (TNFRSF member. Engagement of BTLA by HVEM triggers inhibitory signals, although recent evidence indicates that BTLA also may act as an activating ligand for HVEM. In this study, we reveal a novel role for the BTLA-HVEM pathway in promoting the survival of activated CD8(+ T cells in the response to an oral microbial infection. Our data show that both BTLA- and HVEM-deficient mice infected with Listeria monocytogenes had significantly reduced numbers of primary effector and memory CD8(+ T cells, despite normal proliferation and expansion compared to controls. In addition, blockade of the BTLA-HVEM interaction early in the response led to significantly reduced numbers of antigen-specific CD8(+ T cells. HVEM expression on the CD8(+ T cells as well as BTLA expression on a cell type other than CD8(+ T lymphocytes, was required. Collectively, our data demonstrate that the function of the BTLA-HVEM pathway is not limited to inhibitory signaling in T lymphocytes, and instead, that BTLA can provide crucial, HVEM-dependent signals that promote survival of antigen activated CD8(+ T cell during bacterial infection.

  19. BTLA interaction with HVEM expressed on CD8(+) T cells promotes survival and memory generation in response to a bacterial infection.

    Science.gov (United States)

    Steinberg, Marcos W; Huang, Yujun; Wang-Zhu, Yiran; Ware, Carl F; Cheroutre, Hilde; Kronenberg, Mitchell

    2013-01-01

    The B and T lymphocyte attenuator (BTLA) is an Ig super family member that binds to the herpes virus entry mediator (HVEM), a TNF receptor super family (TNFRSF) member. Engagement of BTLA by HVEM triggers inhibitory signals, although recent evidence indicates that BTLA also may act as an activating ligand for HVEM. In this study, we reveal a novel role for the BTLA-HVEM pathway in promoting the survival of activated CD8(+) T cells in the response to an oral microbial infection. Our data show that both BTLA- and HVEM-deficient mice infected with Listeria monocytogenes had significantly reduced numbers of primary effector and memory CD8(+) T cells, despite normal proliferation and expansion compared to controls. In addition, blockade of the BTLA-HVEM interaction early in the response led to significantly reduced numbers of antigen-specific CD8(+) T cells. HVEM expression on the CD8(+) T cells as well as BTLA expression on a cell type other than CD8(+) T lymphocytes, was required. Collectively, our data demonstrate that the function of the BTLA-HVEM pathway is not limited to inhibitory signaling in T lymphocytes, and instead, that BTLA can provide crucial, HVEM-dependent signals that promote survival of antigen activated CD8(+) T cell during bacterial infection.

  20. Screening Bioactives Reveals Nanchangmycin as a Broad Spectrum Antiviral Active against Zika Virus

    OpenAIRE

    Rausch, Keiko; Hackett, Brent A.; Weinbren, Nathan L.; Reeder, Sophia M.; Sadovsky, Yoel; Hunter, Christopher A.; Schultz, David C.; Coyne, Carolyn B.; Cherry, Sara

    2017-01-01

    Zika virus is an emerging arthropod-borne flavivirus for which there are no vaccines or specific therapeutics. We screened a library of 2,000 bioactive compounds for their ability to block Zika virus infection in three distinct cell types with two different strains of Zika virus. Using a microscopy-based assay, we validated 38 drugs that inhibited Zika virus infection, including FDA-approved nucleoside analogs. Cells expressing high levels of the attachment factor AXL can be protected from in...

  1. Visual screening for localized RNAs in yeast revealed novel RNAs at the bud-tip

    International Nuclear Information System (INIS)

    Andoh, Tomoko; Oshiro, Yukiko; Hayashi, Sachiko; Takeo, Hideki; Tani, Tokio

    2006-01-01

    Several RNAs, including rRNAs, snRNAs, snoRNAs, and some mRNAs, are known to be localized at specific sites in a cell. Although methods have been established to visualize RNAs in a living cell, no large-scale visual screening of localized RNAs has been performed. In this study, we constructed a genomic library in which random genomic fragments were inserted downstream of U1A-tag sequences under a GAL1 promoter. In a living yeast cell, transcribed U1A-tagged RNAs were visualized by U1A-GFP that binds the RNA sequence of the U1A-tag. In this screening, many RNAs showed nuclear signals. Since the nuclear signals of some RNAs were not seen when the U1A-tag was connected to the 3' ends of the RNAs, it is suggested that their nuclear signals correspond to nascent transcripts on GAL1 promoter plasmids. Using this screening method, we successfully identified two novel localized mRNAs, CSR2 and DAL81, which showed bud-tip localization

  2. A Systematic Protein Refolding Screen Method using the DGR Approach Reveals that Time and Secondary TSA are Essential Variables.

    Science.gov (United States)

    Wang, Yuanze; van Oosterwijk, Niels; Ali, Ameena M; Adawy, Alaa; Anindya, Atsarina L; Dömling, Alexander S S; Groves, Matthew R

    2017-08-24

    Refolding of proteins derived from inclusion bodies is very promising as it can provide a reliable source of target proteins of high purity. However, inclusion body-based protein production is often limited by the lack of techniques for the detection of correctly refolded protein. Thus, the selection of the refolding conditions is mostly achieved using trial and error approaches and is thus a time-consuming process. In this study, we use the latest developments in the differential scanning fluorimetry guided refolding approach as an analytical method to detect correctly refolded protein. We describe a systematic buffer screen that contains a 96-well primary pH-refolding screen in conjunction with a secondary additive screen. Our research demonstrates that this approach could be applied for determining refolding conditions for several proteins. In addition, it revealed which "helper" molecules, such as arginine and additives are essential. Four different proteins: HA-RBD, MDM2, IL-17A and PD-L1 were used to validate our refolding approach. Our systematic protocol evaluates the impact of the "helper" molecules, the pH, buffer system and time on the protein refolding process in a high-throughput fashion. Finally, we demonstrate that refolding time and a secondary thermal shift assay buffer screen are critical factors for improving refolding efficiency.

  3. Investigation of 6-[¹⁸F]-fluoromaltose as a novel PET tracer for imaging bacterial infection.

    Directory of Open Access Journals (Sweden)

    Gayatri Gowrishankar

    Full Text Available Despite advances in the field of nuclear medicine, the imaging of bacterial infections has remained a challenge. The existing reagents suffer from poor sensitivity and specificity. In this study we investigate the potential of a novel PET (positron emission tomography tracer that overcomes these limitations.6-[¹⁸F]-fluoromaltose was synthesized. Its behavior in vitro was evaluated in bacterial and mammalian cultures. Detailed pharmacokinetic and biodistribution profiles for the tracer were obtained from a murine model.6-[¹⁸F]-fluoromaltose is taken up by multiple strains of pathogenic bacteria. It is not taken up by mammalian cancer cell lines. 6-[¹⁸F]-fluoromaltose is retained in infected muscles in a murine model of bacterial myositis. It does not accumulate in inflamed tissue.We have shown that 6-[¹⁸F]-fluoromaltose can be used to image bacterial infection in vivo with high specificity. We believe that this class of agents will have a significant impact on the clinical management of patients.

  4. S-layer proteins from Lactobacillus sp. inhibit bacterial infection by blockage of DC-SIGN cell receptor.

    Science.gov (United States)

    Prado Acosta, Mariano; Ruzal, Sandra M; Cordo, Sandra M

    2016-11-01

    Many species of Lactobacillus sp. possess Surface(s) layer proteins in their envelope. Among other important characteristics S-layer from Lactobacillus acidophilus binds to the cellular receptor DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin; CD209), which is involved in adhesion and infection of several families of bacteria. In this report we investigate the activity of new S-layer proteins from the Lactobacillus family (Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus helveticus and Lactobacillus kefiri) over the infection of representative microorganisms important to human health. After the treatment of DC-SIGN expressing cells with these proteins, we were able to diminish bacterial infection by up to 79% in both gram negative and mycobacterial models. We discovered that pre-treatment of the bacteria with S-layers from Lactobacillus acidophilus and Lactobacillus brevis reduced bacteria viability but also prevent infection by the pathogenic bacteria. We also proved the importance of the glycosylation of the S-layer from Lactobacillus kefiri in the binding to the receptor and thus inhibition of infection. This novel characteristic of the S-layers proteins may contribute to the already reported pathogen exclusion activity for these Lactobacillus probiotic strains; and might be also considered as a novel enzymatic antimicrobial agents to inhibit bacterial infection and entry to host cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Screening the budding yeast genome reveals unique factors affecting K2 toxin susceptibility.

    Science.gov (United States)

    Servienė, Elena; Lukša, Juliana; Orentaitė, Irma; Lafontaine, Denis L J; Urbonavičius, Jaunius

    2012-01-01

    Understanding how biotoxins kill cells is of prime importance in biomedicine and the food industry. The budding yeast (S. cerevisiae) killers serve as a convenient model to study the activity of biotoxins consistently supplying with significant insights into the basic mechanisms of virus-host cell interactions and toxin entry into eukaryotic target cells. K1 and K2 toxins are active at the cell wall, leading to the disruption of the plasma membrane and subsequent cell death by ion leakage. K28 toxin is active in the cell nucleus, blocking DNA synthesis and cell cycle progression, thereby triggering apoptosis. Genome-wide screens in the budding yeast S. cerevisiae identified several hundred effectors of K1 and K28 toxins. Surprisingly, no such screen had been performed for K2 toxin, the most frequent killer toxin among industrial budding yeasts. We conducted several concurrent genome-wide screens in S. cerevisiae and identified 332 novel K2 toxin effectors. The effectors involved in K2 resistance and hypersensitivity largely map in distinct cellular pathways, including cell wall and plasma membrane structure/biogenesis and mitochondrial function for K2 resistance, and cell wall stress signaling and ion/pH homeostasis for K2 hypersensitivity. 70% of K2 effectors are different from those involved in K1 or K28 susceptibility. Our work demonstrates that despite the fact that K1 and K2 toxins share some aspects of their killing strategies, they largely rely on different sets of effectors. Since the vast majority of the host factors identified here is exclusively active towards K2, we conclude that cells have acquired a specific K2 toxin effectors set. Our work thus indicates that K1 and K2 have elaborated different biological pathways and provides a first step towards the detailed characterization of K2 mode of action.

  6. Revealing molecular mechanisms by integrating high-dimensional functional screens with protein interaction data.

    Directory of Open Access Journals (Sweden)

    Angela Simeone

    2014-09-01

    Full Text Available Functional genomics screens using multi-parametric assays are powerful approaches for identifying genes involved in particular cellular processes. However, they suffer from problems like noise, and often provide little insight into molecular mechanisms. A bottleneck for addressing these issues is the lack of computational methods for the systematic integration of multi-parametric phenotypic datasets with molecular interactions. Here, we present Integrative Multi Profile Analysis of Cellular Traits (IMPACT. The main goal of IMPACT is to identify the most consistent phenotypic profile among interacting genes. This approach utilizes two types of external information: sets of related genes (IMPACT-sets and network information (IMPACT-modules. Based on the notion that interacting genes are more likely to be involved in similar functions than non-interacting genes, this data is used as a prior to inform the filtering of phenotypic profiles that are similar among interacting genes. IMPACT-sets selects the most frequent profile among a set of related genes. IMPACT-modules identifies sub-networks containing genes with similar phenotype profiles. The statistical significance of these selections is subsequently quantified via permutations of the data. IMPACT (1 handles multiple profiles per gene, (2 rescues genes with weak phenotypes and (3 accounts for multiple biases e.g. caused by the network topology. Application to a genome-wide RNAi screen on endocytosis showed that IMPACT improved the recovery of known endocytosis-related genes, decreased off-target effects, and detected consistent phenotypes. Those findings were confirmed by rescreening 468 genes. Additionally we validated an unexpected influence of the IGF-receptor on EGF-endocytosis. IMPACT facilitates the selection of high-quality phenotypic profiles using different types of independent information, thereby supporting the molecular interpretation of functional screens.

  7. A genetic screen reveals a periplasmic copper chaperone required for nitrite reductase activity in pathogenic Neisseria.

    Science.gov (United States)

    Jen, Freda E-C; Djoko, Karrera Y; Bent, Stephen J; Day, Christopher J; McEwan, Alastair G; Jennings, Michael P

    2015-09-01

    Under conditions of low oxygen availability, Neisseria meningitidis and Neisseria gonorrhoeae are able to respire via a partial denitrification pathway in which nitrite is converted to nitrous oxide. In this process, nitrite reductase (AniA), a copper (Cu)-containing protein converts nitrite to NO, and this product is converted to nitrous oxide by nitric oxide reductase (NorB). NorB also confers protection against toxic NO, and so we devised a conditional lethal screen, using a norB mutant, to identify mutants that were resistant to nitrite-dependent killing. After random-deletion mutagenesis of N. meningitidis, this genetic screen identified a gene encoding a Cu chaperone that is essential for AniA function, AccA. Purified AccA binds one Cu (I) ion and also possesses a second binding site for Cu (II). This novel periplasmic Cu chaperone (AccA) appears to be essential for provision of Cu ions to AniA of pathogenic Neisseria to generate an active nitrite reductase. Apart from the Neisseria genus, AccA is distributed across a wide range of environmental Proteobacteria species. © FASEB.

  8. Comparative genetic screens in human cells reveal new regulatory mechanisms in WNT signaling

    Science.gov (United States)

    Lebensohn, Andres M; Dubey, Ramin; Neitzel, Leif R; Tacchelly-Benites, Ofelia; Yang, Eungi; Marceau, Caleb D; Davis, Eric M; Patel, Bhaven B; Bahrami-Nejad, Zahra; Travaglini, Kyle J; Ahmed, Yashi; Lee, Ethan; Carette, Jan E; Rohatgi, Rajat

    2016-01-01

    The comprehensive understanding of cellular signaling pathways remains a challenge due to multiple layers of regulation that may become evident only when the pathway is probed at different levels or critical nodes are eliminated. To discover regulatory mechanisms in canonical WNT signaling, we conducted a systematic forward genetic analysis through reporter-based screens in haploid human cells. Comparison of screens for negative, attenuating and positive regulators of WNT signaling, mediators of R-spondin-dependent signaling and suppressors of constitutive signaling induced by loss of the tumor suppressor adenomatous polyposis coli or casein kinase 1α uncovered new regulatory features at most levels of the pathway. These include a requirement for the transcription factor AP-4, a role for the DAX domain of AXIN2 in controlling β-catenin transcriptional activity, a contribution of glycophosphatidylinositol anchor biosynthesis and glypicans to R-spondin-potentiated WNT signaling, and two different mechanisms that regulate signaling when distinct components of the β-catenin destruction complex are lost. The conceptual and methodological framework we describe should enable the comprehensive understanding of other signaling systems. DOI: http://dx.doi.org/10.7554/eLife.21459.001 PMID:27996937

  9. Screening in larval zebrafish reveals tissue-specific distribution of fifteen fluorescent compounds

    Directory of Open Access Journals (Sweden)

    Yuxiao Yao

    2017-09-01

    Full Text Available The zebrafish is a prominent vertebrate model for low-cost in vivo whole organism screening. In our recent screening of the distribution patterns of fluorescent compounds in live zebrafish larvae, fifteen compounds with tissue-specific distributions were identified. Several compounds were observed to accumulate in tissues where they were reported to induce side-effects, and compounds with similar structures tended to be enriched in the same tissues, with minor differences. In particular, we found three novel red fluorescent bone-staining dyes: purpurin, lucidin and 3-hydroxy-morindone; purpurin can effectively label bones in both larval and adult zebrafish, as well as in postnatal mice, without significantly affecting bone mass and density. Moreover, two structurally similar chemotherapeutic compounds, doxorubicin and epirubicin, were observed to have distinct distribution preferences in zebrafish. Epirubicin maintained a relatively higher concentration in the liver, and performed better in inhibiting hepatic hyperplasia caused by the over-expression of krasG12V. In total, our study suggests that the transparent zebrafish larvae serve as valuable tools for identifying tissue-specific distributions of fluorescent compounds.

  10. A Cell-Based Screen Reveals that the Albendazole Metabolite, Albendazole Sulfone, Targets Wolbachia

    Science.gov (United States)

    Bray, Walter M.; White, Pamela M.; Ruybal, Jordan; Lokey, R. Scott; Debec, Alain; Sullivan, William

    2012-01-01

    Wolbachia endosymbionts carried by filarial nematodes give rise to the neglected diseases African river blindness and lymphatic filariasis afflicting millions worldwide. Here we identify new Wolbachia-disrupting compounds by conducting high-throughput cell-based chemical screens using a Wolbachia-infected, fluorescently labeled Drosophila cell line. This screen yielded several Wolbachia-disrupting compounds including three that resembled Albendazole, a widely used anthelmintic drug that targets nematode microtubules. Follow-up studies demonstrate that a common Albendazole metabolite, Albendazole sulfone, reduces intracellular Wolbachia titer both in Drosophila melanogaster and Brugia malayi, the nematode responsible for lymphatic filariasis. Significantly, Albendazole sulfone does not disrupt Drosophila microtubule organization, suggesting that this compound reduces titer through direct targeting of Wolbachia. Accordingly, both DNA staining and FtsZ immunofluorescence demonstrates that Albendazole sulfone treatment induces Wolbachia elongation, a phenotype indicative of binary fission defects. This suggests that the efficacy of Albendazole in treating filarial nematode-based diseases is attributable to dual targeting of nematode microtubules and their Wolbachia endosymbionts. PMID:23028321

  11. Virtual screening using combinatorial cyclic peptide libraries reveals protein interfaces readily targetable by cyclic peptides.

    Science.gov (United States)

    Duffy, Fergal J; O'Donovan, Darragh; Devocelle, Marc; Moran, Niamh; O'Connell, David J; Shields, Denis C

    2015-03-23

    Protein-protein and protein-peptide interactions are responsible for the vast majority of biological functions in vivo, but targeting these interactions with small molecules has historically been difficult. What is required are efficient combined computational and experimental screening methods to choose among a number of potential protein interfaces worthy of targeting lead macrocyclic compounds for further investigation. To achieve this, we have generated combinatorial 3D virtual libraries of short disulfide-bonded peptides and compared them to pharmacophore models of important protein-protein and protein-peptide structures, including short linear motifs (SLiMs), protein-binding peptides, and turn structures at protein-protein interfaces, built from 3D models available in the Protein Data Bank. We prepared a total of 372 reference pharmacophores, which were matched against 108,659 multiconformer cyclic peptides. After normalization to exclude nonspecific cyclic peptides, the top hits notably are enriched for mimetics of turn structures, including a turn at the interaction surface of human α thrombin, and also feature several protein-binding peptides. The top cyclic peptide hits also cover the critical "hot spot" interaction sites predicted from the interaction crystal structure. We have validated our method by testing cyclic peptides predicted to inhibit thrombin, a key protein in the blood coagulation pathway of important therapeutic interest, identifying a cyclic peptide inhibitor with lead-like activity. We conclude that protein interfaces most readily targetable by cyclic peptides and related macrocyclic drugs may be identified computationally among a set of candidate interfaces, accelerating the choice of interfaces against which lead compounds may be screened.

  12. A case of pneumonia and sepsis in cirrhosis as paradigm of the problems in the management of bacterial infections in cirrhosis and of the limitations of current knowledge

    Directory of Open Access Journals (Sweden)

    Manuel Tufoni

    2013-09-01

    Full Text Available Bacterial infections are a major problem in the management of liver cirrhosis. They represent the first precipitating cause of death since patients with cirrhosis carry an increased risk of sepsis, sepsis-induced organ failure and death. Although the clinical presentation is often misleading, the presence of bacterial infection should always be actively searched and ruled out with certainty whenever a cirrhotic patient is admitted to the hospital with an acute clinical deterioration. Major changes in the epidemiology of bacterial infections have also occurred in the last decade making the choice of empirical antibiotic therapy a challenge. We report a paradigmatic case of a 54-year old man with hepatitis C-related cirrhosis admitted to the hospital for worsening of his ascites and onset of hepatic encephalopathy, an excellent example for the difficulties of management of sepsis in cirrhosis and the limits of current knowledge.

  13. White blood cell count, absolute neutrophil count, as predictors of hidden bacterial infections in febrile children 1-18 months of age without focus

    International Nuclear Information System (INIS)

    AL-Majali, R.M.

    2004-01-01

    Objectives: To study the relationship between White Blood Cell (WBC), Absolute Neutrophil Count (ANC) in febrile children 1-18 months of age as predictor of bacterial infection, so as to improve our predictability of bacterial infections in emergency room to decrease unnecessary admissions and antibiotic use. Methods: Retrospective review was performed on febrile patients 1-18 months of age that were admitted to hospital between August 2002 and March 2003 on the presumptive diagnosis of fever without focus, Complete septic work up was done for all patients according to local hospital protocol including Complete blood count (CBC), blood culture, urine culture, Chest X-Ray (CXR) and lumbar puncture, Patients who had history of antibiotics use within 48 hours of admission were excluded from the study, History, physical examination, laboratory and radiology data were reviewed. Data about the age, sex, temperature, presence or absence of focal bacterial infection, WBC, ANC, CXR report and body fluid culture results were collected and analyzed. Results: Thirty-four patients were reviewed in this study, Eight patients (23.5%) had bacterial infection: classified as group (2 patchy pneumonia, 3 Urinary tract infection (UTI), 2 meningitis, 1 Occult bacteremia (OB) and 26 patients (76.5%) had no evidence of bacterial infection, classified as group 2, No significant difference was found between the two groups in respect to age, sex, temperature and WBC P>0.05, while there was a significant difference between the two groups in respect to the ANC P = 0.02, also ANC had better sensitivity (78%) and specificity (89%) than WBC (sensitivity 77%, specificity 62%). Conclusion: ANC is a good predictive test for determining bacterial infection in young febrile children without focus, However there is need for other more reliable rapid cost effective measures in dealing with young febrile children at emergency department. (author)

  14. Combining chemical genomics screens in yeast to reveal spectrum of effects of chemical inhibition of sphingolipid biosynthesis

    Directory of Open Access Journals (Sweden)

    Giaever Guri

    2009-01-01

    Full Text Available Abstract Background Single genome-wide screens for the effect of altered gene dosage on drug sensitivity in the model organism Saccharomyces cerevisiae provide only a partial picture of the mechanism of action of a drug. Results Using the example of the tumor cell invasion inhibitor dihydromotuporamine C, we show that a more complete picture of drug action can be obtained by combining different chemical genomics approaches – analysis of the sensitivity of ρ0 cells lacking mitochondrial DNA, drug-induced haploinsufficiency, suppression of drug sensitivity by gene overexpression and chemical-genetic synthetic lethality screening using strains deleted of nonessential genes. Killing of yeast by this chemical requires a functional mitochondrial electron-transport chain and cytochrome c heme lyase function. However, we find that it does not require genes associated with programmed cell death in yeast. The chemical also inhibits endocytosis and intracellular vesicle trafficking and interferes with vacuolar acidification in yeast and in human cancer cells. These effects can all be ascribed to inhibition of sphingolipid biosynthesis by dihydromotuporamine C. Conclusion Despite their similar conceptual basis, namely altering drug sensitivity by modifying gene dosage, each of the screening approaches provided a distinct set of information that, when integrated, revealed a more complete picture of the mechanism of action of a drug on cells.

  15. High-throughput cell-based screening reveals a role for ZNF131 as a repressor of ERalpha signaling

    Directory of Open Access Journals (Sweden)

    Du Peige

    2008-10-01

    Full Text Available Abstract Background Estrogen receptor α (ERα is a transcription factor whose activity is affected by multiple regulatory cofactors. In an effort to identify the human genes involved in the regulation of ERα, we constructed a high-throughput, cell-based, functional screening platform by linking a response element (ERE with a reporter gene. This allowed the cellular activity of ERα, in cells cotransfected with the candidate gene, to be quantified in the presence or absence of its cognate ligand E2. Results From a library of 570 human cDNA clones, we identified zinc finger protein 131 (ZNF131 as a repressor of ERα mediated transactivation. ZNF131 is a typical member of the BTB/POZ family of transcription factors, and shows both ubiquitous expression and a high degree of sequence conservation. The luciferase reporter gene assay revealed that ZNF131 inhibits ligand-dependent transactivation by ERα in a dose-dependent manner. Electrophoretic mobility shift assay clearly demonstrated that the interaction between ZNF131 and ERα interrupts or prevents ERα binding to the estrogen response element (ERE. In addition, ZNF131 was able to suppress the expression of pS2, an ERα target gene. Conclusion We suggest that the functional screening platform we constructed can be applied for high-throughput genomic screening candidate ERα-related genes. This in turn may provide new insights into the underlying molecular mechanisms of ERα regulation in mammalian cells.

  16. Sonic Hedgehog Signaling Regulates Hematopoietic Stem/Progenitor Cell Activation during the Granulopoietic Response to Systemic Bacterial Infection.

    Science.gov (United States)

    Shi, Xin; Wei, Shengcai; Simms, Kevin J; Cumpston, Devan N; Ewing, Thomas J; Zhang, Ping

    2018-01-01

    Activation and reprogramming of hematopoietic stem/progenitor cells play a critical role in the granulopoietic response to bacterial infection. Our current study determined the significance of Sonic hedgehog (SHH) signaling in the regulation of hematopoietic precursor cell activity during the host defense response to systemic bacterial infection. Bacteremia was induced in male Balb/c mice via intravenous injection (i.v.) of Escherichia coli (5 × 10 7 CFUs/mouse). Control mice received i.v. saline. SHH protein level in bone marrow cell (BMC) lysates was markedly increased at both 24 and 48 h of bacteremia. By contrast, the amount of soluble SHH ligand in marrow elutes was significantly reduced. These contrasting alterations suggested that SHH ligand release from BMCs was reduced and/or binding of soluble SHH ligand to BMCs was enhanced. At both 12 and 24 h of bacteremia, SHH mRNA expression by BMCs was significantly upregulated. This upregulation of SHH mRNA expression was followed by a marked increase in SHH protein expression in BMCs. Activation of the ERK1/2-SP1 pathway was involved in mediating the upregulation of SHH gene expression. The major cell type showing the enhancement of SHH expression in the bone marrow was lineage positive cells. Gli1 positioned downstream of the SHH receptor activation serves as a key component of the hedgehog (HH) pathway. Primitive hematopoietic precursor cells exhibited the highest level of baseline Gli1 expression, suggesting that they were active cells responding to SHH ligand stimulation. Along with the increased expression of SHH in the bone marrow, expression of Gli1 by marrow cells was significantly upregulated at both mRNA and protein levels following bacteremia. This enhancement of Gli1 expression was correlated with activation of hematopoietic stem/progenitor cell proliferation. Mice with Gli1 gene deletion showed attenuation in activation of marrow hematopoietic stem/progenitor cell proliferation and inhibition

  17. Associations between intrauterine bacterial infection, reproductive tract inflammation, and reproductive performance in pasture-based dairy cows.

    Science.gov (United States)

    de Boer, Melvin; Buddle, Bryce M; Heuer, Cord; Hussein, Hassan; Zheng, Tao; LeBlanc, Stephen J; McDougall, Scott

    2015-06-01

    Reproductive tract bacterial infections, particularly those caused by Escherichia coli and Trueperella pyogenes, can have a negative impact on reproductive performance. It has been hypothesized that the presence of E coli early postpartum may increase the risk of isolation of T pyogenes later postpartum. The objective of the present study was to examine associations between intrauterine bacterial infections with E coli and T pyogenes and any bacterial growth (irrespective of bacterial species), purulent vaginal discharge (PVD), cytologic evidence of endometritis (an increased proportion of polymorphonuclear cells [PMNs]), and reproductive performance. Dairy cows (n = 272) from six herds were examined at Days 0 (median, 2 days in milk), 21 and 42 postpartum. From each cow two intrauterine samples were collected via triple-guarded cytobrush at Days 0 and 21. The first cytobrush was used for bacteriologic culture. Escherichia coli and T pyogenes were isolated by culture, and E coli isolates were assigned to one of four phylogenetic groups using a two-step triplex polymerase chain reaction. In addition, T pyogenes was confirmed by polymerase chain reaction. The second cytobrush was used to prepare a cytology slide. Nucleated cells (n = 200) were categorized as epithelial cells, PMNs, or macrophages. Cows were also assessed for body condition score, PVD score, the presence of a CL, and pregnancy. Statistical analysis was performed using multivariable models. There was no association between the presence of E coli at Day 0 and probability of isolation of T pyogenes 3 weeks later; however, E coli positive cows at Day 0 were more likely to be diagnosed with E coli at Day 21 (relative risk [RR] = 2.0, P bacterial growth at Day 21, irrespective of species, were less likely to conceive within 3 weeks after the start of the seasonal breeding program (RR = 0.8; P = 0.05). Interestingly, cows with 25% PMNs or greater at Day 0 had shorter time to pregnancy (hazard ratio = 1.32; P

  18. Pasteurization Procedures for Donor Human Milk Affect Body Growth, Intestinal Structure, and Resistance against Bacterial Infections in Preterm Pigs.

    Science.gov (United States)

    Li, Yanqi; Nguyen, Duc Ninh; de Waard, Marita; Christensen, Lars; Zhou, Ping; Jiang, Pingping; Sun, Jing; Bojesen, Anders Miki; Lauridsen, Charlotte; Lykkesfeldt, Jens; Dalsgaard, Trine Kastrup; Bering, Stine Brandt; Sangild, Per Torp

    2017-06-01

    Background: Holder pasteurization (HP) destroys multiple bioactive factors in donor human milk (DM), and UV-C irradiation (UVC) is potentially a gentler method for pasteurizing DM for preterm infants. Objective: We investigated whether UVC-treated DM improves gut maturation and resistance toward bacterial infections relative to HP-treated DM. Methods: Bacteria, selected bioactive components, and markers of antioxidant capacity were measured in unpasteurized donor milk (UP), HP-treated milk, and UVC-treated milk (all from the same DM pool). Fifty-seven cesarean-delivered preterm pigs (91% gestation; ratio of males to females, 30:27) received decreasing volumes of parental nutrition (average 69 mL · kg -1 · d -1 ) and increasing volumes of the 3 DM diets ( n = 19 each, average 89 mL · kg -1 · d -1 ) for 8-9 d. Body growth, gut structure and function, and systemic bacterial infection were evaluated. Results: A high bacterial load in the UP (6×10 5 colony forming units/mL) was eliminated similarly by HP and UVC treatments. Relative to HP-treated milk, both UVC-treated milk and UP showed greater activities of lipase and alkaline phosphatase and concentrations of lactoferrin, secretory immunoglobulin A, xanthine dehydrogenase, and some antioxidant markers (all P < 0.05). The pigs fed UVC-treated milk and pigs fed UP showed higher relative weight gain than pigs fed HP-treated milk (5.4% and 3.5%), and fewer pigs fed UVC-treated milk had positive bacterial cultures in the bone marrow (28%) than pigs fed HP-treated milk (68%) ( P < 0.05). Intestinal health was also improved in pigs fed UVC-treated milk compared with those fed HP-treated milk as indicated by a higher plasma citrulline concentration (36%) and villus height (38%) ( P < 0.05) and a tendency for higher aminopeptidase N (48%) and claudin-4 (26%) concentrations in the distal intestine ( P < 0.08). The gut microbiota composition was similar among groups except for greater proportions of Enterococcus in pigs

  19. Screening Bioactives Reveals Nanchangmycin as a Broad Spectrum Antiviral Active against Zika Virus

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    Keiko Rausch

    2017-01-01

    Full Text Available Zika virus is an emerging arthropod-borne flavivirus for which there are no vaccines or specific therapeutics. We screened a library of 2,000 bioactive compounds for their ability to block Zika virus infection in three distinct cell types with two different strains of Zika virus. Using a microscopy-based assay, we validated 38 drugs that inhibited Zika virus infection, including FDA-approved nucleoside analogs. Cells expressing high levels of the attachment factor AXL can be protected from infection with receptor tyrosine kinase inhibitors, while placental-derived cells that lack AXL expression are insensitive to this inhibition. Importantly, we identified nanchangmycin as a potent inhibitor of Zika virus entry across all cell types tested, including physiologically relevant primary cells. Nanchangmycin also was active against other medically relevant viruses, including West Nile, dengue, and chikungunya viruses that use a similar route of entry. This study provides a resource of small molecules to study Zika virus pathogenesis.

  20. An overexpression screen of Toxoplasma gondii Rab-GTPases reveals distinct transport routes to the micronemes.

    Directory of Open Access Journals (Sweden)

    Katrin Kremer

    2013-03-01

    Full Text Available The basic organisation of the endomembrane system is conserved in all eukaryotes and comparative genome analyses provides compelling evidence that the endomembrane system of the last common eukaryotic ancestor (LCEA is complex with many genes required for regulated traffic being present. Although apicomplexan parasites, causative agents of severe human and animal diseases, appear to have only a basic set of trafficking factors such as Rab-GTPases, they evolved unique secretory organelles (micronemes, rhoptries and dense granules that are sequentially secreted during invasion of the host cell. In order to define the secretory pathway of apicomplexans, we performed an overexpression screen of Rabs in Toxoplasma gondii and identified Rab5A and Rab5C as important regulators of traffic to micronemes and rhoptries. Intriguingly, we found that not all microneme proteins traffic depends on functional Rab5A and Rab5C, indicating the existence of redundant microneme targeting pathways. Using two-colour super-resolution stimulated emission depletion (STED we verified distinct localisations of independent microneme proteins and demonstrate that micronemal organelles are organised in distinct subsets or subcompartments. Our results suggest that apicomplexan parasites modify classical regulators of the endocytic system to carryout essential parasite-specific roles in the biogenesis of their unique secretory organelles.

  1. Population Screening Using Sewage Reveals Pan-Resistant Bacteria in Hospital and Community Samples.

    Science.gov (United States)

    Meir-Gruber, Lital; Manor, Yossi; Gefen-Halevi, Shiraz; Hindiyeh, Musa Y; Mileguir, Fernando; Azar, Roberto; Smollan, Gill; Belausov, Natasha; Rahav, Galia; Shamiss, Ari; Mendelson, Ella; Keller, Nathan

    2016-01-01

    The presence of pan-resistant bacteria worldwide possesses a threat to global health. It is difficult to evaluate the extent of carriage of resistant bacteria in the population. Sewage sampling is a possible way to monitor populations. We evaluated the presence of pan-resistant bacteria in Israeli sewage collected from all over Israel, by modifying the pour plate method for heterotrophic plate count technique using commercial selective agar plates. This method enables convenient and fast sewage sampling and detection. We found that sewage in Israel contains multiple pan-resistant bacteria including carbapenemase resistant Enterobacteriacae carrying blaKPC and blaNDM-1, MRSA and VRE. blaKPC carrying Klebsiella pneumonia and Enterobacter cloacae were the most common Enterobacteriacae drug resistant bacteria found in the sewage locations we sampled. Klebsiella pneumonia, Enterobacter spp., Escherichia coli and Citrobacter spp. were the 4 main CRE isolated from Israeli sewage and also from clinical samples in our clinical microbiology laboratory. Hospitals and Community sewage had similar percentage of positive samplings for blaKPC and blaNDM-1. VRE was found to be more abundant in sewage in Israel than MRSA but there were more locations positive for MRSA and VRE bacteria in Hospital sewage than in the Community. Therefore, our upgrade of the pour plate method for heterotrophic plate count technique using commercial selective agar plates can be a useful tool for routine screening and monitoring of the population for pan-resistant bacteria using sewage.

  2. Genome-wide RNAi screen reveals ALK1 mediates LDL uptake and transcytosis in endothelial cells

    Science.gov (United States)

    Kraehling, Jan R.; Chidlow, John H.; Rajagopal, Chitra; Sugiyama, Michael G.; Fowler, Joseph W.; Lee, Monica Y.; Zhang, Xinbo; Ramírez, Cristina M.; Park, Eon Joo; Tao, Bo; Chen, Keyang; Kuruvilla, Leena; Larriveé, Bruno; Folta-Stogniew, Ewa; Ola, Roxana; Rotllan, Noemi; Zhou, Wenping; Nagle, Michael W.; Herz, Joachim; Williams, Kevin Jon; Eichmann, Anne; Lee, Warren L.; Fernández-Hernando, Carlos; Sessa, William C.

    2016-01-01

    In humans and animals lacking functional LDL receptor (LDLR), LDL from plasma still readily traverses the endothelium. To identify the pathways of LDL uptake, a genome-wide RNAi screen was performed in endothelial cells and cross-referenced with GWAS-data sets. Here we show that the activin-like kinase 1 (ALK1) mediates LDL uptake into endothelial cells. ALK1 binds LDL with lower affinity than LDLR and saturates only at hypercholesterolemic concentrations. ALK1 mediates uptake of LDL into endothelial cells via an unusual endocytic pathway that diverts the ligand from lysosomal degradation and promotes LDL transcytosis. The endothelium-specific genetic ablation of Alk1 in Ldlr-KO animals leads to less LDL uptake into the aortic endothelium, showing its physiological role in endothelial lipoprotein metabolism. In summary, identification of pathways mediating LDLR-independent uptake of LDL may provide unique opportunities to block the initiation of LDL accumulation in the vessel wall or augment hepatic LDLR-dependent clearance of LDL. PMID:27869117

  3. Three-cohort targeted gene screening reveals a non-synonymous TRKA polymorphism associated with schizophrenia

    DEFF Research Database (Denmark)

    van Schijndel, Jessica E; van Loo, Karen M J; van Zweeden, Martine

    2009-01-01

    selected non-synonymous single-nucleotide polymorphisms (SNPs) in three independent Caucasian schizophrenia case-control cohorts (USA, Denmark and Norway). A meta-analysis revealed ten non-synonymous SNPs that were nominally associated with schizophrenia, nine of which have not been previously linked...... attractive candidate for further study concerns SNP rs6336 (q=0.12) that causes the substitution of an evolutionarily highly conserved amino acid residue in the kinase domain of the neurodevelopmentally important receptor TRKA. Thus, TRKA signaling may represent a novel susceptibility pathway...

  4. Functional genomic screening reveals asparagine dependence as a metabolic vulnerability in sarcoma

    OpenAIRE

    Hettmer, Simone; Schinzel, Anna C; Tchessalova, Daria; Schneider, Michaela; Parker, Christina L; Bronson, Roderick T; Richards, Nigel GJ; Hahn, William C; Wagers, Amy J

    2015-01-01

    eLife digest Sarcoma is a type of cancer that forms in the connective tissues of the body, such as bone, cartilage, muscle and fat. Usually, treatment involves surgical removal of the tumor and/or radiation to kill the tumor cells. However, if sarcomas spread to other parts of the body, the treatment options are limited. Genetic studies have revealed several genetic changes that contribute to the formation of sarcomas. Many sarcomas have a mutation in a gene that encodes a protein called Ras....

  5. Screening of a long-term sample set reveals two Ranavirus lineages in British herpetofauna.

    Directory of Open Access Journals (Sweden)

    Stephen J Price

    Full Text Available Reports of severe disease outbreaks in amphibian communities in mainland Europe due to strains of the common midwife toad virus (CMTV-like clade of Ranavirus are increasing and have created concern due to their considerable population impacts. In Great Britain, viruses in another clade of Ranavirus-frog virus 3 (FV3-like-have caused marked declines of common frog (Rana temporaria populations following likely recent virus introductions. The British public has been reporting mortality incidents to a citizen science project since 1992, with carcasses submitted for post-mortem examination, resulting in a long-term tissue archive spanning 25 years. We screened this archive for ranavirus (458 individuals from 228 incidents using molecular methods and undertook preliminary genotyping of the ranaviruses detected. In total, ranavirus was detected in 90 individuals from 41 incidents focused in the north and south of England. The majority of detections involved common frogs (90% but also another anuran, a caudate and a reptile. Most incidents were associated with FV3-like viruses but two, separated by 300 km and 16 years, involved CMTV-like viruses. These British CMTV-like viruses were more closely related to ranaviruses from mainland Europe than to each other and were estimated to have diverged at least 458 years ago. This evidence of a CMTV-like virus in Great Britain in 1995 represents the earliest confirmed case of a CMTV associated with amphibians and raises important questions about the history of ranavirus in Great Britain and the epidemiology of CMTV-like viruses. Despite biases present in the opportunistic sample used, this study also demonstrates the role of citizen science projects in generating resources for research and the value of maintaining long-term wildlife tissue archives.

  6. Comparative usefulness of inflammatory markers to indicate bacterial infection-analyzed according to blood culture results and related clinical factors.

    Science.gov (United States)

    Nishikawa, Hirokazu; Shirano, Michinori; Kasamatsu, Yu; Morimura, Ayumi; Iida, Ko; Kishi, Tomomi; Goto, Tetsushi; Okamoto, Saki; Ehara, Eiji

    2016-01-01

    To assess relationships of inflammatory markers and 2 related clinical factors with blood culture results, we retrospectively investigated inpatients' blood culture and blood chemistry findings that were recorded from January to December 2014 using electronic medical records and analyzed the data of 852 subjects (426 culture-positive and 426 culture-negative). Results suggested that the risk of positive blood culture statistically increased as inflammatory marker levels and the number of related factors increased. Concerning the effectiveness of inflammatory markers, when the outcome definition was also changed for C-reactive protein (CRP), the odds ratio had a similar value, whereas when the outcome definition of blood culture positivity was used for procalcitonin (PCT), the greatest effectiveness of that was detected. Therefore, the current results suggest that PCT is more useful than CRP as an auxiliary indication of bacterial infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Shrimp TAB1 interacts with TAK1 and p38 and activates the host innate immune response to bacterial infection.

    Science.gov (United States)

    Wang, Sheng; Li, Mengqiao; Yin, Bin; Li, Haoyang; Xiao, Bang; Lǚ, Kai; Huang, Zhijian; Li, Sedong; He, Jianguo; Li, Chaozheng

    2017-08-01

    Mammalian TAB1 has been previously identified as transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) binding protein, which functions as the activator of TAK1 and p38. This report, for the first time, identified and characterized the homolog of TAB1 in shrimp, to be specific, the homolog gene from Litopenaeus vannamei, containing a 1560-bp open reading frame (ORF) that encoded a putative protein of 519 amino acids with the conserved PP2Cc (Serine/threonine phosphatases, family 2C, catalytic) domain in N-terminal and a TAK1 binding motif in C-terminus, has been cloned and named LvTAB1. LvTAB1 was most abundant in gills and its expression could respond significantly to a series of stimuli, including LPS, Vibrio parahemolyticus and Staphylococcus aureus. Moreover, Co-immunoprecipitation (Co-IP) experiments showed that LvTAB1 could combine with LvTAK1 as well as Lvp38, two members of IMD-NF-κB/MAPK pathway, which meant LvTAB1 could have a role in regulating the activities of these kinases. Over-expression of LvTAB1 in drosophila S2 cells could improve the transcriptional levels of antimicrobial peptide genes (AMPs) such as Diptericin (Dpt), the hallmark of drosophila NF-κB activated genes, indicating its activation effect on NF-κB pathway. Furthermore, suppression of LvTAB1 expression in vivo by RNA-interference increased the sensibility of shrimps to V. parahaemolyticus infection, implying its protective role against bacterial infection. In conclusion, these results provide some insight into the function of LvTAB1 during bacterial infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Screen for chemical modulators of autophagy reveals novel therapeutic inhibitors of mTORC1 signaling.

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    Aruna D Balgi

    Full Text Available BACKGROUND: Mammalian target of rapamycin complex 1 (mTORC1 is a protein kinase that relays nutrient availability signals to control numerous cellular functions including autophagy, a process of cellular self-eating activated by nutrient depletion. Addressing the therapeutic potential of modulating mTORC1 signaling and autophagy in human disease requires active chemicals with pharmacologically desirable properties. METHODOLOGY/PRINCIPAL FINDINGS: Using an automated cell-based assay, we screened a collection of >3,500 chemicals and identified three approved drugs (perhexiline, niclosamide, amiodarone and one pharmacological reagent (rottlerin capable of rapidly increasing autophagosome content. Biochemical assays showed that the four compounds stimulate autophagy and inhibit mTORC1 signaling in cells maintained in nutrient-rich conditions. The compounds did not inhibit mTORC2, which also contains mTOR as a catalytic subunit, suggesting that they do not inhibit mTOR catalytic activity but rather inhibit signaling to mTORC1. mTORC1 inhibition and autophagosome accumulation induced by perhexiline, niclosamide or rottlerin were rapidly reversed upon drug withdrawal whereas amiodarone inhibited mTORC1 essentially irreversibly. TSC2, a negative regulator of mTORC1, was required for inhibition of mTORC1 signaling by rottlerin but not for mTORC1 inhibition by perhexiline, niclosamide and amiodarone. Transient exposure of immortalized mouse embryo fibroblasts to these drugs was not toxic in nutrient-rich conditions but led to rapid cell death by apoptosis in starvation conditions, by a mechanism determined in large part by the tuberous sclerosis complex protein TSC2, an upstream regulator of mTORC1. By contrast, transient exposure to the mTORC1 inhibitor rapamycin caused essentially irreversible mTORC1 inhibition, sustained inhibition of cell growth and no selective cell killing in starvation. CONCLUSION/SIGNIFICANCE: The observation that drugs already

  9. RNAi screen reveals host cell kinases specifically involved in Listeria monocytogenes spread from cell to cell.

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    Ryan Chong

    Full Text Available Intracellular bacterial pathogens, such as Listeria monocytogenes and Rickettsia conorii display actin-based motility in the cytosol of infected cells and spread from cell to cell through the formation of membrane protrusions at the cell cortex. Whereas the mechanisms supporting cytosolic actin-based motility are fairly well understood, it is unclear whether specific host factors may be required for supporting the formation and resolution of membrane protrusions. To address this gap in knowledge, we have developed high-throughput fluorescence microscopy and computer-assisted image analysis procedures to quantify pathogen spread in human epithelial cells. We used the approach to screen a siRNA library covering the human kinome and identified 7 candidate kinases whose depletion led to severe spreading defects in cells infected with L. monocytogenes. We conducted systematic validation procedures with redundant silencing reagents and confirmed the involvement of the serine/threonine kinases, CSNK1A1 and CSNK2B. We conducted secondary assays showing that, in contrast with the situation observed in CSNK2B-depleted cells, L. monocytogenes formed wild-type cytosolic tails and displayed wild-type actin-based motility in the cytosol of CSNK1A1-depleted cells. Furthermore, we developed a protrusion formation assay and showed that the spreading defect observed in CSNK1A1-depleted cells correlated with the formation of protrusion that did not resolve into double-membrane vacuoles. Moreover, we developed sending and receiving cell-specific RNAi procedures and showed that CSNK1A was required in the sending cells, but was dispensable in the receiving cells, for protrusion resolution. Finally, we showed that the observed defects were specific to Listeria monocytogenes, as Rickettsia conorii displayed wild-type cell-to-cell spread in CSNK1A1- and CSNK2B-depleted cells. We conclude that, in addition to the specific host factors supporting cytosolic actin

  10. Protection of honeybee Apis mellifera by its endogenous and exogenous lactic flora against bacterial infections

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    Irakli Janashia

    2016-09-01

    Three exogenous bacteriocin-producing LAB strains were tested against the same pathogens and against 25 endogenous bacterial isolates representing 11 different LAB species. The screening showed that all the tested exogenous bacteriocin-producing strains inhibited the tested P. larvae strains. The endogenous LAB strains exhibited varied sensitivity profiles when treated with bacteriocin-producing strains. This raises similar challenges to those observed in antibiotic applications leading to dysbacteriosis, even though the efficacy of these bacteriocins against P. larvae in an in vitro system is evident.

  11. Fluoride exposure abates pro-inflammatory response and induces in vivo apoptosis rendering zebrafish (Danio rerio) susceptible to bacterial infections.

    Science.gov (United States)

    Singh, Rashmi; Khatri, Preeti; Srivastava, Nidhi; Jain, Shruti; Brahmachari, Vani; Mukhopadhyay, Asish; Mazumder, Shibnath

    2017-04-01

    The present study describes the immunotoxic effect of chronic fluoride exposure on adult zebrafish (Danio rerio). Zebrafish were exposed to fluoride (71.12 mg/L; 1/10 LC 50 ) for 30 d and the expression of selected genes studied. We observed significant elevation in the detoxification pathway gene cyp1a suggesting chronic exposure to non-lethal concentration of fluoride is indeed toxic to fish. Fluoride mediated pro-oxidative stress is implicated with the downregulation in superoxide dismutase 1 and 2 (sod1/2) genes. Fluoride affected DNA repair machinery by abrogating the expression of the DNA repair gene rad51 and growth arrest and DNA damage inducible beta a gene gadd45ba. The upregulated expression of casp3a coupled with altered Bcl-2 associated X protein/B-cell lymphoma 2 ratio (baxa/bcl2a) clearly suggested chronic fluoride exposure induced the apoptotic cascade in zebrafish. Fluoride-exposed zebrafish when challenged with non-lethal dose of fish pathogen A. hydrophila revealed gross histopathology in spleen, bacterial persistence and significant mortality. We report that fluoride interferes with system-level output of pro-inflammatory cytokines tumour necrosis factor-α, interleukin-1β and interferon-γ, as a consequence, bacteria replicate efficiently causing significant fish mortality. We conclude, chronic fluoride exposure impairs the redox balance, affects DNA repair machinery with pro-apoptotic implications and suppresses pro-inflammatory cytokines expression abrogating host immunity to bacterial infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. The diagnostic value of CRP, IL-8, PCT, and sTREM-1 in the detection of bacterial infections in pediatric oncology patients with febrile neutropenia

    NARCIS (Netherlands)

    Miedema, Karin G. E.; de Bont, Eveline S. J. M.; Elferink, Rob F. M. Oude; van Vliet, Michel J.; Nijhuis, Claudi S. M. Oude; Kamps, Willem A.; Tissing, Wim J. E.

    2011-01-01

    In this study, we evaluated C-reactive protein (CRP), interleukin (IL)-8, procalcitonin (PCT), and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) as predictors for bacterial infection in febrile neutropenia, plus their usefulness in febrile neutropenia during chemotherapy-induced

  13. Signature-tagged mutagenesis screening revealed a novel smooth-to-rough transition determinant of Salmonella enterica serovar Enteritidis.

    Science.gov (United States)

    Jiao, Yang; Guo, Rongxian; Tang, Peipei; Kang, Xilong; Yin, Junlei; Wu, Kaiyue; Geng, Shizhong; Li, Qiuchun; Sun, Jun; Xu, Xiulong; Zhou, Xiaohui; Gan, Junji; Jiao, Xinan; Liu, Xiufan; Pan, Zhiming

    2017-03-03

    Salmonella enterica serovar Enteritidis (S. Enteritidis) has emerged as one of the most important food-borne pathogens for humans. Lipopolysaccharide (LPS), as a component of the outer membrane, is responsible for the virulence and smooth-to-rough transition in S. Enteritidis. In this study, we screened S. Enteritidis signature-tagged transposon mutant library using monoclonal antibody against somatic O 9 antigen (O 9 MAb) and O 9 factor rabbit antiserum to identify novel genes that are involved in smooth-to-rough transition. A total of 480 mutants were screened and one mutant with transposon insertion in rfbG gene had smooth-to-rough transition phenotype. In order to verify the role of rfbG gene, an rfbG insertion or deletion mutant was constructed using λ-Red recombination system. Phenotypic and biological analysis revealed that rfbG insertion or deletion mutants were similar to the wild-type strain in growth rate and biochemical properties, but the swimming motility was reduced. SE Slide Agglutination test and ELISA test showed that rfbG mutants do not stimulate animals to produce agglutinating antibody. In addition, the half-lethal dose (LD 50 ) of the rfbG deletion mutant strain was 10 6.6 -fold higher than that of the parent strain in a mouse model when injected intraperitoneally. These data indicate that the rfbG gene is involved in smooth-to-rough transition, swimming motility and virulence of S. Enteritidis. Furthermore, somatic O-antigen antibody-based approach to screen signature-tagged transposon mutants is feasible to clarify LPS biosynthesis and to find suitable markers in DIVA-vaccine research.

  14. Quantitative genome-wide genetic interaction screens reveal global epistatic relationships of protein complexes in Escherichia coli.

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    Mohan Babu

    2014-02-01

    Full Text Available Large-scale proteomic analyses in Escherichia coli have documented the composition and physical relationships of multiprotein complexes, but not their functional organization into biological pathways and processes. Conversely, genetic interaction (GI screens can provide insights into the biological role(s of individual gene and higher order associations. Combining the information from both approaches should elucidate how complexes and pathways intersect functionally at a systems level. However, such integrative analysis has been hindered due to the lack of relevant GI data. Here we present a systematic, unbiased, and quantitative synthetic genetic array screen in E. coli describing the genetic dependencies and functional cross-talk among over 600,000 digenic mutant combinations. Combining this epistasis information with putative functional modules derived from previous proteomic data and genomic context-based methods revealed unexpected associations, including new components required for the biogenesis of iron-sulphur and ribosome integrity, and the interplay between molecular chaperones and proteases. We find that functionally-linked genes co-conserved among γ-proteobacteria are far more likely to have correlated GI profiles than genes with divergent patterns of evolution. Overall, examining bacterial GIs in the context of protein complexes provides avenues for a deeper mechanistic understanding of core microbial systems.

  15. Systematic screen for mutants resistant to TORC1 inhibition in fission yeast reveals genes involved in cellular ageing and growth

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    Charalampos Rallis

    2014-01-01

    Target of rapamycin complex 1 (TORC1, which controls growth in response to nutrients, promotes ageing in multiple organisms. The fission yeast Schizosaccharomyces pombe emerges as a valuable genetic model system to study TORC1 function and cellular ageing. Here we exploited the combinatorial action of rapamycin and caffeine, which inhibit fission yeast growth in a TORC1-dependent manner. We screened a deletion library, comprising ∼84% of all non-essential fission yeast genes, for drug-resistant mutants. This screen identified 33 genes encoding functions such as transcription, kinases, mitochondrial respiration, biosynthesis, intra-cellular trafficking, and stress response. Among the corresponding mutants, 5 showed shortened and 21 showed increased maximal chronological lifespans; 15 of the latter mutants showed no further lifespan increase with rapamycin and might thus represent key targets downstream of TORC1. We pursued the long-lived sck2 mutant with additional functional analyses, revealing that the Sck2p kinase functions within the TORC1 network and is required for normal cell growth, global protein translation, and ribosomal S6 protein phosphorylation in a nutrient-dependent manner. Notably, slow cell growth was associated with all long-lived mutants while oxidative-stress resistance was not.

  16. In Vivo Screening Using Transgenic Zebrafish Embryos Reveals New Effects of HDAC Inhibitors Trichostatin A and Valproic Acid on Organogenesis.

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    Ling Li

    Full Text Available The effects of endocrine disrupting chemicals (EDCs on reproduction are well known, whereas their developmental effects are much less characterized. However, exposure to endocrine disruptors during organogenesis may lead to deleterious and permanent problems later in life. Zebrafish (Danio rerio transgenic lines expressing the green fluorescent protein (GFP in specific organs and tissues are powerful tools to uncover developmental defects elicited by EDCs. Here, we used seven transgenic lines to visualize in vivo whether a series of EDCs and other pharmaceutical compounds can alter organogenesis in zebrafish. We used transgenic lines expressing GFP in pancreas, liver, blood vessels, inner ear, nervous system, pharyngeal tooth and pectoral fins. This screen revealed that four of the tested chemicals have detectable effects on different organs, which shows that the range of effects elicited by EDCs is wider than anticipated. The endocrine disruptor tetrabromobisphenol-A (TBBPA, as well as the three drugs diclofenac, trichostatin A (TSA and valproic acid (VPA induced abnormalities in the embryonic vascular system of zebrafish. Moreover, TSA and VPA induced specific alterations during the development of pancreas, an observation that was confirmed by in situ hybridization with specific markers. Developmental delays were also induced by TSA and VPA in the liver and in pharyngeal teeth, resulting in smaller organ size. Our results show that EDCs can induce a large range of developmental alterations during embryogenesis of zebrafish and establish GFP transgenic lines as powerful tools to screen for EDCs effects in vivo.

  17. Effect of immediate initiation of antiretroviral therapy on risk of severe bacterial infections in HIV-positive people with CD4 cell counts of more than 500 cells per μL

    DEFF Research Database (Denmark)

    O'Connor, Jemma; Vjecha, Michael J; Phillips, Andrew N

    2017-01-01

    BACKGROUND: The effects of antiretroviral therapy on risk of severe bacterial infections in people with high CD4 cell counts have not been well described. In this study, we aimed to quantify the effects of immediate versus deferred ART on the risk of severe bacterial infection in people with high...... μL. We used Cox proportional hazards regression to model time to severe bacterial infection, which was defined as a composite endpoint of bacterial pneumonia (confirmed by the endpoint review committee), pulmonary or extrapulmonary tuberculosis, or any bacterial infectious disorder of grade 4...... had severe bacterial infections (immediate-initiation group n=34, deferred-initiation group n=86; median 2·8 years of follow-up). Immediate ART was associated with a reduced risk of severe bacterial infection compared with deferred ART (hazard ratio [HR] 0·39, 95% CI 0·26-0·57, p

  18. A genetic screen for vascular mutants in zebrafish reveals dynamic roles for Vegf/Plcg1 signaling during artery development.

    Science.gov (United States)

    Covassin, L D; Siekmann, A F; Kacergis, M C; Laver, E; Moore, J C; Villefranc, J A; Weinstein, B M; Lawson, N D

    2009-05-15

    In this work we describe a forward genetic approach to identify mutations that affect blood vessel development in the zebrafish. By applying a haploid screening strategy in a transgenic background that allows direct visualization of blood vessels, it was possible to identify several classes of mutant vascular phenotypes. Subsequent characterization of mutant lines revealed that defects in Vascular endothelial growth factor (Vegf) signaling specifically affected artery development. Comparison of phenotypes associated with different mutations within a functional zebrafish Vegf receptor-2 ortholog (referred to as kdr-like, kdrl) revealed surprisingly varied effects on vascular development. In parallel, we identified an allelic series of mutations in phospholipase c gamma 1 (plcg1). Together with in vivo structure-function analysis, our results suggest a requirement for Plcg1 catalytic activity downstream of receptor tyrosine kinases. We further find that embryos lacking both maternal and zygotic plcg1 display more severe defects in artery differentiation but are otherwise similar to zygotic mutants. Finally, we demonstrate through mosaic analysis that plcg1 functions autonomously in endothelial cells. Together our genetic analyses suggest that Vegf/Plcg1 signaling acts at multiple time points and in different signaling contexts to mediate distinct aspects of artery development.

  19. Bacterial Infections across the Ants: Frequency and Prevalence of Wolbachia, Spiroplasma, and Asaia

    Directory of Open Access Journals (Sweden)

    Stefanie Kautz

    2013-01-01

    Full Text Available Bacterial endosymbionts are common across insects, but we often lack a deeper knowledge of their prevalence across most organisms. Next-generation sequencing approaches can characterize bacterial diversity associated with a host and at the same time facilitate the fast and simultaneous screening of infectious bacteria. In this study, we used 16S rRNA tag encoded amplicon pyrosequencing to survey bacterial communities of 310 samples representing 221 individuals, 176 colonies and 95 species of ants. We found three distinct endosymbiont groups—Wolbachia (Alphaproteobacteria: Rickettsiales, Spiroplasma (Firmicutes: Entomoplasmatales, and relatives of Asaia (Alphaproteobacteria: Rhodospirillales—at different infection frequencies (at the ant species level: 22.1%, 28.4%, and 14.7%, resp. and relative abundances within bacterial communities (1.0%–99.9%. Spiroplasma was particularly enriched in the ant genus Polyrhachis, while Asaia relatives were most prevalent in arboreal ants of the genus Pseudomyrmex. While Wolbachia and Spiroplasma have been surveyed in ants before, Asaia, an acetic acid bacterium capable of fixing atmospheric nitrogen, has received much less attention. Due to sporadic prevalence across all ant taxa investigated, we hypothesize facultative associations for all three bacterial genera. Infection patterns are discussed in relation to potential adaptation of specific bacteria in certain ant groups.

  20. Curative Treatment of Severe Gram-Negative Bacterial Infections by a New Class of Antibiotics Targeting LpxC.

    Science.gov (United States)

    Lemaître, Nadine; Liang, Xiaofei; Najeeb, Javaria; Lee, Chul-Jin; Titecat, Marie; Leteurtre, Emmanuelle; Simonet, Michel; Toone, Eric J; Zhou, Pei; Sebbane, Florent

    2017-07-25

    The infectious diseases caused by multidrug-resistant bacteria pose serious threats to humankind. It has been suggested that an antibiotic targeting LpxC of the lipid A biosynthetic pathway in Gram-negative bacteria is a promising strategy for curing Gram-negative bacterial infections. However, experimental proof of this concept is lacking. Here, we describe our discovery and characterization of a biphenylacetylene-based inhibitor of LpxC, an essential enzyme in the biosynthesis of the lipid A component of the outer membrane of Gram-negative bacteria. The compound LPC-069 has no known adverse effects in mice and is effective in vitro against a broad panel of Gram-negative clinical isolates, including several multiresistant and extremely drug-resistant strains involved in nosocomial infections. Furthermore, LPC-069 is curative in a murine model of one of the most severe human diseases, bubonic plague, which is caused by the Gram-negative bacterium Yersinia pestis Our results demonstrate the safety and efficacy of LpxC inhibitors as a new class of antibiotic against fatal infections caused by extremely virulent pathogens. The present findings also highlight the potential of LpxC inhibitors for clinical development as therapeutics for infections caused by multidrug-resistant bacteria. IMPORTANCE The rapid spread of antimicrobial resistance among Gram-negative bacilli highlights the urgent need for new antibiotics. Here, we describe a new class of antibiotics lacking cross-resistance with conventional antibiotics. The compounds inhibit LpxC, a key enzyme in the lipid A biosynthetic pathway in Gram-negative bacteria, and are active in vitro against a broad panel of clinical isolates of Gram-negative bacilli involved in nosocomial and community infections. The present study also constitutes the first demonstration of the curative treatment of bubonic plague by a novel, broad-spectrum antibiotic targeting LpxC. Hence, the data highlight the therapeutic potential of Lpx

  1. Curative Treatment of Severe Gram-Negative Bacterial Infections by a New Class of Antibiotics Targeting LpxC

    Energy Technology Data Exchange (ETDEWEB)

    Lemaître, Nadine; Liang, Xiaofei; Najeeb, Javaria; Lee, Chul-Jin; Titecat, Marie; Leteurtre, Emmanuelle; Simonet, Michel; Toone, Eric J.; Zhou, Pei; Sebbane, Florent; Nacy, Carol A.

    2017-07-25

    ABSTRACT

    The infectious diseases caused by multidrug-resistant bacteria pose serious threats to humankind. It has been suggested that an antibiotic targeting LpxC of the lipid A biosynthetic pathway in Gram-negative bacteria is a promising strategy for curing Gram-negative bacterial infections. However, experimental proof of this concept is lacking. Here, we describe our discovery and characterization of a biphenylacetylene-based inhibitor of LpxC, an essential enzyme in the biosynthesis of the lipid A component of the outer membrane of Gram-negative bacteria. The compound LPC-069 has no known adverse effects in mice and is effectivein vitroagainst a broad panel of Gram-negative clinical isolates, including several multiresistant and extremely drug-resistant strains involved in nosocomial infections. Furthermore, LPC-069 is curative in a murine model of one of the most severe human diseases, bubonic plague, which is caused by the Gram-negative bacteriumYersinia pestis. Our results demonstrate the safety and efficacy of LpxC inhibitors as a new class of antibiotic against fatal infections caused by extremely virulent pathogens. The present findings also highlight the potential of LpxC inhibitors for clinical development as therapeutics for infections caused by multidrug-resistant bacteria.

    IMPORTANCEThe rapid spread of antimicrobial resistance among Gram-negative bacilli highlights the urgent need for new antibiotics. Here, we describe a new class of antibiotics lacking cross-resistance with conventional antibiotics. The compounds inhibit LpxC, a key enzyme in the lipid A biosynthetic pathway in Gram-negative bacteria, and are activein vitroagainst a broad panel of clinical isolates of Gram-negative bacilli involved in nosocomial and community infections. The present study also constitutes the first demonstration of the curative treatment of bubonic plague by a novel, broad

  2. A functional screen reveals an extensive layer of transcriptional and splicing control underlying RAS/MAPK signaling in Drosophila.

    Directory of Open Access Journals (Sweden)

    Dariel Ashton-Beaucage

    2014-03-01

    Full Text Available The small GTPase RAS is among the most prevalent oncogenes. The evolutionarily conserved RAF-MEK-MAPK module that lies downstream of RAS is one of the main conduits through which RAS transmits proliferative signals in normal and cancer cells. Genetic and biochemical studies conducted over the last two decades uncovered a small set of factors regulating RAS/MAPK signaling. Interestingly, most of these were found to control RAF activation, thus suggesting a central regulatory role for this event. Whether additional factors are required at this level or further downstream remains an open question. To obtain a comprehensive view of the elements functionally linked to the RAS/MAPK cascade, we used a quantitative assay in Drosophila S2 cells to conduct a genome-wide RNAi screen for factors impacting RAS-mediated MAPK activation. The screen led to the identification of 101 validated hits, including most of the previously known factors associated to this pathway. Epistasis experiments were then carried out on individual candidates to determine their position relative to core pathway components. While this revealed several new factors acting at different steps along the pathway--including a new protein complex modulating RAF activation--we found that most hits unexpectedly work downstream of MEK and specifically influence MAPK expression. These hits mainly consist of constitutive splicing factors and thereby suggest that splicing plays a specific role in establishing MAPK levels. We further characterized two representative members of this group and surprisingly found that they act by regulating mapk alternative splicing. This study provides an unprecedented assessment of the factors modulating RAS/MAPK signaling in Drosophila. In addition, it suggests that pathway output does not solely rely on classical signaling events, such as those controlling RAF activation, but also on the regulation of MAPK levels. Finally, it indicates that core splicing

  3. Structural motif screening reveals a novel, conserved carbohydrate-binding surface in the pathogenesis-related protein PR-5d

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    Moffatt Barbara A

    2010-08-01

    Full Text Available Abstract Background Aromatic amino acids play a critical role in protein-glycan interactions. Clusters of surface aromatic residues and their features may therefore be useful in distinguishing glycan-binding sites as well as predicting novel glycan-binding proteins. In this work, a structural bioinformatics approach was used to screen the Protein Data Bank (PDB for coplanar aromatic motifs similar to those found in known glycan-binding proteins. Results The proteins identified in the screen were significantly associated with carbohydrate-related functions according to gene ontology (GO enrichment analysis, and predicted motifs were found frequently within novel folds and glycan-binding sites not included in the training set. In addition to numerous binding sites predicted in structural genomics proteins of unknown function, one novel prediction was a surface motif (W34/W36/W192 in the tobacco pathogenesis-related protein, PR-5d. Phylogenetic analysis revealed that the surface motif is exclusive to a subfamily of PR-5 proteins from the Solanaceae family of plants, and is absent completely in more distant homologs. To confirm PR-5d's insoluble-polysaccharide binding activity, a cellulose-pulldown assay of tobacco proteins was performed and PR-5d was identified in the cellulose-binding fraction by mass spectrometry. Conclusions Based on the combined results, we propose that the putative binding site in PR-5d may be an evolutionary adaptation of Solanaceae plants including potato, tomato, and tobacco, towards defense against cellulose-containing pathogens such as species of the deadly oomycete genus, Phytophthora. More generally, the results demonstrate that coplanar aromatic clusters on protein surfaces are a structural signature of glycan-binding proteins, and can be used to computationally predict novel glycan-binding proteins from 3 D structure.

  4. Structural motif screening reveals a novel, conserved carbohydrate-binding surface in the pathogenesis-related protein PR-5d.

    Science.gov (United States)

    Doxey, Andrew C; Cheng, Zhenyu; Moffatt, Barbara A; McConkey, Brendan J

    2010-08-03

    Aromatic amino acids play a critical role in protein-glycan interactions. Clusters of surface aromatic residues and their features may therefore be useful in distinguishing glycan-binding sites as well as predicting novel glycan-binding proteins. In this work, a structural bioinformatics approach was used to screen the Protein Data Bank (PDB) for coplanar aromatic motifs similar to those found in known glycan-binding proteins. The proteins identified in the screen were significantly associated with carbohydrate-related functions according to gene ontology (GO) enrichment analysis, and predicted motifs were found frequently within novel folds and glycan-binding sites not included in the training set. In addition to numerous binding sites predicted in structural genomics proteins of unknown function, one novel prediction was a surface motif (W34/W36/W192) in the tobacco pathogenesis-related protein, PR-5d. Phylogenetic analysis revealed that the surface motif is exclusive to a subfamily of PR-5 proteins from the Solanaceae family of plants, and is absent completely in more distant homologs. To confirm PR-5d's insoluble-polysaccharide binding activity, a cellulose-pulldown assay of tobacco proteins was performed and PR-5d was identified in the cellulose-binding fraction by mass spectrometry. Based on the combined results, we propose that the putative binding site in PR-5d may be an evolutionary adaptation of Solanaceae plants including potato, tomato, and tobacco, towards defense against cellulose-containing pathogens such as species of the deadly oomycete genus, Phytophthora. More generally, the results demonstrate that coplanar aromatic clusters on protein surfaces are a structural signature of glycan-binding proteins, and can be used to computationally predict novel glycan-binding proteins from 3 D structure.

  5. Screening of the Open Source Malaria Box Reveals an Early Lead Compound for the Treatment of Alveolar Echinococcosis.

    Directory of Open Access Journals (Sweden)

    Britta Stadelmann

    2016-03-01

    Full Text Available The metacestode (larval stage of the tapeworm Echinococcus multilocularis causes alveolar echinococcosis (AE, a very severe and in many cases incurable disease. To date, benzimidazoles such as albendazole and mebendazole are the only approved chemotherapeutical treatment options. Benzimidazoles inhibit metacestode proliferation, but do not act parasiticidal. Thus, benzimidazoles have to be taken a lifelong, can cause adverse side effects such as hepatotoxicity, and are ineffective in some patients. We here describe a newly developed screening cascade for the evaluation of the in vitro efficacy of new compounds that includes assessment of parasiticidal activity. The Malaria Box from Medicines for Malaria Venture (MMV, comprised of 400 commercially available chemicals that show in vitro activity against Plasmodium falciparum, was repurposed. Primary screening was carried out at 10 μM by employing the previously described PGI assay, and resulted in the identification of 24 compounds that caused physical damage in metacestodes. Seven out of these 24 drugs were also active at 1 μM. Dose-response assays revealed that only 2 compounds, namely MMV665807 and MMV665794, exhibited an EC50 value below 5 μM. Assessments using human foreskin fibroblasts and Reuber rat hepatoma cells showed that the salicylanilide MMV665807 was less toxic for these two mammalian cell lines than for metacestodes. The parasiticidal activity of MMV665807 was then confirmed using isolated germinal layer cell cultures as well as metacestode vesicles by employing viability assays, and its effect on metacestodes was morphologically evaluated by electron microscopy. However, both oral and intraperitoneal application of MMV665807 to mice experimentally infected with E. multilocularis metacestodes did not result in any reduction of the parasite load.

  6. Rare occurrence of heart lesions in Pacific oysters Crassostrea gigas caused by an unknown bacterial infection.

    Science.gov (United States)

    Meyer, Gary R; Lowe, Geoffrey J; Bower, Susan M

    2017-09-20

    On rare occasions, small cream-coloured cysts have been observed in the heart and pericardial cavity of Pacific oysters Crassostrea gigas from British Columbia, Canada. Histopathology revealed the presence of large colonies of bacteria (up to 800 µm in diameter) causing significant host response and hypertrophy of the heart epithelium. The causative bacteria were characterized as follows: Gram-negative, coccoid to small rod-shaped, typically <1.5 µm in size, cell walls highly endowed with surface fimbriae and division via binary fission. Although these bacteria shared some morphological characteristics with the order Rickettsiales, they did not require an intracellular existence for multiplication. Unfortunately, a cultured isolate was not available, and a retrospective attempt to further characterize the bacteria using DNA sequence analysis of a fragment from the 16S rDNA region proved to be uninformative.

  7. Bacterial Infection Potato Tuber Soft Rot Disease Detection Based on Electronic Nose

    Directory of Open Access Journals (Sweden)

    Chang Zhiyong

    2017-11-01

    Full Text Available Soft rot is a severe bacterial disease of potatoes, and soft rot infection can cause significant economic losses during the storage period of potatoes. In this study, potato soft rot was selected as the research object, and a type of potato tuber soft rot disease early detection method based on the electronic nose technology was proposed. An optimized bionic electronic nose gas chamber and a scientific and reasonable sampling device were designed to detect a change in volatile substances of the infected soft rot disease of potato tuber. The infection of soft rot disease in potato tuber samples was detected and identified by using the RBF NN algorithm and SVM algorithm. The results revealed that the proposed bionic electronic nose system can be utilized for early detection of potato tuber soft rot disease. Through comparison and analysis, the recognition rate using the SVM algorithm reached up to 89.7%, and the results were superior to the RBF NN algorithm.

  8. A New Pharmacological Agent (AKB-4924) Stabilizes Hypoxia Inducible Factor (HIF) and Increases Skin Innate Defenses Against Bacterial Infection

    Science.gov (United States)

    Okumura, Cheryl Y.M.; Hollands, Andrew; Tran, Dan N.; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A.; Johnson, Randall S.; Nizet, Victor

    2013-01-01

    Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 (Akebia Therapeutics) increases HIF-1α levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and -resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinitobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections. PMID:22371073

  9. Simulated bacterial infection disrupts the circadian fluctuation of immune cells in wrinkle-lipped bats (Chaerephon plicatus

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    Philipp Weise

    2017-08-01

    Full Text Available Background Leukocyte concentrations follow a circadian pattern in mammals, with elevated values at times of potential contact with pathogens and parasites. We hypothesized that this pattern is disturbed after an immune challenge. Methods In Thailand, we captured wrinkle-lipped bats (Chaerephon plicatus, when they returned to their colony at dawn. We challenged half of the animals (experimental group with bacterial lipopolysaccharides and treated the others only with the carrier liquid (control group. We then compared body mass changes and differences in circulating immune cell counts at 8 h post-treatment. Results In experimental animals, we observed an increase in total leukocyte and neutrophil numbers of 17% and 95%, respectively. In control animals, concentrations of leukocytes decreased by 44% and those of neutrophils remained constant. Experimental treatment had no effect on lymphocytes, yet changes in eosinophil numbers were explained by sex. Eosinophils decreased by 66% in females and by 62% in males. Basophils and monocytes were rarest among all observed cell types and analysis was either impossible because of low numbers or yielded no significant effects, respectively. Discussion Our findings show that a simulated bacterial infection triggered a neutrophil-associated immune response in wrinkle-lipped bats, indicating a disruption of the diurnal fluctuation of immune cells. Our study suggests that bats exhibit circadian rhythms in immune cell counts. The magnitude of these fluctuations may vary across species according to specific-specific infection risks associated with colony sizes or specific roosting habits.

  10. Curative Treatment of Severe Gram-Negative Bacterial Infections by a New Class of Antibiotics Targeting LpxC

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    Nadine Lemaître

    2017-07-01

    Full Text Available The infectious diseases caused by multidrug-resistant bacteria pose serious threats to humankind. It has been suggested that an antibiotic targeting LpxC of the lipid A biosynthetic pathway in Gram-negative bacteria is a promising strategy for curing Gram-negative bacterial infections. However, experimental proof of this concept is lacking. Here, we describe our discovery and characterization of a biphenylacetylene-based inhibitor of LpxC, an essential enzyme in the biosynthesis of the lipid A component of the outer membrane of Gram-negative bacteria. The compound LPC-069 has no known adverse effects in mice and is effective in vitro against a broad panel of Gram-negative clinical isolates, including several multiresistant and extremely drug-resistant strains involved in nosocomial infections. Furthermore, LPC-069 is curative in a murine model of one of the most severe human diseases, bubonic plague, which is caused by the Gram-negative bacterium Yersinia pestis. Our results demonstrate the safety and efficacy of LpxC inhibitors as a new class of antibiotic against fatal infections caused by extremely virulent pathogens. The present findings also highlight the potential of LpxC inhibitors for clinical development as therapeutics for infections caused by multidrug-resistant bacteria.

  11. The alkaloid compound harmane increases the lifespan of Caenorhabditis elegans during bacterial infection, by modulating the nematode's innate immune response.

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    Henrik Jakobsen

    Full Text Available The nematode Caenorhabditis elegans has in recent years been proven to be a powerful in vivo model for testing antimicrobial compounds. We report here that the alkaloid compound Harmane (2-methyl-β-carboline increases the lifespan of nematodes infected with a human pathogen, the Shiga toxin-producing Escherichia coli O157:H7 strain EDL933 and several other bacterial pathogens. This was shown to be unrelated to the weak antibiotic effect of Harmane. Using GFP-expressing E. coli EDL933, we showed that Harmane does not lower the colonization burden in the nematodes. We also found that the expression of the putative immune effector gene F35E12.5 was up-regulated in response to Harmane treatment. This indicates that Harmane stimulates the innate immune response of the nematode; thereby increasing its lifespan during bacterial infection. Expression of F35E12.5 is predominantly regulated through the p38 MAPK pathway; however, intriguingly the lifespan extension resulting from Harmane was higher in p38 MAPK-deficient nematodes. This indicates that Harmane has a complex effect on the innate immune system of C. elegans. Harmane could therefore be a useful tool in the further research into C. elegans immunity. Since the innate immunity of C. elegans has a high degree of evolutionary conservation, drugs such as Harmane could also be possible alternatives to classic antibiotics. The C. elegans model could prove to be useful for selection and development of such drugs.

  12. The alkaloid compound harmane increases the lifespan of Caenorhabditis elegans during bacterial infection, by modulating the nematode's innate immune response.

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    Jakobsen, Henrik; Bojer, Martin S; Marinus, Martin G; Xu, Tao; Struve, Carsten; Krogfelt, Karen A; Løbner-Olesen, Anders

    2013-01-01

    The nematode Caenorhabditis elegans has in recent years been proven to be a powerful in vivo model for testing antimicrobial compounds. We report here that the alkaloid compound Harmane (2-methyl-β-carboline) increases the lifespan of nematodes infected with a human pathogen, the Shiga toxin-producing Escherichia coli O157:H7 strain EDL933 and several other bacterial pathogens. This was shown to be unrelated to the weak antibiotic effect of Harmane. Using GFP-expressing E. coli EDL933, we showed that Harmane does not lower the colonization burden in the nematodes. We also found that the expression of the putative immune effector gene F35E12.5 was up-regulated in response to Harmane treatment. This indicates that Harmane stimulates the innate immune response of the nematode; thereby increasing its lifespan during bacterial infection. Expression of F35E12.5 is predominantly regulated through the p38 MAPK pathway; however, intriguingly the lifespan extension resulting from Harmane was higher in p38 MAPK-deficient nematodes. This indicates that Harmane has a complex effect on the innate immune system of C. elegans. Harmane could therefore be a useful tool in the further research into C. elegans immunity. Since the innate immunity of C. elegans has a high degree of evolutionary conservation, drugs such as Harmane could also be possible alternatives to classic antibiotics. The C. elegans model could prove to be useful for selection and development of such drugs.

  13. Augmentation of Cationic Antimicrobial Peptide Production with Histone Deacetylase Inhibitors as a Novel Epigenetic Therapy for Bacterial Infections

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    Roshan D. Yedery

    2015-01-01

    Full Text Available The emergence of antibiotic resistance seriously threatens our ability to treat many common and medically important bacterial infections. Novel therapeutics are needed that can be used alone or in conjunction with antibiotics. Cationic antimicrobial peptides (CAMPs are important effectors of the host innate defense that exhibit broad-spectrum activity against a wide range of microorganisms. CAMPs are carried within phagocytic granules and are constitutively or inducibly expressed by multiple cell types, including epithelial cells. The role of histone modification enzymes, specifically the histone deacetylases (HDAC, in down-regulating the transcription of CAMP-encoding genes is increasingly appreciated as is the capacity of HDAC inhibitors (HDACi to block the action of HDACs to increase CAMP expression. The use of synthetic and natural HDACi molecules to increase CAMPs on mucosal surfaces, therefore, has potential therapeutic applications. Here, we review host and pathogen regulation of CAMP expression through the induction of HDACs and assess the therapeutic potential of natural and synthetic HDACi based on evidence from tissue culture systems, animal models, and clinical trials.

  14. Phenotypic T cell exhaustion in a murine model of bacterial infection in the setting of pre-existing malignancy.

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    Rohit Mittal

    Full Text Available While much of cancer immunology research has focused on anti-tumor immunity both systemically and within the tumor microenvironment, little is known about the impact of pre-existing malignancy on pathogen-specific immune responses. Here, we sought to characterize the antigen-specific CD8+ T cell response following a bacterial infection in the setting of pre-existing pancreatic adenocarcinoma. Mice with established subcutaneous pancreatic adenocarcinomas were infected with Listeria monocytogenes, and antigen-specific CD8+ T cell responses were compared to those in control mice without cancer. While the kinetics and magnitude of antigen-specific CD8+ T cell expansion and accumulation was comparable between the cancer and non-cancer groups, bacterial antigen-specific CD8+ T cells and total CD4+ and CD8+ T cells in cancer mice exhibited increased expression of the coinhibitory receptors BTLA, PD-1, and 2B4. Furthermore, increased inhibitory receptor expression was associated with reduced IFN-γ and increased IL-2 production by bacterial antigen-specific CD8+ T cells in the cancer group. Taken together, these data suggest that cancer's immune suppressive effects are not limited to the tumor microenvironment, but that pre-existing malignancy induces phenotypic exhaustion in T cells by increasing expression of coinhibitory receptors and may impair pathogen-specific CD8+ T cell functionality and differentiation.

  15. Direct Gram staining and its various benefits in the diagnosis of bacterial infections.

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    Boyanova, Lyudmila

    2018-01-01

    In the era of rapid development of molecular and other diagnostic methods, direct Gram staining (DGS) tends to remain in the background, although it can provide both microbiologists and clinicians numerous benefits. The aim of this review was to emphasize the importance of DGS for the diagnosis of many clinically important infections. A PubMed search was carried out using relevant keywords for articles published primarily since 2010. The DGS can provide early information for a timely diagnosis of infections, can reveal the causative agents of the infections even under suboptimal conditions of specimen collection, transport or identification methods, can detect the presence of rare/unusual pathogens, moreover, the method shows the specimen quality, by distinguishing between contamination and true infection, it can direct or change initial antibiotic treatment before the availability of culture results, can indicate the need of other methods for pathogen identification and, in some cases, can show the need for emergency attention such as urgent antibiotic therapy and surgical measures. Briefly, the DGS remains an easy, rapid, inexpensive and important method, which use should be encouraged in conditions of a standardized and controlled performance to avoid technical or interpretation errors.

  16. A Knockout Screen of ApiAP2 Genes Reveals Networks of Interacting Transcriptional Regulators Controlling the Plasmodium Life Cycle.

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    Modrzynska, Katarzyna; Pfander, Claudia; Chappell, Lia; Yu, Lu; Suarez, Catherine; Dundas, Kirsten; Gomes, Ana Rita; Goulding, David; Rayner, Julian C; Choudhary, Jyoti; Billker, Oliver

    2017-01-11

    A family of apicomplexa-specific proteins containing AP2 DNA-binding domains (ApiAP2s) was identified in malaria parasites. This family includes sequence-specific transcription factors that are key regulators of development. However, functions for the majority of ApiAP2 genes remain unknown. Here, a systematic knockout screen in Plasmodium berghei identified ten ApiAP2 genes that were essential for mosquito transmission: four were critical for the formation of infectious ookinetes, and three were required for sporogony. We describe non-essential functions for AP2-O and AP2-SP proteins in blood stages, and identify AP2-G2 as a repressor active in both asexual and sexual stages. Comparative transcriptomics across mutants and developmental stages revealed clusters of co-regulated genes with shared cis promoter elements, whose expression can be controlled positively or negatively by different ApiAP2 factors. We propose that stage-specific interactions between ApiAP2 proteins on partly overlapping sets of target genes generate the complex transcriptional network that controls the Plasmodium life cycle. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. Functional drug screening reveals anticonvulsants as enhancers of mTOR-independent autophagic killing of Mycobacterium tuberculosis through inositol depletion.

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    Schiebler, Mark; Brown, Karen; Hegyi, Krisztina; Newton, Sandra M; Renna, Maurizio; Hepburn, Lucy; Klapholz, Catherine; Coulter, Sarah; Obregón-Henao, Andres; Henao Tamayo, Marcela; Basaraba, Randall; Kampmann, Beate; Henry, Katherine M; Burgon, Joseph; Renshaw, Stephen A; Fleming, Angeleen; Kay, Robert R; Anderson, Karen E; Hawkins, Phillip T; Ordway, Diane J; Rubinsztein, David C; Floto, Rodrigo Andres

    2015-02-01

    Mycobacterium tuberculosis (MTB) remains a major challenge to global health made worse by the spread of multidrug resistance. We therefore examined whether stimulating intracellular killing of mycobacteria through pharmacological enhancement of macroautophagy might provide a novel therapeutic strategy. Despite the resistance of MTB to killing by basal autophagy, cell-based screening of FDA-approved drugs revealed two anticonvulsants, carbamazepine and valproic acid, that were able to stimulate autophagic killing of intracellular M. tuberculosis within primary human macrophages at concentrations achievable in humans. Using a zebrafish model, we show that carbamazepine can stimulate autophagy in vivo and enhance clearance of M. marinum, while in mice infected with a highly virulent multidrug-resistant MTB strain, carbamazepine treatment reduced bacterial burden, improved lung pathology and stimulated adaptive immunity. We show that carbamazepine induces antimicrobial autophagy through a novel, evolutionarily conserved, mTOR-independent pathway controlled by cellular depletion of myo-inositol. While strain-specific differences in susceptibility to in vivo carbamazepine treatment may exist, autophagy enhancement by repurposed drugs provides an easily implementable potential therapy for the treatment of multidrug-resistant mycobacterial infection. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

  18. Molecular signatures in Arabidopsis thaliana in response to insect attack and bacterial infection.

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    Barah, Pankaj; Winge, Per; Kusnierczyk, Anna; Tran, Diem Hong; Bones, Atle M

    2013-01-01

    Under the threat of global climatic change and food shortages, it is essential to take the initiative to obtain a comprehensive understanding of common and specific defence mechanisms existing in plant systems for protection against different types of biotic invaders. We have implemented an integrated approach to analyse the overall transcriptomic reprogramming and systems-level defence responses in the model plant species Arabidopsis thaliana (A. thaliana henceforth) during insect Brevicoryne brassicae (B. brassicae henceforth) and bacterial Pseudomonas syringae pv. tomato strain DC3000 (P. syringae henceforth) attacks. The main aim of this study was to identify the attacker-specific and general defence response signatures in A. thaliana when attacked by phloem-feeding aphids or pathogenic bacteria. The obtained annotated networks of differentially expressed transcripts indicated that members of transcription factor families, such as WRKY, MYB, ERF, BHLH and bZIP, could be crucial for stress-specific defence regulation in Arabidopsis during aphid and P. syringae attack. The defence response pathways, signalling pathways and metabolic processes associated with aphid attack and P. syringae infection partially overlapped. Components of several important biosynthesis and signalling pathways, such as salicylic acid (SA), jasmonic acid (JA), ethylene (ET) and glucosinolates, were differentially affected during the two the treatments. Several stress-regulated transcription factors were known to be associated with stress-inducible microRNAs. The differentially regulated gene sets included many signature transcription factors, and our co-expression analysis showed that they were also strongly co-expressed during 69 other biotic stress experiments. Defence responses and functional networks that were unique and specific to aphid or P. syringae stresses were identified. Furthermore, our analysis revealed a probable link between biotic stress and microRNAs in Arabidopsis and

  19. Association between reduction of plasma adiponectin levels and risk of bacterial infection after gastric cancer surgery.

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    Hiroshi Yamamoto

    Full Text Available BACKGROUND AND PURPOSE: Infections are important causes of postoperative morbidity after gastric surgery; currently, no factors have been identified that can predict postoperative infection. Adiponectin (ADN mediates energy metabolism and functions as an immunomodulator. Perioperative ADN levels and perioperative immune functioning could be mutually related. Here we evaluated a potential biological marker to reliably predict the incidence of postoperative infections to prevent such comorbidities. METHODS: We analyzed 150 consecutive patients who underwent elective gastric cancer surgery at the Shiga University of Medical Science Hospital (Shiga, Japan from 1997 to 2009; of these, most surgeries (n = 100 were performed 2008 onwards. The patient characteristics and surgery-related factors between two groups (with and without infection were compared by the paired t-test and χ(2 test, including preoperative ADN levels, postoperative day 1 ADN levels, and ADN ratio (postoperative ADN levels/preoperative ADN levels as baseline factors. Logistic regression analysis was performed to access the independent association between ADN ratio and postoperative infection. Finally, receiver operating curves (ROCs were constructed to examine its clinical utility. RESULTS: Sixty patients (40% experienced postoperative infections. The baseline values of age, American Society of Anesthesiologists physical status, total operating time, blood loss, surgical procedure, C-reactive protein (CRP levels, preoperative ADN levels, and ADN ratio were significantly different between groups. Logistic regression analysis using these factors indicated that type 2 diabetes mellitus (T2DM and ADN ratio were significantly independent variables (*p<0.05, ** p<0.01, respectively. ROC analysis revealed that the useful cutoff values (sensitivity/specificity for preoperative ADN levels, ADN ratio, blood loss, operating time, and CRP levels were 8.81(0.567/0.568, 0.76 (0

  20. Molecular signatures in Arabidopsis thaliana in response to insect attack and bacterial infection.

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    Pankaj Barah

    Full Text Available BACKGROUND: Under the threat of global climatic change and food shortages, it is essential to take the initiative to obtain a comprehensive understanding of common and specific defence mechanisms existing in plant systems for protection against different types of biotic invaders. We have implemented an integrated approach to analyse the overall transcriptomic reprogramming and systems-level defence responses in the model plant species Arabidopsis thaliana (A. thaliana henceforth during insect Brevicoryne brassicae (B. brassicae henceforth and bacterial Pseudomonas syringae pv. tomato strain DC3000 (P. syringae henceforth attacks. The main aim of this study was to identify the attacker-specific and general defence response signatures in A. thaliana when attacked by phloem-feeding aphids or pathogenic bacteria. RESULTS: The obtained annotated networks of differentially expressed transcripts indicated that members of transcription factor families, such as WRKY, MYB, ERF, BHLH and bZIP, could be crucial for stress-specific defence regulation in Arabidopsis during aphid and P. syringae attack. The defence response pathways, signalling pathways and metabolic processes associated with aphid attack and P. syringae infection partially overlapped. Components of several important biosynthesis and signalling pathways, such as salicylic acid (SA, jasmonic acid (JA, ethylene (ET and glucosinolates, were differentially affected during the two the treatments. Several stress-regulated transcription factors were known to be associated with stress-inducible microRNAs. The differentially regulated gene sets included many signature transcription factors, and our co-expression analysis showed that they were also strongly co-expressed during 69 other biotic stress experiments. CONCLUSIONS: Defence responses and functional networks that were unique and specific to aphid or P. syringae stresses were identified. Furthermore, our analysis revealed a probable link between

  1. A Perfect Storm: Increased Colonization and Failure of Vaccination Leads to Severe Secondary Bacterial Infection in Influenza Virus-Infected Obese Mice

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    Erik A. Karlsson

    2017-09-01

    Full Text Available Obesity is a risk factor for developing severe disease following influenza virus infection; however, the comorbidity of obesity and secondary bacterial infection, a serious complication of influenza virus infections, is unknown. To fill this gap in knowledge, lean and obese C57BL/6 mice were infected with a nonlethal dose of influenza virus followed by a nonlethal dose of Streptococcus pneumoniae. Strikingly, not only did significantly enhanced death occur in obese coinfected mice compared to lean controls, but also high mortality was seen irrespective of influenza virus strain, bacterial strain, or timing of coinfection. This result was unexpected, given that most influenza virus strains, especially seasonal human A and B viruses, are nonlethal in this model. Both viral and bacterial titers were increased in the upper respiratory tract and lungs of obese animals as early as days 1 and 2 post-bacterial infection, leading to a significant decrease in lung function. This increased bacterial load correlated with extensive cellular damage and upregulation of platelet-activating factor receptor, a host receptor central to pneumococcal invasion. Importantly, while vaccination of obese mice against either influenza virus or pneumococcus failed to confer protection, antibiotic treatment was able to resolve secondary bacterial infection-associated mortality. Overall, secondary bacterial pneumonia could be a widespread, unaddressed public health problem in an increasingly obese population.

  2. [Construction of a diagnostic prediction model of severe bacterial infection in febrile infants under 3 months old].

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    Villalobos Pinto, Enrique; Sánchez-Bayle, Marciano

    2017-12-01

    Fever is a common cause of paediatric admissions in emergency departments. An aetiological diagnosis is difficult to obtain in those less than 3 months of age, as they tend to have a higher rate of serious bacterial infection (SBI). The aim of this study is to find a predictor index of SBI in children under 3 months old with fever of unknown origin. A study was conducted on all children under 3 months of age with fever admitted to hospital, with additional tests being performed according to the clinical protocol. Rochester criteria for identifying febrile infants at low risk for SBI were also analysed. A predictive model for SBI and positive cultures was designed, including the following variables in the maximum model: C-reactive protein (CRP), procalcitonin (PCT), and meeting not less than four of the Rochester criteria. A total of 702 subjects were included, of which 22.64% had an SBI and 20.65% had positive cultures. Children who had SBI and a positive culture showed higher values of white cells, total neutrophils, CRP and PCT. A statistical significance was observed with less than 4 Rochester criteria, CRP and PCT levels, an SBI (area under the curve [AUC] 0.877), or for positive cultures (AUC 0.888). Using regression analysis a predictive index was calculated for SBI or a positive culture, with a sensitivity of 87.7 and 91%, a specificity of 70.1 and 87.7%, an LR+ of 2.93 and 3.62, and a LR- of 0.17 and 0.10, respectively. The predictive models are valid and slightly improve the validity of the Rochester criteria for positive culture in children less than 3 months admitted with fever. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. In vitro and in vivo evaluation of [18F]ciprofloxacin for the imaging of bacterial infections with PET

    International Nuclear Information System (INIS)

    Langer, Oliver; Brunner, Martin; Zeitlinger, Markus; Mueller, Ulrich; Lackner, Edith; Joukhadar, Christian; Mueller, Markus; Ziegler, Sophie; Minar, Erich; Dobrozemsky, Georg; Mitterhauser, Markus; Wadsak, Wolfgang; Dudczak, Robert; Kletter, Kurt

    2005-01-01

    The suitability of the 18 F-labelled fluoroquinolone antibiotic ciprofloxacin ([ 18 F]ciprofloxacin) for imaging of bacterial infections with positron emission tomography (PET) was assessed in vitro and in vivo. For the in vitro experiments, suspensions of various E. colistrains were incubated with different concentrations of [ 18 F]ciprofloxacin (0.01-5.0 μg/ml) and radioactivity retention was measured in a gamma counter. For the in vivo experiments, 725 ± 9 MBq [ 18 F]ciprofloxacin was injected intravenously into four patients with microbiologically proven bacterial soft tissue infections of the lower extremities and time-radioactivity curves were recorded in infected and uninfected tissue for 5 h after tracer injection. Binding of [ 18 F]ciprofloxacin to bacterial cells was rapid, non-saturable and readily reversible. Moreover, bacterial binding of the agent was similar in ciprofloxacin-resistant and ciprofloxacin-susceptible clinical isolates. These findings suggest that non-specific binding rather than specific binding to bacterial type II topoisomerase enzymes is the predominant mechanism of bacterial retention of the radiotracer. PET studies in the four patients with microbiologically proven bacterial soft tissue infections demonstrated locally increased radioactivity uptake in infected tissue, with peak ratios between infected and uninfected tissue ranging from 1.8 to 5.5. Radioactivity was not retained in infected tissue and appeared to wash out with a similar elimination half-life as in uninfected tissue, suggesting that the kinetics of [ 18 F]ciprofloxacin in infected tissue are governed by increased blood flow and vascular permeability due to local infection rather than by a binding process. Taken together, our results indicate that [ 18 F]ciprofloxacin is not suited as a bacteria-specific infection imaging agent for PET. (orig.)

  4. Relative roles of the cellular and humoral responses in the Drosophila host defense against three gram-positive bacterial infections.

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    Nadine T Nehme

    2011-03-01

    Full Text Available Two NF-kappaB signaling pathways, Toll and immune deficiency (imd, are required for survival to bacterial infections in Drosophila. In response to septic injury, these pathways mediate rapid transcriptional activation of distinct sets of effector molecules, including antimicrobial peptides, which are important components of a humoral defense response. However, it is less clear to what extent macrophage-like hemocytes contribute to host defense.In order to dissect the relative importance of humoral and cellular defenses after septic injury with three different gram-positive bacteria (Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus, we used latex bead pre-injection to ablate macrophage function in flies wildtype or mutant for various Toll and imd pathway components. We found that in all three infection models a compromised phagocytic system impaired fly survival--independently of concomitant Toll or imd pathway activation. Our data failed to confirm a role of the PGRP-SA and GNBP1 Pattern Recognition Receptors for phagocytosis of S. aureus. The Drosophila scavenger receptor Eater mediates the phagocytosis by hemocytes or S2 cells of E. faecalis and S. aureus, but not of M. luteus. In the case of M. luteus and E. faecalis, but not S. aureus, decreased survival due to defective phagocytosis could be compensated for by genetically enhancing the humoral immune response.Our results underscore the fundamental importance of both cellular and humoral mechanisms in Drosophila immunity and shed light on the balance between these two arms of host defense depending on the invading pathogen.

  5. Evaluation of anti-peptidoglycan aptamers labeled with Technetium-99m for in vivo bacterial infection identification

    International Nuclear Information System (INIS)

    Ferreira, Ieda Mendes

    2017-01-01

    Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. In a previous work, we selected two aptamers for peptidoglycan (the main constituent of bacterial cell walls) termed Antibac1 and Antibac2. In the present study, the characterization of these aptamers was completed, and the dissociation coefficients (K_d) were determined. The aptamers were further labeled with "9"9"mTc and evaluated for bacterial infection diagnosis by scintigraphy. The K_d obtained for Antibac1 was of 0.415 ± 0.047 μM and for Antibac2 of 1.261 ± 0.280 μM. The direct labeling method with "9"9"mTc allowed radiolabel yields higher than 90% and the radiolabel stability in saline, plasma and cysteine excess indicated that the process was suitable for labeling of both aptamers. The "9"9"mTc-aptamers are prone to bind to plasma proteins: 39.5% ± 2.9% (1 h) and 43.6% ± 1.2% (3 h) for "9"9"mTc-Antibac1; 37.6% ± 2.0% (1 h) and 40.9% ± 0% (3 h) for "9"9"mTc-Antibac2. The blood clearance half-life for "9"9"mTc-Antibac1 was of 41.26 min and for the "9"9"mTc-Antibac2 of 31.58 min. The "9"9"mTc-Antibac1 in the group infected with S. aureus presented a target/non-target ratio of 2.81 ± 0.67, significantly higher than verified for the "9"9"mTc-library (control): 1.52 ± 0.07. In the model with C. albicans infection the target/non-target ratio for "9"9"mTc-Antibac1 was 1.46 ± 0.11, similar that obtained for the "9"9"mTc-library in the same model: 1.52 ± 0.05. The "9"9"mTc-Antibac2 in the group infected with S. aureus showed a target/non-target ratio of 2.61 ± 0.66, statistically higher than achieved for the "9"9"mTc-library in the same infection model: 1.52 ± 0.07. In the group infected with C. albicans this ratio for "9"9"mTc-Antibac2 was 1.75 ± 0.19, it was significantly higher than verified for the "9"9"mTc-library: 1.52 ± 0.05. The scintigraphic images for all groups

  6. Pathway-based analysis of genome-wide siRNA screens reveals the regulatory landscape of APP processing.

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    Luiz Miguel Camargo

    Full Text Available The progressive aggregation of Amyloid-β (Aβ in the brain is a major trait of Alzheimer's Disease (AD. Aβ is produced as a result of proteolytic processing of the β-amyloid precursor protein (APP. Processing of APP is mediated by multiple enzymes, resulting in the production of distinct peptide products: the non-amyloidogenic peptide sAPPα and the amyloidogenic peptides sAPPβ, Aβ40, and Aβ42. Using a pathway-based approach, we analyzed a large-scale siRNA screen that measured the production of different APP proteolytic products. Our analysis identified many of the biological processes/pathways that are known to regulate APP processing and have been implicated in AD pathogenesis, as well as revealing novel regulatory mechanisms. Furthermore, we also demonstrate that some of these processes differentially regulate APP processing, with some mechanisms favouring production of certain peptide species over others. For example, synaptic transmission having a bias towards regulating Aβ40 production over Aβ42 as well as processes involved in insulin and pancreatic biology having a bias for sAPPβ production over sAPPα. In addition, some of the pathways identified as regulators of APP processing contain genes (CLU, BIN1, CR1, PICALM, TREM2, SORL1, MEF2C, DSG2, EPH1A recently implicated with AD through genome wide association studies (GWAS and associated meta-analysis. In addition, we provide supporting evidence and a deeper mechanistic understanding of the role of diabetes in AD. The identification of these processes/pathways, their differential impact on APP processing, and their relationships to each other, provide a comprehensive systems biology view of the "regulatory landscape" of APP.

  7. A complex regulatory network coordinating cell cycles during C. elegans development is revealed by a genome-wide RNAi screen.

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    Roy, Sarah H; Tobin, David V; Memar, Nadin; Beltz, Eleanor; Holmen, Jenna; Clayton, Joseph E; Chiu, Daniel J; Young, Laura D; Green, Travis H; Lubin, Isabella; Liu, Yuying; Conradt, Barbara; Saito, R Mako

    2014-02-28

    The development and homeostasis of multicellular animals requires precise coordination of cell division and differentiation. We performed a genome-wide RNA interference screen in Caenorhabditis elegans to reveal the components of a regulatory network that promotes developmentally programmed cell-cycle quiescence. The 107 identified genes are predicted to constitute regulatory networks that are conserved among higher animals because almost half of the genes are represented by clear human orthologs. Using a series of mutant backgrounds to assess their genetic activities, the RNA interference clones displaying similar properties were clustered to establish potential regulatory relationships within the network. This approach uncovered four distinct genetic pathways controlling cell-cycle entry during intestinal organogenesis. The enhanced phenotypes observed for animals carrying compound mutations attest to the collaboration between distinct mechanisms to ensure strict developmental regulation of cell cycles. Moreover, we characterized ubc-25, a gene encoding an E2 ubiquitin-conjugating enzyme whose human ortholog, UBE2Q2, is deregulated in several cancers. Our genetic analyses suggested that ubc-25 acts in a linear pathway with cul-1/Cul1, in parallel to pathways employing cki-1/p27 and lin-35/pRb to promote cell-cycle quiescence. Further investigation of the potential regulatory mechanism demonstrated that ubc-25 activity negatively regulates CYE-1/cyclin E protein abundance in vivo. Together, our results show that the ubc-25-mediated pathway acts within a complex network that integrates the actions of multiple molecular mechanisms to control cell cycles during development. Copyright © 2014 Roy et al.

  8. Pleural effusion adenosine deaminase: a candidate biomarker to discriminate between Gram-negative and Gram-positive bacterial infections of the pleural space

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    Ruolin Li

    2016-05-01

    Full Text Available OBJECTIVES: Delay in the treatment of pleural infection may contribute to its high mortality. In this retrospective study, we aimed to evaluate the diagnostic accuracy of pleural adenosine deaminase in discrimination between Gram-negative and Gram-positive bacterial infections of the pleural space prior to selecting antibiotics. METHODS: A total of 76 patients were enrolled and grouped into subgroups according to Gram staining: 1 patients with Gram-negative bacterial infections, aged 53.2±18.6 years old, of whom 44.7% had empyemas and 2 patients with Gram-positive bacterial infections, aged 53.5±21.5 years old, of whom 63.1% had empyemas. The pleural effusion was sampled by thoracocentesis and then sent for adenosine deaminase testing, biochemical testing and microbiological culture. The Mann-Whitney U test was used to examine the differences in adenosine deaminase levels between the groups. Correlations between adenosine deaminase and specified variables were also quantified using Spearman’s correlation coefficient. Moreover, receiver operator characteristic analysis was performed to evaluate the diagnostic accuracy of pleural effusion adenosine deaminase. RESULTS: Mean pleural adenosine deaminase levels differed significantly between Gram-negative and Gram-positive bacterial infections of the pleural space (191.8±32.1 U/L vs 81.0±16.9 U/L, p<0.01. The area under the receiver operator characteristic curve was 0.689 (95% confidence interval: 0.570, 0.792, p<0.01 at the cutoff value of 86 U/L. Additionally, pleural adenosine deaminase had a sensitivity of 63.2% (46.0-78.2%; a specificity of 73.7% (56.9-86.6%; positive and negative likelihood ratios of 2.18 and 0.50, respectively; and positive and negative predictive values of 70.6% and 66.7%, respectively. CONCLUSIONS: Pleural effusion adenosine deaminase is a helpful alternative biomarker for early and quick discrimination of Gram-negative from Gram-positive bacterial infections of the

  9. Diagnosis of bacterial infection

    African Journals Online (AJOL)

    direct or indirect evidence of a compatible bacterial pathogen. Inflammation may be .... cardinal features (fever, confusion, headache and neck stiffness). .... specificity, inappropriate indications or poor sampling technique may diminish this ...

  10. Risk factors for possible serious bacterial infection in a rural cohort of young infants in central India

    Directory of Open Access Journals (Sweden)

    Marie E. Wang

    2016-10-01

    Full Text Available Abstract Background Possible serious bacterial infection (PBSI is a major cause of neonatal mortality worldwide. We studied risk factors for PSBI in a large rural population in central India where facility deliveries have increased as a result of a government financial assistance program. Methods We studied 37,379 pregnant women and their singleton live born infants with birth weight ≥ 1.5 kg from 20 rural primary health centers around Nagpur, India, using data from the 2010–13 population-based Maternal and Newborn Health Registry supported by NICHD’s Global Network for Women’s and Children’s Health Research. Factors associated with PSBI were identified using multivariable Poisson regression. Results Two thousand one hundred twenty-three infants (6 % had PSBI. Risk factors for PSBI included nulliparity (RR 1.13, 95 % CI 1.03–1.23, parity > 2 (RR 1.30, 95 % CI 1.07–1.57 compared to parity 1–2, first antenatal care visit in the 2nd/3rd trimester (RR 1.46, 95 % CI 1.08–1.98 compared to 1st trimester, administration of antenatal corticosteroids (RR 2.04, 95 % CI 1.60–2.61, low birth weight (RR 3.10, 95 % CI 2.17–4.42, male sex (RR 1.20, 95 % CI 1.10–1.31 and lack of early initiation of breastfeeding (RR 3.87, 95 % CI 2.69–5.58. Conclusion Infants who are low birth weight, born to mothers who present late to antenatal care or receive antenatal corticosteroids, or born to nulliparous women or those with a parity > 2, could be targeted for interventions before and after delivery to improve early recognition of signs and symptoms of PSBI and prompt referral. There also appears to be a need for a renewed focus on promoting early initiation of breastfeeding following delivery in facilities. Trial registration This trial is registered at ClinicalTrials.gov ( NCT01073475 .

  11. In Situ Forming and H2O2-Releasing Hydrogels for Treatment of Drug-Resistant Bacterial Infections.

    Science.gov (United States)

    Lee, Yunki; Choi, Kyong-Hoon; Park, Kyung Min; Lee, Jong-Min; Park, Bong Joo; Park, Ki Dong

    2017-05-24

    Various types of commercialized wound dressings (e.g., films, foams, gels, and nanofiber meshes) have been clinically used as a physical barrier against bacterial invasion and as wound-healing materials. Although these dressings can protect the wounded tissue from the external environment, they cannot treat the wounds that are already infected with bacteria. Herein, we report in situ H 2 O 2 -releasing hydrogels as an active wound dressing with antibacterial properties for treatment of drug-resistant bacterial infection. In this study, H 2 O 2 was used for two major purposes: (1) in situ gel formation via a horseradish peroxidase (HRP)/H 2 O 2 -triggered cross-linking reaction, and (2) antibacterial activity of the hydrogel via its oxidative effects. We found that there were residual H 2 O 2 in the matrix after in situ HRP-catalyzed gelling, and varying the feed amount of H 2 O 2 (1-10 mM; used to make hydrogels) enabled control of H 2 O 2 release kinetics within a range of 2-509 μM. In addition, although the gelatin-hydroxyphenyl propionic acid (GH) gel called "GH 10" (showing the greatest H 2 O 2 release, 509 μM) slightly decreased cell viability (to 82-84%) of keratinocyte (HaCaT) and fibroblast (L-929) cells in in vitro assays, none of the hydrogels showed significant cytotoxicity toward tissues in in vivo skin irritation tests. When the H 2 O 2 -releasing hydrogels that promote in vivo wound healing, were applied to various bacterial strains in vitro and ex vivo, they showed strong killing efficiency toward Gram-positive bacteria including Staphylococcus aureus, S. epidermidis, and clinical isolate of methicillin-resistant S. aureus (MRSA, drug-resistant bacteria), where the antimicrobial effect was dependent on the concentration of the H 2 O 2 released. The present study suggests that our hydrogels have great potential as an injectable/sprayable antimicrobial dressing with biocompatibility and antibacterial activity against drug-resistant bacteria including

  12. RNA transcriptional biosignature analysis for identifying febrile infants with serious bacterial infections in the emergency department: a feasibility study.

    Science.gov (United States)

    Mahajan, Prashant; Kuppermann, Nathan; Suarez, Nicolas; Mejias, Asuncion; Casper, Charlie; Dean, J Michael; Ramilo, Octavio

    2015-01-01

    To develop the infrastructure and demonstrate the feasibility of conducting microarray-based RNA transcriptional profile analyses for the diagnosis of serious bacterial infections in febrile infants 60 days and younger in a multicenter pediatric emergency research network. We designed a prospective multicenter cohort study with the aim of enrolling more than 4000 febrile infants 60 days and younger. To ensure success of conducting complex genomic studies in emergency department (ED) settings, we established an infrastructure within the Pediatric Emergency Care Applied Research Network, including 21 sites, to evaluate RNA transcriptional profiles in young febrile infants. We developed a comprehensive manual of operations and trained site investigators to obtain and process blood samples for RNA extraction and genomic analyses. We created standard operating procedures for blood sample collection, processing, storage, shipping, and analyses. We planned to prospectively identify, enroll, and collect 1 mL blood samples for genomic analyses from eligible patients to identify logistical issues with study procedures. Finally, we planned to batch blood samples and determined RNA quantity and quality at the central microarray laboratory and organized data analysis with the Pediatric Emergency Care Applied Research Network data coordinating center. Below we report on establishment of the infrastructure and the feasibility success in the first year based on the enrollment of a limited number of patients. We successfully established the infrastructure at 21 EDs. Over the first 5 months we enrolled 79% (74 of 94) of eligible febrile infants. We were able to obtain and ship 1 mL of blood from 74% (55 of 74) of enrolled participants, with at least 1 sample per participating ED. The 55 samples were shipped and evaluated at the microarray laboratory, and 95% (52 of 55) of blood samples were of adequate quality and contained sufficient RNA for expression analysis. It is possible to

  13. Individual decision making in relation to participation in cardiovascular screening: a study of revealed and stated preferences.

    Science.gov (United States)

    Søgaard, Rikke; Lindholt, Jes; Gyrd-Hansen, Dorte

    2013-02-01

    The (cost-)effectiveness of a screening programme may be strongly influenced by the participation rate. The objective of this study was to compare participants' and non-participants' motives for the attendance decision as well as their overall preferences for participation in cardiovascular disease screening. This study sampled 1053 participants and 1006 non-participants from a screening trial and randomly allocated the participants to receive different levels of additional information about the screening programme. An ad hoc survey questionnaire about doubt and arguments in relation to the participation decision was given to participants and non-participants along with a contingent valuation task. Among participants, 5% had doubt about participation and the most frequent argument was that they did not want the test result. Among non-participants, 40% would reconsider their non-participation decision after having received additional information while the remainder 60% stood by their decision and provided explicit arguments for it. After having received additional information the participants still valued the programme significantly higher than non-participants, but the difference was relatively small. Participants and non-participants in cardiovascular screening programmes seem to have different strengths of preferences, which signals that their behavioural choice is founded in rational thinking. Furthermore, it appears that additional information and a second reflection about the participation decision may affect a substantial proportion of non-participants to reverse their decision, a finding that should receive policy interest.

  14. In silico activity profiling reveals the mechanism of action of antimalarials discovered in a high-throughput screen

    Science.gov (United States)

    Plouffe, David; Brinker, Achim; McNamara, Case; Henson, Kerstin; Kato, Nobutaka; Kuhen, Kelli; Nagle, Advait; Adrián, Francisco; Matzen, Jason T.; Anderson, Paul; Nam, Tae-gyu; Gray, Nathanael S.; Chatterjee, Arnab; Janes, Jeff; Yan, S. Frank; Trager, Richard; Caldwell, Jeremy S.; Schultz, Peter G.; Zhou, Yingyao; Winzeler, Elizabeth A.

    2008-01-01

    The growing resistance to current first-line antimalarial drugs represents a major health challenge. To facilitate the discovery of new antimalarials, we have implemented an efficient and robust high-throughput cell-based screen (1,536-well format) based on proliferation of Plasmodium falciparum (Pf) in erythrocytes. From a screen of ≈1.7 million compounds, we identified a diverse collection of ≈6,000 small molecules comprised of >530 distinct scaffolds, all of which show potent antimalarial activity (antimalarials were identified in this screen, thus validating our approach. In addition, we identified many novel chemical scaffolds, which likely act through both known and novel pathways. We further show that in some cases the mechanism of action of these antimalarials can be determined by in silico compound activity profiling. This method uses large datasets from unrelated cellular and biochemical screens and the guilt-by-association principle to predict which cellular pathway and/or protein target is being inhibited by select compounds. In addition, the screening method has the potential to provide the malaria community with many new starting points for the development of biological probes and drugs with novel antiparasitic activities. PMID:18579783

  15. The study of the morphological features of autophagy as a type of programmed death of plant cells under the condition of bacterial infection

    Directory of Open Access Journals (Sweden)

    Сергій Іванович Шевченко

    2016-09-01

    Full Text Available The ultrastructure of the destruction of the plant cells protoplast is studied under the condition of bacterial infection. According to the autophagy processes in animal cells, the morphological ways of plant cells autophagy – vacuolization of cytoplasm, condensation and decondensation of the nuclear mass, multivesicular nucleation, phagophore expansion and macroautophagosome ripening, autophagolysosome formation by the way of tonoplast invagination, mitophagy phenomenon are determined. The places of the final degradation of the ruined cytoplasm in the vacuoles of destroyed cells are shown

  16. Identification of genes important for cutaneous function revealed by a large scale reverse genetic screen in the mouse.

    Directory of Open Access Journals (Sweden)

    Tia DiTommaso

    2014-10-01

    Full Text Available The skin is a highly regenerative organ which plays critical roles in protecting the body and sensing its environment. Consequently, morbidity and mortality associated with skin defects represent a significant health issue. To identify genes important in skin development and homeostasis, we have applied a high throughput, multi-parameter phenotype screen to the conditional targeted mutant mice generated by the Wellcome Trust Sanger Institute's Mouse Genetics Project (Sanger-MGP. A total of 562 different mouse lines were subjected to a variety of tests assessing cutaneous expression, macroscopic clinical disease, histological change, hair follicle cycling, and aberrant marker expression. Cutaneous lesions were associated with mutations in 23 different genes. Many of these were not previously associated with skin disease in the organ (Mysm1, Vangl1, Trpc4ap, Nom1, Sparc, Farp2, and Prkab1, while others were ascribed new cutaneous functions on the basis of the screening approach (Krt76, Lrig1, Myo5a, Nsun2, and Nf1. The integration of these skin specific screening protocols into the Sanger-MGP primary phenotyping pipelines marks the largest reported reverse genetic screen undertaken in any organ and defines approaches to maximise the productivity of future projects of this nature, while flagging genes for further characterisation.

  17. A Genomewide Screen for Tolerance to Cationic Drugs Reveals Genes Important for Potassium Homeostasis in Saccharomyces cerevisiae

    Czech Academy of Sciences Publication Activity Database

    Barreto, L.; Canadell, D.; Petrezsélyová, Silvia; Navarrete, C.; Marešová, Lydie; Peréz-Valle, J.; Herrera, R.; Olier, I.; Giraldo, J.; Sychrová, Hana; Yenush, L.; Ramos, J.; Ariňo, J.

    2011-01-01

    Roč. 10, č. 9 (2011), s. 1241-1250 ISSN 1535-9778 R&D Projects: GA MŠk(CZ) LC531; GA AV ČR(CZ) IAA500110801 Institutional research plan: CEZ:AV0Z50110509 Keywords : Potassium homeostasis * Saccharomyces cerevisiae * genomewide screen Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.604, year: 2011

  18. High-throughput screening reveals alsterpaullone, 2-cyanoethyl as a potent p27Kip1 transcriptional inhibitor.

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    Brandon J Walters

    Full Text Available p27Kip1 is a cell cycle inhibitor that prevents cyclin dependent kinase (CDK/cyclin complexes from phosphorylating their targets. p27Kip1 is a known tumor suppressor, as the germline loss of p27Kip1 results in sporadic pituitary formation in aged rodents, and its presence in human cancers is indicative of a poor prognosis. In addition to its role in cancer, loss of p27Kip1 results in regenerative phenotypes in some tissues and maintenance of stem cell pluripotency, suggesting that p27Kip1 inhibitors could be beneficial for tissue regeneration. Because p27Kip1 is an intrinsically disordered protein, identifying direct inhibitors of the p27Kip1 protein is difficult. Therefore, we pursued a high-throughput screening strategy to identify novel p27Kip1 transcriptional inhibitors. We utilized a luciferase reporter plasmid driven by the p27Kip1 promoter to transiently transfect HeLa cells and used cyclohexamide as a positive control for non-specific inhibition. We screened a "bioactive" library consisting of 8,904 (4,359 unique compounds, of which 830 are Food and Drug Administration (FDA approved. From this screen, we successfully identified 111 primary hits with inhibitory effect against the promoter of p27Kip1. These hits were further refined using a battery of secondary screens. Here we report four novel p27Kip1 transcriptional inhibitors, and further demonstrate that our most potent hit compound (IC50 = 200 nM Alsterpaullone 2-cyanoethyl, inhibits p27Kip1 transcription by preventing FoxO3a from binding to the p27Kip1 promoter. This screen represents one of the first attempts to identify inhibitors of p27Kip1 and may prove useful for future tissue regeneration studies.

  19. De Novo Endotoxin-Induced Production of Antibodies against the Bile Salt Export Pump Associated with Bacterial Infection following Major Hepatectomy

    Directory of Open Access Journals (Sweden)

    Kun-Ming Chan

    2018-01-01

    Full Text Available Background. Clinically severe infection-related inflammation after major liver resection may cause hyperbilirubinemia. This study aims to clarify the impact of bacterial infection and endotoxins on the hepatobiliary transporter system and to explore possible mechanisms of endotoxin-related postoperative hyperbilirubinemia. Method. Mice that underwent major hepatectomy with removal of at least 70% of liver volume were exposed to lipopolysaccharide (LPS at different dosages. Subsequently, hepatobiliary transporter compounds related to bile salt excretion were further investigated. Results. The expression of genes related to hepatobiliary transporter compounds was not significantly different in the liver tissue of mice after major hepatectomy and LPS exposure. However, bile salt export pump (BSEP protein expression within the liver tissue of mice treated with LPS after major hepatectomy was relatively weaker and was even further reduced in the high-dose LPS group. The formation of antibodies against the BSEP in response to endotoxin exposure was also detected. Conclusion. This study illustrates a possible mechanism whereby the dysfunction of hepatobiliary transporter systems caused by endotoxin-induced autoantibodies may be involved in the development of postoperative jaundice associated with bacterial infection after major hepatectomy.

  20. Genomic characterization and expression profiles upon bacterial infection of a novel cystatin B homologue from disk abalone (Haliotis discus discus).

    Science.gov (United States)

    Premachandra, H K A; Wan, Qiang; Elvitigala, Don Anushka Sandaruwan; De Zoysa, Mahanama; Choi, Cheol Young; Whang, Ilson; Lee, Jehee

    2012-12-01

    Cystatins are a large family of cysteine proteinase inhibitors which are involved in diverse biological and pathological processes. In the present study, we identified a gene related to cystatin superfamily, AbCyt B, from disk abalone Haliotis discus discus by expressed sequence tag (EST) analysis and BAC library screening. The complete cDNA sequence of AbCyt B is comprised of 1967 nucleotides with a 306 bp open reading frame (ORF) encoding for 101 amino acids. The amino acid sequence consists of a single cystatin-like domain, which has a cysteine proteinase inhibitor signature, a conserved Gly in N-terminal region, QVVAG motif and a variant of PW motif. No signal peptide, disulfide bonds or carbohydrate side chains were identified. Analysis of deduced amino acid sequence revealed that AbCyt B shares up to 44.7% identity and 65.7% similarity with the cystatin B genes from other organisms. The genomic sequence of AbCyt B is approximately 8.4 Kb, consisting of three exons and two introns. Phylogenetic tree analysis showed that AbCyt B was closely related to the cystatin B from pacific oyster (Crassostrea gigas) under the family 1.Functional analysis of recombinant AbCyt B protein exhibited inhibitory activity against the papain, with almost 84% inhibition at a concentration of 3.5 μmol/L. In tissue expression analysis, AbCyt B transcripts were expressed abundantly in the hemocyte, gill, mantle, and digestive tract, while weakly in muscle, testis, and hepatopancreas. After the immune challenge with Vibrio parahemolyticus, the AbCyt B showed significant (P<0.05) up-regulation of relative mRNA expression in gill and hemocytes at 24 and 6 h of post infection, respectively. These results collectively suggest that AbCyst B is a potent inhibitor of cysteine proteinases and is also potentially involved in immune responses against invading bacterial pathogens in abalone. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Brain transcriptome-wide screen for HIV-1 Nef protein interaction partners reveals various membrane-associated proteins.

    Directory of Open Access Journals (Sweden)

    Ellen C Kammula

    Full Text Available HIV-1 Nef protein contributes essentially to the pathology of AIDS by a variety of protein-protein-interactions within the host cell. The versatile functionality of Nef is partially attributed to different conformational states and posttranslational modifications, such as myristoylation. Up to now, many interaction partners of Nef have been identified using classical yeast two-hybrid screens. Such screens rely on transcriptional activation of reporter genes in the nucleus to detect interactions. Thus, the identification of Nef interaction partners that are integral membrane proteins, membrane-associated proteins or other proteins that do not translocate into the nucleus is hampered. In the present study, a split-ubiquitin based yeast two-hybrid screen was used to identify novel membrane-localized interaction partners of Nef. More than 80% of the hereby identified interaction partners of Nef are transmembrane proteins. The identified hits are GPM6B, GPM6A, BAP31, TSPAN7, CYB5B, CD320/TCblR, VSIG4, PMEPA1, OCIAD1, ITGB1, CHN1, PH4, CLDN10, HSPA9, APR-3, PEBP1 and B3GNT, which are involved in diverse cellular processes like signaling, apoptosis, neurogenesis, cell adhesion and protein trafficking or quality control. For a subfraction of the hereby identified proteins we present data supporting their direct interaction with HIV-1 Nef. We discuss the results with respect to many phenotypes observed in HIV infected cells and patients. The identified Nef interaction partners may help to further elucidate the molecular basis of HIV-related diseases.

  2. A directed RNAi screen based on larval growth arrest reveals new modifiers of C. elegans insulin signaling.

    Directory of Open Access Journals (Sweden)

    Ola Billing

    Full Text Available Genes regulating Caenorhabditis elegans insulin/IGF signaling (IIS have largely been identified on the basis of their involvement in dauer development or longevity. A third IIS phenotype is the first larval stage (L1 diapause, which is also influenced by asna-1, a regulator of DAF-28/insulin secretion. We reasoned that new regulators of IIS strength might be identified in screens based on the L1 diapause and the asna-1 phenotype. Eighty- six genes were selected for analysis by virtue of their predicted interaction with ASNA-1 and screened for asna-1-like larval arrest. ykt-6, mrps-2, mrps-10 and mrpl-43 were identified as genes which, when inactivated, caused larval arrest without any associated feeding defects. Several tests indicated that IIS strength was weaker and that insulin secretion was defective in these animals. This study highlights the role of the Golgi network and the mitochondria in insulin secretion and provides a new list of genes that modulate IIS in C. elegans.

  3. A direct pre-screen for marine bacteria producing compounds inhibiting quorum sensing reveals diverse planktonic bacteria that are bioactive.

    Science.gov (United States)

    Linthorne, Jamie S; Chang, Barbara J; Flematti, Gavin R; Ghisalberti, Emilio L; Sutton, David C

    2015-02-01

    A promising new strategy in antibacterial research is inhibition of the bacterial communication system termed quorum sensing. In this study, a novel and rapid pre-screening method was developed to detect the production of chemical inhibitors of this system (quorum-quenching compounds) by bacteria isolated from marine and estuarine waters. This method involves direct screening of mixed populations on an agar plate, facilitating specific isolation of bioactive colonies. The assay showed that between 4 and 46 % of culturable bacteria from various samples were bioactive, and of the 95 selectively isolated bacteria, 93.7 % inhibited Vibrio harveyi bioluminescence without inhibiting growth, indicating potential production of quorum-quenching compounds. Of the active isolates, 21 % showed further activity against quorum-sensing-regulated pigment production by Serratia marcescens. The majority of bioactive isolates were identified by 16S ribosomal DNA (rDNA) amplification and sequencing as belonging to the genera Vibrio and Pseudoalteromonas. Extracts of two strongly bioactive Pseudoalteromonas isolates (K1 and B2) were quantitatively assessed for inhibition of growth and quorum-sensing-regulated processes in V. harveyi, S. marcescens and Chromobacterium violaceum. Extracts of the isolates reduced V. harveyi bioluminescence by as much as 98 % and C. violaceum pigment production by 36 % at concentrations which had no adverse effect on growth. The activity found in the extracts indicated that the isolates may produce quorum-quenching compounds. This study further supports the suggestion that quorum quenching may be a common attribute among culturable planktonic marine and estuarine bacteria.

  4. RNAi screening of subtracted transcriptomes reveals tumor suppression by taurine-activated GABAA receptors involved in volume regulation

    Science.gov (United States)

    van Nierop, Pim; Vormer, Tinke L.; Foijer, Floris; Verheij, Joanne; Lodder, Johannes C.; Andersen, Jesper B.; Mansvelder, Huibert D.; te Riele, Hein

    2018-01-01

    To identify coding and non-coding suppressor genes of anchorage-independent proliferation by efficient loss-of-function screening, we have developed a method for enzymatic production of low complexity shRNA libraries from subtracted transcriptomes. We produced and screened two LEGO (Low-complexity by Enrichment for Genes shut Off) shRNA libraries that were enriched for shRNA vectors targeting coding and non-coding polyadenylated transcripts that were reduced in transformed Mouse Embryonic Fibroblasts (MEFs). The LEGO shRNA libraries included ~25 shRNA vectors per transcript which limited off-target artifacts. Our method identified 79 coding and non-coding suppressor transcripts. We found that taurine-responsive GABAA receptor subunits, including GABRA5 and GABRB3, were induced during the arrest of non-transformed anchor-deprived MEFs and prevented anchorless proliferation. We show that taurine activates chloride currents through GABAA receptors on MEFs, causing seclusion of cell volume in large membrane protrusions. Volume seclusion from cells by taurine correlated with reduced proliferation and, conversely, suppression of this pathway allowed anchorage-independent proliferation. In human cholangiocarcinomas, we found that several proteins involved in taurine signaling via GABAA receptors were repressed. Low GABRA5 expression typified hyperproliferative tumors, and loss of taurine signaling correlated with reduced patient survival, suggesting this tumor suppressive mechanism operates in vivo. PMID:29787571

  5. A kinome-wide RNAi screen in Drosophila Glia reveals that the RIO kinases mediate cell proliferation and survival through TORC2-Akt signaling in glioblastoma.

    Directory of Open Access Journals (Sweden)

    Renee D Read

    Full Text Available Glioblastoma, the most common primary malignant brain tumor, is incurable with current therapies. Genetic and molecular analyses demonstrate that glioblastomas frequently display mutations that activate receptor tyrosine kinase (RTK and Pi-3 kinase (PI3K signaling pathways. In Drosophila melanogaster, activation of RTK and PI3K pathways in glial progenitor cells creates malignant neoplastic glial tumors that display many features of human glioblastoma. In both human and Drosophila, activation of the RTK and PI3K pathways stimulates Akt signaling along with other as-yet-unknown changes that drive oncogenesis. We used this Drosophila glioblastoma model to perform a kinome-wide genetic screen for new genes required for RTK- and PI3K-dependent neoplastic transformation. Human orthologs of novel kinases uncovered by these screens were functionally assessed in mammalian glioblastoma models and human tumors. Our results revealed that the atypical kinases RIOK1 and RIOK2 are overexpressed in glioblastoma cells in an Akt-dependent manner. Moreover, we found that overexpressed RIOK2 formed a complex with RIOK1, mTor, and mTor-complex-2 components, and that overexpressed RIOK2 upregulated Akt signaling and promoted tumorigenesis in murine astrocytes. Conversely, reduced expression of RIOK1 or RIOK2 disrupted Akt signaling and caused cell cycle exit, apoptosis, and chemosensitivity in glioblastoma cells by inducing p53 activity through the RpL11-dependent ribosomal stress checkpoint. These results imply that, in glioblastoma cells, constitutive Akt signaling drives RIO kinase overexpression, which creates a feedforward loop that promotes and maintains oncogenic Akt activity through stimulation of mTor signaling. Further study of the RIO kinases as well as other kinases identified in our Drosophila screen may reveal new insights into defects underlying glioblastoma and related cancers and may reveal new therapeutic opportunities for these cancers.

  6. Evaluation by biodistribution of two anti-peptidoglycan aptamers labeled with Technetium-{sup 99m} for in vivo bacterial infection identification

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Iêda M.; Lacerda, Camila M.S.; Santos, Sara R.; Andrade, Antero S.R. de, E-mail: imendesf@yahoo.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Fernandes, Simone O.; Barros, André B. de; Cardoso, Valbert N., E-mail: valbertcardoso@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Análises Clínicas e Toxicológicas

    2017-07-01

    Nuclear medicine clinics are still awaiting optimal scintigraphic imaging agents capable of discriminating between infection and inflammation, and between fungal and bacterial infections. Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. In the present study, two aptamers for peptidoglycan (termed Antibac1 and Antibac2) were labeled with {sup 99m}Tc and evaluated for bacterial infection identification by biodistribution. The direct labeling method with {sup 99m}Tc allowed radiolabel yields higher than 90% and the complexes were stable in saline, plasma and cysteine excess. The {sup 99m}Tc-Antibac1 in the group infected with S. aureus presented a target/non-target ratio (T/NT) of 2.81 ± 0.67, significantly higher than verified for the {sup 99m}Tc-library (control): 1.52 ± 0.07. A radiolabeled library of oligonucleotides with random sequences was used as a control for monitoring nonspecific uptake at the site of infection. In the model with C. albicans infection the T/NT ratio for {sup 99m}Tc-Antibac1 was 1.46 ± 0.11, similar that obtained for the {sup 99m}Tc-library in the same model: 1.52 ± 0.05. The {sup 99m}Tc-Antibac2 in the group infected with S. aureus showed a T/NT ratio of 2.61 ± 0.66, statistically higher than achieved for the {sup 99m}Tc-library: 1.52 ± 0.07. In the group infected with C. albicans this ratio for {sup 99m}Tc-Antibac2 was 1.75 ± 0.19, also statistically higher in relation to the {sup 99m}Tc-library: 1.52 ± 0.05. Both aptamers were effective in identifying bacterial infection foci, but only {sup 99m}Tc-Antibac1 showed no cross reactivity for fungal cells. (author)

  7. Incidence and predictors of hospitalization for bacterial infection in community-based patients with type 2 diabetes: the fremantle diabetes study.

    Directory of Open Access Journals (Sweden)

    Emma J Hamilton

    Full Text Available BACKGROUND: The few studies that have examined the relationship between diabetes and bacterial infections have utilized administrative databases and/or have had limited/incomplete data including recognized infection risk factors. The aim of this study was to determine the incidence and associates of bacterial infection severe enough to require hospitalization in well-characterized community-based patients with type 2 diabetes. METHODS AND FINDINGS: We studied a cohort of 1,294 patients (mean±SD age 64.1±11.3 years from the longitudinal observational Fremantle Diabetes Study Phase I (FDS1 and 5,156 age-, gender- and zip-code-matched non-diabetic controls. The main outcome measure was incident hospitalization for bacterial infection as principal diagnosis between 1993 and 2010. We also examined differences in statin use in 52 FDS1 pairs hospitalized with pneumonia (cases or a contemporaneous non-infection-related cause (controls. During 12.0±5.4 years of follow-up, 251 (19.4% patients were hospitalized on 368 occasions for infection (23.7/1,000 patient-years. This was more than double the rate in matched controls (incident rate ratio (IRR (95% CI, 2.13 (1.88-2.42, P<0.001. IRRs for pneumonia, cellulitis, and septicemia/bacteremia were 1.86 (1.55-2.21, 2.45 (1.92-3.12, and 2.08 (1.41-3.04, respectively (P<0.001. Among the diabetic patients, older age, male sex, prior recent infection-related hospitalization, obesity, albuminuria, retinopathy and Aboriginal ethnicity were baseline variables independently associated with risk of first hospitalization with any infection (P≤0.005. After adjustment for these variables, baseline statin treatment was not significant (hazard ratio (95% CI, 0.70 (0.39-1.25, P = 0.22. Statin use at hospitalization for pneumonia among the case-control pairs was similar (23.1% vs. 13.5%, P = 0.27. CONCLUSIONS: The risk of severe infection is increased among type 2 diabetic patients and is not reduced by statin

  8. Genome-wide siRNA Screening at Biosafety Level 4 Reveals a Crucial Role for Fibrillarin in Henipavirus Infection.

    Directory of Open Access Journals (Sweden)

    Celine Deffrasnes

    2016-03-01

    Full Text Available Hendra and Nipah viruses (genus Henipavirus, family Paramyxoviridae are highly pathogenic bat-borne viruses. The need for high biocontainment when studying henipaviruses has hindered the development of therapeutics and knowledge of the viral infection cycle. We have performed a genome-wide siRNA screen at biosafety level 4 that identified 585 human proteins required for henipavirus infection. The host protein with the largest impact was fibrillarin, a nucleolar methyltransferase that was also required by measles, mumps and respiratory syncytial viruses for infection. While not required for cell entry, henipavirus RNA and protein syntheses were greatly impaired in cells lacking fibrillarin, indicating a crucial role in the RNA replication phase of infection. During infection, the Hendra virus matrix protein co-localized with fibrillarin in cell nucleoli, and co-associated as a complex in pulldown studies, while its nuclear import was unaffected in fibrillarin-depleted cells. Mutagenesis studies showed that the methyltransferase activity of fibrillarin was required for henipavirus infection, suggesting that this enzyme could be targeted therapeutically to combat henipavirus infections.

  9. A targeted glycan-related gene screen reveals heparan sulfate proteoglycan sulfation regulates WNT and BMP trans-synaptic signaling.

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    Neil Dani

    Full Text Available A Drosophila transgenic RNAi screen targeting the glycan genome, including all N/O/GAG-glycan biosynthesis/modification enzymes and glycan-binding lectins, was conducted to discover novel glycan functions in synaptogenesis. As proof-of-product, we characterized functionally paired heparan sulfate (HS 6-O-sulfotransferase (hs6st and sulfatase (sulf1, which bidirectionally control HS proteoglycan (HSPG sulfation. RNAi knockdown of hs6st and sulf1 causes opposite effects on functional synapse development, with decreased (hs6st and increased (sulf1 neurotransmission strength confirmed in null mutants. HSPG co-receptors for WNT and BMP intercellular signaling, Dally-like Protein and Syndecan, are differentially misregulated in the synaptomatrix of these mutants. Consistently, hs6st and sulf1 nulls differentially elevate both WNT (Wingless; Wg and BMP (Glass Bottom Boat; Gbb ligand abundance in the synaptomatrix. Anterograde Wg signaling via Wg receptor dFrizzled2 C-terminus nuclear import and retrograde Gbb signaling via synaptic MAD phosphorylation and nuclear import are differentially activated in hs6st and sulf1 mutants. Consequently, transcriptional control of presynaptic glutamate release machinery and postsynaptic glutamate receptors is bidirectionally altered in hs6st and sulf1 mutants, explaining the bidirectional change in synaptic functional strength. Genetic correction of the altered WNT/BMP signaling restores normal synaptic development in both mutant conditions, proving that altered trans-synaptic signaling causes functional differentiation defects.

  10. A genome-wide RNAi screen reveals MAP kinase phosphatases as key ERK pathway regulators during embryonic stem cell differentiation.

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    Shen-Hsi Yang

    Full Text Available Embryonic stem cells and induced pluripotent stem cells represent potentially important therapeutic agents in regenerative medicine. Complex interlinked transcriptional and signaling networks control the fate of these cells towards maintenance of pluripotency or differentiation. In this study we have focused on how mouse embryonic stem cells begin to differentiate and lose pluripotency and, in particular, the role that the ERK MAP kinase and GSK3 signaling pathways play in this process. Through a genome-wide siRNA screen we have identified more than 400 genes involved in loss of pluripotency and promoting the onset of differentiation. These genes were functionally associated with the ERK and/or GSK3 pathways, providing an important resource for studying the roles of these pathways in controlling escape from the pluripotent ground state. More detailed analysis identified MAP kinase phosphatases as a focal point of regulation and demonstrated an important role for these enzymes in controlling ERK activation kinetics and subsequently determining early embryonic stem cell fate decisions.

  11. Validation of FRET Assay for the Screening of Growth Inhibitors of Escherichia coli Reveals Elongasome Assembly Dynamics

    Science.gov (United States)

    van der Ploeg, René; Goudelis, Spyridon Theodoros; den Blaauwen, Tanneke

    2015-01-01

    The increase in antibiotic resistant bacteria demands the development of new antibiotics against preferably new targets. The common approach is to test compounds for their ability to kill bacteria or to design molecules that inhibit essential protein activities in vitro. In the first case, the mode of action of the drug is unknown and in the second case, it is not known whether the compound will pass the impermeable barrier of the bacterial envelope. We developed an assay that detects the target of a compound, as well as its ability to pass the membrane(s) simultaneously. The Escherichia coli cytoskeletal protein MreB recruits protein complexes (elongasomes) that are essential for cell envelope growth. An in cell Förster Resonance Energy Transfer (FRET) assay was developed to detect the interaction between MreB molecules and between MreB and the elongasome proteins RodZ, RodA and PBP2. Inhibition of the polymerization of MreB by S-(3,4-dichlorobenzyl) isothiourea (A22) or of the activity of PBP2 by mecilinam resulted in loss or reduction of all measured interactions. This suggests that the interactions between the elongasome proteins are governed by a combination of weak affinities and substrate availability. This validated in cell FRET assay can be used to screen for cell envelope growth inhibitors. PMID:26263980

  12. Validation of FRET Assay for the Screening of Growth Inhibitors of Escherichia coli Reveals Elongasome Assembly Dynamics

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    René van der Ploeg

    2015-07-01

    Full Text Available The increase in antibiotic resistant bacteria demands the development of new antibiotics against preferably new targets. The common approach is to test compounds for their ability to kill bacteria or to design molecules that inhibit essential protein activities in vitro. In the first case, the mode of action of the drug is unknown and in the second case, it is not known whether the compound will pass the impermeable barrier of the bacterial envelope. We developed an assay that detects the target of a compound, as well as its ability to pass the membrane(s simultaneously. The Escherichia coli cytoskeletal protein MreB recruits protein complexes (elongasomes that are essential for cell envelope growth. An in cell Förster Resonance Energy Transfer (FRET assay was developed to detect the interaction between MreB molecules and between MreB and the elongasome proteins RodZ, RodA and PBP2. Inhibition of the polymerization of MreB by S-(3,4-dichlorobenzyl isothiourea (A22 or of the activity of PBP2 by mecilinam resulted in loss or reduction of all measured interactions. This suggests that the interactions between the elongasome proteins are governed by a combination of weak affinities and substrate availability. This validated in cell FRET assay can be used to screen for cell envelope growth inhibitors.

  13. Mutational screening of the USH2A gene in Spanish USH patients reveals 23 novel pathogenic mutations

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    Diaz-Llopis Manuel

    2011-10-01

    Full Text Available Abstract Background Usher Syndrome type II (USH2 is an autosomal recessive disorder, characterized by moderate to severe hearing impairment and retinitis pigmentosa (RP. Among the three genes implicated, mutations in the USH2A gene account for 74-90% of the USH2 cases. Methods To identify the genetic cause of the disease and determine the frequency of USH2A mutations in a cohort of 88 unrelated USH Spanish patients, we carried out a mutation screening of the 72 coding exons of this gene by direct sequencing. Moreover, we performed functional minigene studies for those changes that were predicted to affect splicing. Results As a result, a total of 144 DNA sequence variants were identified. Based upon previous studies, allele frequencies, segregation analysis, bioinformatics' predictions and in vitro experiments, 37 variants (23 of them novel were classified as pathogenic mutations. Conclusions This report provide a wide spectrum of USH2A mutations and clinical features, including atypical Usher syndrome phenotypes resembling Usher syndrome type I. Considering only the patients clearly diagnosed with Usher syndrome type II, and results obtained in this and previous studies, we can state that mutations in USH2A are responsible for 76.1% of USH2 disease in patients of Spanish origin.

  14. A screen for constituents of motor control and decision making in Drosophila reveals visual distance-estimation neurons

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    Triphan, Tilman; Nern, Aljoscha; Roberts, Sonia F.; Korff, Wyatt; Naiman, Daniel Q.; Strauss, Roland

    2016-01-01

    Climbing over chasms larger than step size is vital to fruit flies, since foraging and mating are achieved while walking. Flies avoid futile climbing attempts by processing parallax-motion vision to estimate gap width. To identify neuronal substrates of climbing control, we screened a large collection of fly lines with temporarily inactivated neuronal populations in a novel high-throughput assay described here. The observed climbing phenotypes were classified; lines in each group are reported. Selected lines were further analysed by high-resolution video cinematography. One striking class of flies attempts to climb chasms of unsurmountable width; expression analysis guided us to C2 optic-lobe interneurons. Inactivation of C2 or the closely related C3 neurons with highly specific intersectional driver lines consistently reproduced hyperactive climbing whereas strong or weak artificial depolarization of C2/C3 neurons strongly or mildly decreased climbing frequency. Contrast-manipulation experiments support our conclusion that C2/C3 neurons are part of the distance-evaluation system. PMID:27255169

  15. Novel insights in preventing Gram-negative bacterial infection in cirrhotic patients: review on the effects of GM-CSF in maintaining homeostasis of the immune system.

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    Xu, Dong; Zhao, Manzhi; Song, Yuhu; Song, Jianxin; Huang, Yuancheng; Wang, Junshuai

    2015-01-01

    Cirrhotic patients with dysfunctional and/or low numbers of leukocytes are often infected with bacteria, especially Gram-negative bacteria, which is characterized by producing lipopolysaccharide (LPS). Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a pleiotropic cytokine that influences the production, maturation, function, and survival of various immune cells. In this paper, we reviewed not only Toll-like receptors 4 (TLR4) signaling pathway and its immunological effect, but also the specific stimulating function and autocrine performance of GM-CSF on hematopoietic cells, as well as the recent discovery of innate response activator-B cells in protection against microbial sepsis and the direct LPS-TLR4 signaling on hematopoiesis. Thus we concluded that GM-CSF might play important roles in preventing Gram-negative bacterial infections in cirrhotic patients through maintaining immune system functions and homeostasis.

  16. A functional microRNA library screen reveals miR-410 as a novel anti-apoptotic regulator of cholangiocarcinoma

    International Nuclear Information System (INIS)

    Palumbo, Tiziana; Poultsides, George A.; Kouraklis, Grigorios; Liakakos, Theodore; Drakaki, Alexandra; Peros, George; Hatziapostolou, Maria; Iliopoulos, Dimitrios

    2016-01-01

    Cholangiocarcinoma is characterized by late diagnosis and a poor survival rate. MicroRNAs have been involved in the pathogenesis of different cancer types, including cholangiocarcinoma. Our aim was to identify novel microRNAs regulating cholangiocarcinoma cell growth in vitro and in vivo. A functional microRNA library screen was performed in human cholangiocarcinoma cells to identify microRNAs that regulate cholangiocarcinoma cell growth. Real-time PCR analysis evaluated miR-9 and XIAP mRNA levels in cholangiocarcinoma cells and tumors. The screen identified 21 microRNAs that regulated >50 % cholangiocarcinoma cell growth. MiR-410 was identified as the top suppressor of growth, while its overexpression significantly inhibited the invasion and colony formation ability of cholangiocarcinoma cells. Bioinformatics analysis revealed that microRNA-410 exerts its effects through the direct regulation of the X-linked inhibitor of apoptosis protein (XIAP). Furthermore, overexpression of miR-410 significantly reduced cholangiocarcinoma tumor growth in a xenograft mouse model through induction of apoptosis. In addition, we identified an inverse relationship between miR-410 and XIAP mRNA levels in human cholangiocarcinomas. Taken together, our study revealed a novel microRNA signaling pathway involved in cholangiocarcinoma and suggests that manipulation of the miR-410/XIAP pathway could have a therapeutic potential for cholangiocarcinoma. The online version of this article (doi:10.1186/s12885-016-2384-0) contains supplementary material, which is available to authorized users

  17. RNAi screen reveals a role of SPHK2 in dengue virus-mediated apoptosis in hepatic cell lines.

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    Atthapan Morchang

    Full Text Available Hepatic dysfunction is a feature of dengue virus (DENV infection. Hepatic biopsy specimens obtained from fatal cases of DENV infection show apoptosis, which relates to the pathogenesis of DENV infection. However, how DENV induced liver injury is not fully understood. In this study, we aim to identify the factors that influence cell death by employing an apoptosis-related siRNA library screening. Our results show the effect of 558 gene silencing on caspase 3-mediated apoptosis in DENV-infected Huh7 cells. The majority of genes that contributed to apoptosis were the apoptosis-related kinase enzymes. Tumor necrosis factor superfamily member 12 (TNFSF12, and sphingosine kinase 2 (SPHK2, were selected as the candidate genes to further validate their influences on DENV-induced apoptosis. Transfection of siRNA targeting SPHK2 but not TNFSF12 genes reduced apoptosis determined by Annexin V/PI staining. Knockdown of SPHK2 did not reduce caspase 8 activity; however, did significantly reduce caspase 9 activity, suggesting its involvement of SPHK2 in the intrinsic pathway of apoptosis. Treatment of ABC294649, an inhibitor of SPHK2, reduced the caspase 3 activity, suggesting the involvement of its kinase activity in apoptosis. Knockdown of SPHK2 significantly reduced caspase 3 activity not only in DENV-infected Huh7 cells but also in DENV-infected HepG2 cells. Our results were consistent across all of the four serotypes of DENV infection, which supports the pro-apoptotic role of SPHK2 in DENV-infected liver cells.

  18. An EST screen from the annelid Pomatoceros lamarckii reveals patterns of gene loss and gain in animals

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    Chen Wei-Chung

    2009-09-01

    Full Text Available Abstract Background Since the drastic reorganisation of the phylogeny of the animal kingdom into three major clades of bilaterians; Ecdysozoa, Lophotrochozoa and Deuterostomia, it became glaringly obvious that the selection of model systems with extensive molecular resources was heavily biased towards only two of these three clades, namely the Ecdysozoa and Deuterostomia. Increasing efforts have been put towards redressing this imbalance in recent years, and one of the principal phyla in the vanguard of this endeavour is the Annelida. Results In the context of this effort we here report our characterisation of an Expressed Sequence Tag (EST screen in the serpulid annelid, Pomatoceros lamarckii. We have sequenced over 5,000 ESTs which consolidate into over 2,000 sequences (clusters and singletons. These sequences are used to build phylogenetic trees to estimate relative branch lengths amongst different taxa and, by comparison to genomic data from other animals, patterns of gene retention and loss are deduced. Conclusion The molecular phylogenetic trees including the P. lamarckii sequences extend early observations that polychaetes tend to have relatively short branches in such trees, and hence are useful taxa with which to reconstruct gene family evolution. Also, with the availability of lophotrochozoan data such as that of P. lamarckii, it is now possible to make much more accurate reconstructions of the gene complement of the ancestor of the bilaterians than was previously possible from comparisons of ecdysozoan and deuterostome genomes to non-bilaterian outgroups. It is clear that the traditional molecular model systems for protostomes (e.g. Drosophila melanogaster and Caenorhabditis elegans, which are restricted to the Ecdysozoa, have undergone extensive gene loss during evolution. These ecdysozoan systems, in terms of gene content, are thus more derived from the bilaterian ancestral condition than lophotrochozoan systems like the polychaetes

  19. Targeted Genetic Screen in Amyotrophic Lateral Sclerosis Reveals Novel Genetic Variants with Synergistic Effect on Clinical Phenotype

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    Johnathan Cooper-Knock

    2017-11-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is underpinned by an oligogenic rare variant architecture. Identified genetic variants of ALS include RNA-binding proteins containing prion-like domains (PrLDs. We hypothesized that screening genes encoding additional similar proteins will yield novel genetic causes of ALS. The most common genetic variant of ALS patients is a G4C2-repeat expansion within C9ORF72. We have shown that G4C2-repeat RNA sequesters RNA-binding proteins. A logical consequence of this is that loss-of-function mutations in G4C2-binding partners might contribute to ALS pathogenesis independently of and/or synergistically with C9ORF72 expansions. Targeted sequencing of genomic DNA encoding either RNA-binding proteins or known ALS genes (n = 274 genes was performed in ALS patients to identify rare deleterious genetic variants and explore genotype-phenotype relationships. Genomic DNA was extracted from 103 ALS patients including 42 familial ALS patients and 61 young-onset (average age of onset 41 years sporadic ALS patients; patients were chosen to maximize the probability of identifying genetic causes of ALS. Thirteen patients carried a G4C2-repeat expansion of C9ORF72. We identified 42 patients with rare deleterious variants; 6 patients carried more than one variant. Twelve mutations were discovered in known ALS genes which served as a validation of our strategy. Rare deleterious variants in RNA-binding proteins were significantly enriched in ALS patients compared to control frequencies (p = 5.31E-18. Nineteen patients featured at least one variant in a RNA-binding protein containing a PrLD. The number of variants per patient correlated with rate of disease progression (t-test, p = 0.033. We identified eighteen patients with a single variant in a G4C2-repeat binding protein. Patients with a G4C2-binding protein variant in combination with a C9ORF72 expansion had a significantly faster disease course (t-test, p = 0.025. Our data are

  20. Transcriptomic profiling-based mutant screen reveals three new transcription factors mediating menadione resistance in Neurospora crassa.

    Science.gov (United States)

    Zhu, Jufen; Yu, Xinxu; Xie, Baogui; Gu, Xiaokui; Zhang, Zhenying; Li, Shaojie

    2013-06-01

    To gain insight into the regulatory mechanisms of oxidative stress responses in filamentous fungi, the genome-wide transcriptional response of Neurospora crassa to menadione was analysed by digital gene expression (DGE) profiling, which identified 779 upregulated genes and 576 downregulated genes. Knockout mutants affecting 130 highly-upregulated genes were tested for menadione sensitivity, which revealed that loss of the transcription factor siderophore regulation (SRE) (a transcriptional repressor for siderophore biosynthesis), catatase-3, cytochrome c peroxidase or superoxide dismutase 1 copper chaperone causes hypersensitivity to menadione. Deletion of sre dramatically increased transcription of the siderophore biosynthesis gene ono and the siderophore iron transporter gene sit during menadione stress, suggesting that SRE is required for repression of iron uptake under oxidative stress conditions. Contrary to its phenotype, the sre deletion mutant showed higher transcriptional levels of genes encoding reactive oxygen species (ROS) scavengers than wild type during menadione stress, which implies that the mutant suffers a higher level of oxidative stress than wild type. Uncontrolled iron uptake in the sre mutant might exacerbate cellular oxidative stress. This is the first report of a negative regulator of iron assimilation participating in the fungal oxidative stress response. In addition to SRE, eight other transcription factor genes were also menadione-responsive but their single gene knockout mutants showed wild-type menadione sensitivity. Two of them, named as mit-2 (menadione induced transcription factor-2) and mit-4 (menadione induced transcription factor-4), were selected for double mutant analysis. The double mutant was hypersensitive to menadione. Similarly, the double mutation of mit-2 and sre also had additive effects on menadione sensitivity, suggesting multiple transcription factors mediate oxidative stress resistance in an additive manner

  1. A Genetic Screen Reveals that Synthesis of 1,4-Dihydroxy-2-Naphthoate (DHNA), but Not Full-Length Menaquinone, Is Required for Listeria monocytogenes Cytosolic Survival.

    Science.gov (United States)

    Chen, Grischa Y; McDougal, Courtney E; D'Antonio, Marc A; Portman, Jonathan L; Sauer, John-Demian

    2017-03-21

    Through unknown mechanisms, the host cytosol restricts bacterial colonization; therefore, only professional cytosolic pathogens are adapted to colonize this host environment. Listeria monocytogenes is a Gram-positive intracellular pathogen that is highly adapted to colonize the cytosol of both phagocytic and nonphagocytic cells. To identify L. monocytogenes determinants of cytosolic survival, we designed and executed a novel screen to isolate L. monocytogenes mutants with cytosolic survival defects. Multiple mutants identified in the screen were defective for synthesis of menaquinone (MK), an essential molecule in the electron transport chain. Analysis of an extensive set of MK biosynthesis and respiratory chain mutants revealed that cellular respiration was not required for cytosolic survival of L. monocytogenes but that, instead, synthesis of 1,4-dihydroxy-2-naphthoate (DHNA), an MK biosynthesis intermediate, was essential. Recent discoveries showed that modulation of the central metabolism of both host and pathogen can influence the outcome of host-pathogen interactions. Our results identify a potentially novel function of the MK biosynthetic intermediate DHNA and specifically highlight how L. monocytogenes metabolic adaptations promote cytosolic survival and evasion of host immunity. IMPORTANCE Cytosolic bacterial pathogens, such as Listeria monocytogenes and Francisella tularensis , are exquisitely evolved to colonize the host cytosol in a variety of cell types. Establishing an intracellular niche shields these pathogens from effectors of humoral immunity, grants access to host nutrients, and is essential for pathogenesis. Through yet-to-be-defined mechanisms, the host cytosol restricts replication of non-cytosol-adapted bacteria, likely through a combination of cell autonomous defenses (CADs) and nutritional immunity. Utilizing a novel genetic screen, we identified determinants of L. monocytogenes cytosolic survival and virulence and identified a role

  2. Genome-wide CRISPR-Cas9 Screens Reveal Loss of Redundancy between PKMYT1 and WEE1 in Glioblastoma Stem-like Cells

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    Chad M. Toledo

    2015-12-01

    Full Text Available To identify therapeutic targets for glioblastoma (GBM, we performed genome-wide CRISPR-Cas9 knockout (KO screens in patient-derived GBM stem-like cells (GSCs and human neural stem/progenitors (NSCs, non-neoplastic stem cell controls, for genes required for their in vitro growth. Surprisingly, the vast majority GSC-lethal hits were found outside of molecular networks commonly altered in GBM and GSCs (e.g., oncogenic drivers. In vitro and in vivo validation of GSC-specific targets revealed several strong hits, including the wee1-like kinase, PKMYT1/Myt1. Mechanistic studies demonstrated that PKMYT1 acts redundantly with WEE1 to inhibit cyclin B-CDK1 activity via CDK1-Y15 phosphorylation and to promote timely completion of mitosis in NSCs. However, in GSCs, this redundancy is lost, most likely as a result of oncogenic signaling, causing GBM-specific lethality.

  3. Infecções bacterianas pioram o prognóstico da hepatite alcoólica Alcoholic hepatitis: bad prognosis due to concomitant bacterial infections

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    Edna Strauss

    2004-06-01

    Full Text Available As infecções bacterianas cursam com altos índices de morbilidade e mortalidade na cirrose hepática. O objetivo do nosso trabalho foi avaliar se também na hepatite alcoólica as infecções bacterianas são fatores de mau prognóstico. Na avaliação retrospectiva de 681 pacientes hospitalizados em um único centro, por período de 6 anos, foram bem documentados 52 (7,5% casos de hepatite alcoólica, sendo 73,1% com biópsia hepática para análise histopatológica e os restantes por diagnóstico clínico-bioquímico. Houve predomínio do sexo masculino (relação 3,3:1,0, com idade média de 40 anos e ingestão média de etanol puro de 193g/dia por mais de 3 anos. As principais complicações foram: encefalopatia hepática (n=5, insuficiência renal (n=4 e hemorragia digestiva alta (n=3. Houve infecção bacteriana em 11 (21,1% pacientes, sendo pulmonar (n=5, peritonite bacteriana espontânea (PBE (n=2, urinária (n=3 e dermatológica (n=1. Óbito precoce, durante o período de internação ocorreu em 8 (15,4% casos e a análise comparativa entre eles e os sobreviventes mostrou serem fatores de mau prognóstico a presença de encefalopatia hepática (p=0,012, bilirrubinas > 20mg% (p=0,012 e associação com infecções graves (pulmonar/PBE, com p=0,004. Em conclusão, demonstramos que as infecções bacterianas são fatores de mau prognóstico na hepatite alcoólica. Recomendamos, portanto, que a profilaxia com antibióticos que se faz durante hemorragia digestiva alta na cirrose e em casos de insuficiência hepática fulminante, seja estendida para a hepatite alcoólica, em sua forma grave, com finalidade de evitar infecções bacterianas e mortalidade precoce.Bacterial infections increase morbidity and mortality in cirrhosis. Our aim was to investigate whether in alcoholic hepatitis the development of bacterial infections was also a poor prognostic factor. In the retrospective evaluation of 681 hospitalized patients with liver disease

  4. Biomarker screening of oral cancer cell lines revealed sub-populations of CD133-, CD44-, CD24- and ALDH1- positive cancer stem cells

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    Kendall K

    2013-05-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC ranks sixth worldwide for cancer-related mortality. For the past several decades the mainstay of treatment for HNSCC has been surgery and external beam radiation, although more recent trials combining chemotherapy and radiation have demonstrated improvements. However, cancer recurrence and treatment failures continue to occur in a significant percentage of patients. Recent advances in tumor biology have led to the discovery that many cancers, including HNSCC, may contain subpopulations of cells with stem cell-like properties that may explain relapse and recurrence. The objective of this study was to screen existing oral cancer cell lines for biomarkers specific for cells with stem cell-like properties. RNA was isolated for RT-PCR screening using primers for specific mRNA of the biomarkers: CD44, CD24, CD133, NANOG, Nestin, ALDH1, and ABCG2 in CAL27, SCC25 and SCC15 cells. This analysis revealed that some oral cancer cell lines (CAL27 and SCC25 may contain small subpopulations of adhesion- and contact-independent cells (AiDC that also express tumor stem cell markers, including CD44, CD133, and CD24. In addition, CAL27 cells also expressed the intracellular tumor stem cell markers, ALDH1 and ABCG2. Isolation and culture of the adhesion- and contact-independent cells from CAL27 and SCC25 populations revealed differential proliferation rates and more robust inhibition by the MEK inhibitor PD98059, as well as the chemotherapeutic agents Cisplatin and Paclitaxel, within the AiDC CAL27 cells. At least one oral cancer cell line (CAL27 contained subpopulations of cells that express specific biomarkers associated with tumor stem cells which were morphologically and phenotypically distinct from other cells within this cell line.

  5. A cysteine protease (cathepsin Z) from disk abalone, Haliotis discus discus: Genomic characterization and transcriptional profiling during bacterial infections.

    Science.gov (United States)

    Godahewa, G I; Perera, N C N; Lee, Sukkyoung; Kim, Myoung-Jin; Lee, Jehee

    2017-09-05

    Cathepsin Z (CTSZ) is lysosomal cysteine protease of the papain superfamily. It participates in the host immune defense via phagocytosis, signal transduction, cell-cell communication, proliferation, and migration of immune cells such as monocytes, macrophages, and dendritic cells. Hence, CTSZ is also acknowledged as an acute-phase protein in host immunity. In this study, we sought to identify the CTSZ homolog from disk abalone (AbCTSZ) and characterize it at the molecular, genomic, and transcriptional levels. AbCTSZ encodes a protein with 318 amino acids and a molecular mass of 36kDa. The structure of AbCTSZ reveals amino acid sequences that are characteristic of the signal sequence, pro-peptide, peptidase-C1 papain family cysteine protease domain, mini-loop, HIP motif, N-linked glycosylation sites, active sites, and conserved Cys residues. A pairwise comparison revealed that AbCTSZ shared the highest amino acid homology with its molluscan counterpart from Crassostrea gigas. A multiple alignment analysis revealed the conservation of functionally crucial elements of AbCTSZ, and a phylogenetic study further confirmed a proximal evolutionary relationship with its invertebrate counterparts. Further, an analysis of AbCTSZ genomic structure revealed seven exons separated by six introns, which differs from that of its vertebrate counterparts. Quantitative real time PCR (qPCR) detected the transcripts of AbCTSZ in early developmental stages and in eight different tissues. Higher levels of AbCTSZ transcripts were found in trochophore, gill, and hemocytes, highlighting its importance in the early development and immunity of disk abalone. In addition, we found that viable bacteria (Vibrio parahaemolyticus and Listeria monocytogenes) and bacterial lipopolysaccharides significantly modulated AbCTSZ transcription. Collectively, these lines of evidences suggest that AbCTSZ plays an indispensable role in the innate immunity of disk abalone. Copyright © 2017. Published by Elsevier

  6. Mixed metazoan and bacterial infection of the gas bladder of the lined seahorse-a case report.

    Science.gov (United States)

    Anderson, Paul A; Petty, Barbara D

    2013-03-01

    Five wild-caught Lined Seahorses Hippocampus erectus from an aquarium system presented with altered buoyancy and distended upper trunks. Radiography of one specimen revealed a reduced air volume in the gas bladder. Pneumocystocentesis revealed a brown exudate of numerous leukocytes, parasite ova, and Gram- and acid-fast-positive bacilli under wet mounts and stains. Necropsies revealed enlarged, friable kidneys and distended gas bladders containing copious purulent exudate, necrotic tissue, and adult digeneans Dictysarca virens. Bacterial isolates from exudate cultures grown on Lowenstein-Jensen medium were identified as Gordonia sp. and Mycobacterium poriferae by high-performance liquid chromatography and 16S ribosomal DNA sequencing. Histopathology demonstrated a histiocytic response in kidney and gas bladder exudate, inflammation of the gas bladder wall, and infection of the gas bladder lumen with parasite ova and acid-fast-positive and Gomori's methenamine silver-positive bacilli. Praziquantel is prescribed for digenean infections but dissolves incompletely in seawater and is toxic to this host. Eradication of intermediate host vectors is a management option. Treatment of Gordonia infection has not been addressed in nonhuman animals, and there is no known effective treatment for Mycobacterium spp. infection in fishes. This is the first case report of digenean infection of the gas bladder in a syngnathid, Gordonia sp. infection in a nonhuman animal, and M. poriferae infection in a fish.

  7. Prevalence of Escherichia coli O157:H7 Bacterial Infections Associated With the Use of Animal Wastes in Louisiana for the Period 1996-2004

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    Paul B. Tchounwou

    2006-03-01

    Full Text Available Animal waste from dairy and poultry operations is an economical and commonly used fertilizer in the state of Louisiana. The application of animal waste to pasture lands not only is a source of fertilizer, but also allows for a convenient method of waste disposal. The disposal of animal wastes on land is a potential non-point source of water degradation. Human health is a major concern when considering the disposal of large quantities of animal waste. Health concerns could exist from exposure to pathogens and excess nitrogen associated with this form of pollution. The objective of this study was to collect and analyze health data related to Escherichia coli O157:H7 bacterial infections associated with the use of animal waste in Louisiana for the years 1996-2004. An analysis of adverse health effects associated with the use of animal waste in Louisiana was conducted based on the incidence/prevalence rate for the studied years. The number of reported cases increased during the summer months. Analysis of health data of the studied years showed that the number of reported disease cases of E. coli O157:H7 were highest among Caucasian infants in the 0-4 year old age category and in Caucasian children in the 5-9 year old age category. Although the number of cases declined with age, a slight increase in rates was seen among the elderly population. While the rate of reported cases per 100,000 people remained the same for the years of 1999 and 2000, the rate decreased by 60% from the year 2000 to 2001. A slight decline of the number of cases that was also reported for the years 2002 and 2003. The high rate of identification in the younger population may result from the prompt seeking of medical care when symptoms become evident among infants and young children as well as the frequent ordering of stool examination when symptoms become evident in this population group. It was also noted that areas that had a higher number of reported cases also had a greater

  8. 17Beta-estradiol affects the response of complement components and survival of rainbow trout (Oncorhynchus mykiss) challenged by bacterial infection.

    Science.gov (United States)

    Wenger, Michael; Sattler, Ursula; Goldschmidt-Clermont, Elinor; Segner, Helmut

    2011-07-01

    Research on the endocrine role of estrogens has focused on the reproductive system, while other potential target systems have been less studied. Here, we investigated the possible immunomodulating role of 17β-estradiol (E2) using rainbow trout (Oncorhynchus mykiss) as a model. The aims of the study were to examine a) whether estrogens can modulate immune gene transcription levels, and b) whether this has functional implications for the resistance of trout towards pathogens. Trout were reared from fertilization until 6 months of age under (1) control conditions, (2) short-term E2-treatment (6-month-old juveniles were fed a diet containing 20 mg E2/kg for 2 weeks), or c) long-term E2-treatment (twice a 2-h-bath-exposure of trout embryos to 400 μg 17β-estradiol (E2)/L, followed by rearing on the E2-spiked diet from start-feeding until 6 months of age). Analysis of plasma estrogen levels indicated that the internal estrogen concentrations of E2-exposed fish were within the physiological range and analysis of hepatic vitellogenin mRNA levels indicated that the E2 administration was effective in activating the endogenous estrogen receptor pathway. However, expression levels of the hepatic complement components C3-1, C3-3, and Factor H were not affected by E2-treatment. In a next step, 6-month-old juveniles were challenged with pathogenic bacteria (Yersinia ruckeri). In control fish, this bacterial infection resulted in significant up-regulation of the mRNA levels of hepatic complement genes (C3-1, C3-3, Factor B, Factor H), while E2-treated fish showed no or significantly lower up-regulation of the complement gene transcription levels. Apparently, the E2-treated trout had a lower capacity to activate their immune system to defend against the bacterial infection. This interpretation is corroborated by the finding that survival of E2-treated fish under bacterial challenge was significantly lower than in the control group. In conclusion, the results from this study

  9. Functional microRNA high throughput screening reveals miR-9 as a central regulator of liver oncogenesis by affecting the PPARA-CDH1 pathway

    International Nuclear Information System (INIS)

    Drakaki, Alexandra; Hatziapostolou, Maria; Polytarchou, Christos; Vorvis, Christina; Poultsides, George A.; Souglakos, John; Georgoulias, Vassilis; Iliopoulos, Dimitrios

    2015-01-01

    Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths, reflecting the aggressiveness of this type of cancer and the absence of effective therapeutic regimens. MicroRNAs have been involved in the pathogenesis of different types of cancers, including liver cancer. Our aim was to identify microRNAs that have both functional and clinical relevance in HCC and examine their downstream signaling effectors. MicroRNA and gene expression levels were measured by quantitative real-time PCR in HCC tumors and controls. A TargetScan algorithm was used to identify miR-9 downstream direct targets. A high-throughput screen of the human microRNAome revealed 28 microRNAs as regulators of liver cancer cell invasiveness. MiR-9, miR-21 and miR-224 were the top inducers of HCC invasiveness and also their expression was increased in HCC relative to control liver tissues. Integration of the microRNA screen and expression data revealed miR-9 as the top microRNA, having both functional and clinical significance. MiR-9 levels correlated with HCC tumor stage and miR-9 overexpression induced SNU-449 and HepG2 cell growth, invasiveness and their ability to form colonies in soft agar. Bioinformatics and 3′UTR luciferase analyses identified E-cadherin (CDH1) and peroxisome proliferator-activated receptor alpha (PPARA) as direct downstream effectors of miR-9 activity. Inhibition of PPARA suppressed CDH1 mRNA levels, suggesting that miR-9 regulates CDH1 expression directly through binding in its 3′UTR and indirectly through PPARA. On the other hand, miR-9 inhibition of overexpression suppressed HCC tumorigenicity and invasiveness. PPARA and CDH1 mRNA levels were decreased in HCC relative to controls and were inversely correlated with miR-9 levels. Taken together, this study revealed the involvement of the miR-9/PPARA/CDH1 signaling pathway in HCC oncogenesis. The online version of this article (doi:10.1186/s12885-015-1562-9) contains supplementary material, which is

  10. Chemical Genomic Screening of a Saccharomyces cerevisiae Genomewide Mutant Collection Reveals Genes Required for Defense against Four Antimicrobial Peptides Derived from Proteins Found in Human Saliva

    Science.gov (United States)

    Bhatt, Sanjay; Schoenly, Nathan E.; Lee, Anna Y.; Nislow, Corey; Bobek, Libuse A.

    2013-01-01

    To compare the effects of four antimicrobial peptides (MUC7 12-mer, histatin 12-mer, cathelicidin KR20, and a peptide containing lactoferricin amino acids 1 to 11) on the yeast Saccharomyces cerevisiae, we employed a genomewide fitness screen of combined collections of mutants with homozygous deletions of nonessential genes and heterozygous deletions of essential genes. When an arbitrary fitness score cutoffs of 1 (indicating a fitness defect, or hypersensitivity) and −1 (indicating a fitness gain, or resistance) was used, 425 of the 5,902 mutants tested exhibited altered fitness when treated with at least one peptide. Functional analysis of the 425 strains revealed enrichment among the identified deletions in gene groups associated with the Gene Ontology (GO) terms “ribosomal subunit,” “ribosome biogenesis,” “protein glycosylation,” “vacuolar transport,” “Golgi vesicle transport,” “negative regulation of transcription,” and others. Fitness profiles of all four tested peptides were highly similar, particularly among mutant strains exhibiting the greatest fitness defects. The latter group included deletions in several genes involved in induction of the RIM101 signaling pathway, including several components of the ESCRT sorting machinery. The RIM101 signaling regulates response of yeasts to alkaline and neutral pH and high salts, and our data indicate that this pathway also plays a prominent role in regulating protective measures against all four tested peptides. In summary, the results of the chemical genomic screens of S. cerevisiae mutant collection suggest that the four antimicrobial peptides, despite their differences in structure and physical properties, share many interactions with S. cerevisiae cells and consequently a high degree of similarity between their modes of action. PMID:23208710

  11. A new pharmacological agent (AKB-4924) stabilizes hypoxia inducible factor-1 (HIF-1) and increases skin innate defenses against bacterial infection.

    Science.gov (United States)

    Okumura, Cheryl Y M; Hollands, Andrew; Tran, Dan N; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A; Johnson, Randall S; Nizet, Victor

    2012-09-01

    Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 increases HIF-1 levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinetobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections.

  12. The microRNA miR-29 controls innate and adaptive immune responses to intracellular bacterial infection by targeting interferon-γ.

    Science.gov (United States)

    Ma, Feng; Xu, Sheng; Liu, Xingguang; Zhang, Qian; Xu, Xiongfei; Liu, Mofang; Hua, Minmin; Li, Nan; Yao, Hangping; Cao, Xuetao

    2011-07-24

    Interferon-γ (IFN-γ) has a critical role in immune responses to intracellular bacterial infection. MicroRNAs (miRNAs) are important in the regulation of innate and adaptive immunity. However, whether miRNAs can directly target IFN-γ and regulate IFN-γ production post-transcriptionally remains unknown. Here we show that infection of mice with Listeria monocytogenes or Mycobacterium bovis bacillus Calmette-Guérin (BCG) downregulated miR-29 expression in IFN-γ-producing natural killer cells, CD4(+) T cells and CD8(+) T cells. Moreover, miR-29 suppressed IFN-γ production by directly targeting IFN-γ mRNA. We developed mice with transgenic expression of a 'sponge' target to compete with endogenous miR-29 targets (GS29 mice). We found higher serum concentrations of IFN-γ and lower L. monocytogenes burdens in L. monocytogenes-infected GS29 mice than in their littermates. GS29 mice had enhanced T helper type 1 (T(H)1) responses and greater resistance to infection with BCG or Mycobacterium tuberculosis. Therefore, miR-29 suppresses immune responses to intracellular pathogens by targeting IFN-γ.

  13. Skin bacterial flora as a potential risk factor predisposing to late bacterial infection after cross-linked hyaluronic acid gel augmentation.

    Science.gov (United States)

    Netsvyetayeva, Irina; Marusza, Wojciech; Olszanski, Romuald; Szyller, Kamila; Krolak-Ulinska, Aneta; Swoboda-Kopec, Ewa; Sierdzinski, Janusz; Szymonski, Zachary; Mlynarczyk, Grazyna

    2018-01-01

    Cross-linked hyaluronic acid (HA) gel is widely used in esthetic medicine. Late bacterial infection (LBI) is a rare, but severe complication after HA augmentation. The aim of this study was to determine whether patients who underwent the HA injection procedure and developed LBI had qualitatively different bacterial flora on the skin compared to patients who underwent the procedure without any complications. The study group comprised 10 previously healthy women with recently diagnosed, untreated LBI after HA augmentation. The control group comprised 17 healthy women who had a similar amount of HA injected with no complications. To assess the difference between the two groups, their skin flora was cultured from nasal swabs, both before and after antibiotic treatment in the study group. A significant increase in the incidence of Staphylococcus epidermidis was detected in the control group ( P =0.000) compared to the study group. The study group showed a significantly higher incidence of Staphylococcus aureus ( P =0.005), Klebsiella pneumoniae ( P =0.006), Klebsiella oxytoca ( P =0.048), and Staphylococcus haemolyticus ( P =0.048) compared to the control group. The bacterial flora on the skin differed in patients with LBI from the control group. The control group's bacterial skin flora was dominated by S. epidermidis . Patients with LBI had a bacterial skin flora dominated by potentially pathogenic bacteria.

  14. The Alkaloid Compound Harmane Increases the Lifespan of Caenorhabditis elegans during Bacterial Infection, by Modulating the Nematode’s Innate Immune Response

    Science.gov (United States)

    Marinus, Martin G.; Xu, Tao; Struve, Carsten; Krogfelt, Karen A.; Løbner-Olesen, Anders

    2013-01-01

    The nematode Caenorhabditis elegans has in recent years been proven to be a powerful in vivo model for testing antimicrobial compounds. We report here that the alkaloid compound Harmane (2-methyl-β-carboline) increases the lifespan of nematodes infected with a human pathogen, the Shiga toxin-producing Escherichia coli O157:H7 strain EDL933 and several other bacterial pathogens. This was shown to be unrelated to the weak antibiotic effect of Harmane. Using GFP-expressing E. coli EDL933, we showed that Harmane does not lower the colonization burden in the nematodes. We also found that the expression of the putative immune effector gene F35E12.5 was up-regulated in response to Harmane treatment. This indicates that Harmane stimulates the innate immune response of the nematode; thereby increasing its lifespan during bacterial infection. Expression of F35E12.5 is predominantly regulated through the p38 MAPK pathway; however, intriguingly the lifespan extension resulting from Harmane was higher in p38 MAPK-deficient nematodes. This indicates that Harmane has a complex effect on the innate immune system of C. elegans. Harmane could therefore be a useful tool in the further research into C. elegans immunity. Since the innate immunity of C. elegans has a high degree of evolutionary conservation, drugs such as Harmane could also be possible alternatives to classic antibiotics. The C. elegans model could prove to be useful for selection and development of such drugs. PMID:23544153

  15. Complete genome-wide screening and subtractive genomic approach revealed new virulence factors, potential drug targets against bio-war pathogen Brucella melitensis 16M

    Directory of Open Access Journals (Sweden)

    Pradeepkiran JA

    2015-03-01

    Full Text Available Jangampalli Adi Pradeepkiran,1* Sri Bhashyam Sainath,2,3* Konidala Kranthi Kumar,1 Matcha Bhaskar1 1Division of Animal Biotechnology, Department of Zoology, Sri Venkateswara University, Tirupati, India; 2CIMAR/CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas, Porto, Portugal, 3Department of Biotechnology, Vikrama Simhapuri University, Nellore, Andhra Pradesh, India *These authors contributed equally to this work Abstract: Brucella melitensis 16M is a Gram-negative coccobacillus that infects both animals and humans. It causes a disease known as brucellosis, which is characterized by acute febrile illness in humans and causes abortions in livestock. To prevent and control brucellosis, identification of putative drug targets is crucial. The present study aimed to identify drug targets in B. melitensis 16M by using a subtractive genomic approach. We used available database repositories (Database of Essential Genes, Kyoto Encyclopedia of Genes and Genomes Automatic Annotation Server, and Kyoto Encyclopedia of Genes and Genomes to identify putative genes that are nonhomologous to humans and essential for pathogen B. melitensis 16M. The results revealed that among 3 Mb genome size of pathogen, 53 putative characterized and 13 uncharacterized hypothetical genes were identified; further, from Basic Local Alignment Search Tool protein analysis, one hypothetical protein showed a close resemblance (50% to Silicibacter pomeroyi DUF1285 family protein (2RE3. A further homology model of the target was constructed using MODELLER 9.12 and optimized through variable target function method by molecular dynamics optimization with simulating annealing. The stereochemical quality of the restrained model was evaluated by PROCHECK, VERIFY-3D, ERRAT, and WHATIF servers. Furthermore, structure-based virtual screening was carried out against the predicted active site of the respective protein using the

  16. Disentangling the influence of parasite genotype, host genotype and maternal environment on different stages of bacterial infection in Daphnia magna.

    Science.gov (United States)

    Hall, Matthew D; Ebert, Dieter

    2012-08-22

    Individuals naturally vary in the severity of infectious disease when exposed to a parasite. Dissecting this variation into genetic and environmental components can reveal whether or not this variation depends on the host genotype, parasite genotype or a range of environmental conditions. Complicating this task, however, is that the symptoms of disease result from the combined effect of a series of events, from the initial encounter between a host and parasite, through to the activation of the host immune system and the exploitation of host resources. Here, we use the crustacean Daphnia magna and its parasite Pasteuria ramosa to show how disentangling genetic and environmental factors at different stages of infection improves our understanding of the processes shaping infectious disease. Using compatible host-parasite combinations, we experimentally exclude variation in the ability of a parasite to penetrate the host, from measures of parasite clearance, the reduction in host fecundity and the proliferation of the parasite. We show how parasite resistance consists of two components that vary in environmental sensitivity, how the maternal environment influences all measured aspects of the within-host infection process and how host-parasite interactions following the penetration of the parasite into the host have a distinct temporal component.

  17. JcTI-I: a novel trypsin inhibitor from Jatropha curcas seed cake with potential for bacterial infection treatment.

    Science.gov (United States)

    Costa, Helen P S; Oliveira, Jose T A; Sousa, Daniele O B; Morais, Janne K S; Moreno, Frederico B; Monteiro-Moreira, Ana Cristina O; Viegas, Ricardo A; Vasconcelos, Ilka M

    2014-01-01

    Jatropha curcas seed cake is a low-value by-product resulting from biodiesel production. The seed cake is highly toxic, but it has great potential for biotechnology applications as it is a repository of biomolecules that could be important in agriculture, medicine, and industry. To explore this potential, a novel trypsin inhibitor called JcTI-I was purified by fractionation of the crude extract with trichloroacetic acid (2.5%, v/v) followed by affinity chromatography (Trypsin-Sepharose 4B) and molecular exclusion (Sephacryl S-200). Non-reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration showed that JcTI-I has approximately 20.0~kDa. Mass spectrometry analysis revealed that the intact molecular mass of JcTI-I is 10.252~kDa. Moreover, JcTI-I is a glycoprotein with 6.4% (m/m) carbohydrates, pI of 6.6, N-terminal sequence similarity around 60% to plant albumins and high stability to heat, pH, and salinity. JcTI-I presented antibacterial activity against the human pathogenic bacteria Salmonella enterica subspecies enterica serovar choleraesuis and Staphylococcus aureus, with minimum inhibitory concentration less than 5~μg/mL. Furthermore, JcTI-I did have inhibitory activity against the serine proteases from the tested bacteria. Otherwise, no hemolytic activity of human erythrocytes and signs of acute toxicity to mice were observed for JcTI-I. The results demonstrate the benefits of J. curcas seed cake as a source of trypsin inhibitor with potential for biotechnological application as a new antimicrobial agent against human pathogenic bacteria.

  18. JcTI-I, a novel trypsin inhibitor from Jatropha curcas seed cake with potential for bacterial infection treatment

    Directory of Open Access Journals (Sweden)

    Helen Paula S Costa

    2014-01-01

    Full Text Available Jatropha curcas seed cake is a low-value by-product resulting from biodiesel production. The seed cake is highly toxic, but it has great potential for biotechnology applications as it is a repository of biomolecules that could be important in agriculture, medicine and industry. To explore this potential, a novel trypsin inhibitor called JcTI-I was purified by fractionation of the crude extract with trichloroacetic acid (2.5%, v/v followed by affinity chromatography (Trypsin-Sepharose 4B and molecular exclusion (Sephacryl S-200. Non-reducing SDS-PAGE and gel filtration showed that JcTI-I has approximately 20.0 kDa. Mass spectrometry analysis revealed that the intact molecular mass of JcTI-I is 10.252 kDa. Moreover, JcTI-I is a glycoprotein with 6.4% (m/m carbohydrates, pI of 6.6, N-terminal sequence similarity around 60% to plant albumins and high stability to heat, pH and salinity. JcTI-I presented antibacterial activity against the human pathogenic bacteria Salmonella enterica subspecies enterica serovar choleraesuis and Staphylococcus aureus, with minimum inhibitory concentration (MIC less than 5 µg/mL. Furthermore, JcTI-I did have inhibitory activity against the serine proteases from the tested bacteria. Otherwise, no hemolytic activity of human erythrocytes and signs of acute toxicity to mice were observed for JcTI-I. The results demonstrate the benefits of J. curcas seed cake as a source of trypsin inhibitor with potential for biotechnological application as a new antimicrobial agent against human pathogenic bacteria.

  19. A trans-Amazonian screening of mtDNA reveals deep intraspecific divergence in forest birds and suggests a vast underestimation of species diversity.

    Directory of Open Access Journals (Sweden)

    Borja Milá

    Full Text Available The Amazonian avifauna remains severely understudied relative to that of the temperate zone, and its species richness is thought to be underestimated by current taxonomy. Recent molecular systematic studies using mtDNA sequence reveal that traditionally accepted species-level taxa often conceal genetically divergent subspecific lineages found to represent new species upon close taxonomic scrutiny, suggesting that intraspecific mtDNA variation could be useful in species discovery. Surveys of mtDNA variation in Holarctic species have revealed patterns of variation that are largely congruent with species boundaries. However, little information exists on intraspecific divergence in most Amazonian species. Here we screen intraspecific mtDNA genetic variation in 41 Amazonian forest understory species belonging to 36 genera and 17 families in 6 orders, using 758 individual samples from Ecuador and French Guiana. For 13 of these species, we also analyzed trans-Andean populations from the Ecuadorian Chocó. A consistent pattern of deep intraspecific divergence among trans-Amazonian haplogroups was found for 33 of the 41 taxa, and genetic differentiation and genetic diversity among them was highly variable, suggesting a complex range of evolutionary histories. Mean sequence divergence within families was the same as that found in North American birds (13%, yet mean intraspecific divergence in Neotropical species was an order of magnitude larger (2.13% vs. 0.23%, with mean distance between intraspecific lineages reaching 3.56%. We found no clear relationship between genetic distances and differentiation in plumage color. Our results identify numerous genetically and phenotypically divergent lineages which may result in new species-level designations upon closer taxonomic scrutiny and thorough sampling, although lineages in the tropical region could be older than those in the temperate zone without necessarily representing separate species. In

  20. Development of aptamers for use as radiopharmaceuticals in the bacterial infection identification; Desenvolvimento de aptameros especificos para aplicacao como radiofarmacos na identificacao de bacterias

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ieda Mendes

    2013-08-01

    The difficulty in early detection of specific foci caused by bacteria in the bacterial infection has raised the need to search for new techniques for this purpose, since these foci require prolonged treatment with antibiotics and in some cases even drainage or, if applicable, removal of prostheses or grafts. Detection of bacterial infections by scintigraphy had the advantage that a whole body image could be obtained, since specific tracers were available. This study aims to obtain aptamers specific for bacteria identification for future use as radiopharmaceutical. The SELEX (Systematic Evolution of Ligands by Exponential Enrichment) methodology can generate oligonucleotides (aptamers) that are able to bind with high affinity and specificity to a specific target, from small molecules to complex proteins, by using rounds of enrichment and amplification. Aptamers can be labeled with different radionucleotides such as {sup 99}mTc, {sup 18}F and {sup 32}P. In this study, aptamers anti-peptidoglycan, the main component of the bacterial outer cell wall, were obtained through SELEX. Whole cells of Staphylococcus aureus were also used to perform the SELEX to cells (cell-SELEX). The selection of aptamers was performed by two different procedures (A and B). The A process has been accomplished by 15 SELEX rounds in which the separation of the oligonucleotides bound to the peptidoglycan of unbound ones was performed by filtration. In the B process 15 SELEX rounds were performed using the centrifugation for this separation, followed by 5 rounds cell-SELEX. The SELEX started with a pool of ssDNA (single stranded DNA). For A process, initially a library of ssDNA was incubated with peptidoglycan and the amplification of oligonucleotides that were able to bind to peptidoglycan was performed by PCR (Polymerase Chain Reation). The amplified oligonucleotides were again incubated with peptidoglycan, amplified and purified. At the end of 15 selection rounds the selected oligonucleotides

  1. Impact of a clinical decision model for febrile children at risk for serious bacterial infections at the emergency department: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Evelien de Vos-Kerkhof

    Full Text Available To assess the impact of a clinical decision model for febrile children at risk for serious bacterial infections (SBI attending the emergency department (ED.Randomized controlled trial with 439 febrile children, aged 1 month-16 years, attending the pediatric ED of a Dutch university hospital during 2010-2012. Febrile children were randomly assigned to the intervention (clinical decision model; n = 219 or the control group (usual care; n = 220. The clinical decision model included clinical symptoms, vital signs, and C-reactive protein and provided high/low-risks for "pneumonia" and "other SBI". Nurses were guided by the intervention to initiate additional tests for high-risk children. The clinical decision model was evaluated by 1 area-under-the-receiver-operating-characteristic-curve (AUC to indicate discriminative ability and 2 feasibility, to measure nurses' compliance to model recommendations. Primary patient outcome was defined as correct SBI diagnoses. Secondary process outcomes were defined as length of stay; diagnostic tests; antibiotic treatment; hospital admission; revisits and medical costs.The decision model had good discriminative ability for both pneumonia (n = 33; AUC 0.83 (95% CI 0.75-0.90 and other SBI (n = 22; AUC 0.81 (95% CI 0.72-0.90. Compliance to model recommendations was high (86%. No differences in correct SBI determination were observed. Application of the clinical decision model resulted in less full-blood-counts (14% vs. 22%, p-value < 0.05 and more urine-dipstick testing (71% vs. 61%, p-value < 0.05.In contrast to our expectations no substantial impact on patient outcome was perceived. The clinical decision model preserved, however, good discriminatory ability to detect SBI, achieved good compliance among nurses and resulted in a more standardized diagnostic approach towards febrile children, with less full blood-counts and more rightfully urine-dipstick testing.Nederlands Trial Register NTR2381.

  2. Diagnostic performance of matrix-assisted laser desorption ionisation time-of-flight mass spectrometry in blood bacterial infections: a systematic review and meta-analysis.

    Science.gov (United States)

    Scott, Jamie S; Sterling, Sarah A; To, Harrison; Seals, Samantha R; Jones, Alan E

    2016-07-01

    Matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) has shown promise in decreasing time to identification of causative organisms compared to traditional methods; however, the utility of MALDI-TOF MS in a heterogeneous clinical setting is uncertain. To perform a systematic review on the operational performance of the Bruker MALDI-TOF MS system and evaluate published cut-off values compared to traditional blood cultures. A comprehensive literature search was performed. Studies were included if they performed direct MALDI-TOF MS analysis of blood culture specimens in human patients with suspected bacterial infections using the Bruker Biotyper software. Sensitivities and specificities of the combined studies were estimated using a hierarchical random effects linear model (REML) incorporating cut-off scores of ≥1.7 and ≥2.0. Fifty publications were identified, with 11 studies included after final review. The estimated sensitivity utilising a cut-off of ≥2.0 from the combined studies was 74.6% (95% CI = 67.9-89.3%), with an estimated specificity of 88.0% (95% CI = 74.8-94.7%). When assessing a cut-off of ≥1.7, the combined sensitivity increases to 92.8% (95% CI = 87.4-96.0%), but the estimated specificity decreased to 81.2% (95% CI = 61.9-96.6%). In this analysis, MALDI-TOF MS showed acceptable sensitivity and specificity in bacterial speciation with the current recommended cut-off point compared to blood cultures; however, lowering the cut-off point from ≥2.0 to ≥1.7 would increase the sensitivity of the test without significant detrimental effect on the specificity, which could improve clinician confidence in their results.

  3. Oral associated bacterial infection in horses: studies on the normal anaerobic flora from the pharyngeal tonsillar surface and its association with lower respiratory tract and paraoral infections.

    Science.gov (United States)

    Bailey, G D; Love, D N

    1991-02-15

    Two hundred and seventy bacterial isolates were obtained from the pharyngeal tonsillar surface of 12 normal horses and 98 obligatory anaerobic bacteria were characterised. Of these, 57 isolates belonging to 7 genera (Peptostreptococcus (1); Eubacterium (9); Clostridium (6); Veillonella (6); Megasphera (1); Bacteroides (28); Fusobacterium (6)) were identified, and 16 of these were identified to species level (P. anaerobius (1); E. fossor (9); C. villosum (1); B. fragilis (1); B. tectum (2); B. heparinolyticus (2)). Three hundred and twenty isolates were obtained from 23 samples from horses with lower respiratory tract (LRT) or paraoral (PO) bacterial infections. Of the 143 bacteria selected for detailed characterisation, obligate anaerobes accounted for 100 isolates, facultative anaerobes for 42 isolates and obligate aerobes for one isolate. Phenotypic characterisation separated 99 of the isolates into 14 genera. Among the obligately anaerobic species, Gram-positive cocci including P. anaerobius comprised 25% of isolates, E. fossor 11% and other Gram-positive rods (excluding Clostridium sp.) 18% of isolates. The Gram-negative rods comprised B. fragilis 5%, B. heparinolyticus 5%, asaccharolytic pigmented Bacteroides 3% and other Bacteroides 13%, while a so-far unnamed species of Fusobacterium (7%), and Gram-negative corroding rods (3%) were isolated. Among the facultatively anaerobic isolates, S. equi subsp. zooepidemicus accounted for 31% of isolates, followed by Pasteurella spp. 19%, Escherichia coli 17%, Actinomyces spp. 9%, Streptococcus spp. 9%. Incidental facultative isolates were Enterococcus spp. 2%, Enterobacter cloaceae 2%, Actinobacillus spp. 2% and Gram-negative corroding rods 5%. On the basis of the similarities (as determined by DNA hybridization data and/or phenotypic characteristics) of some of the bacterial species (e.g. E. fossor and B. heparinolyticus) isolated from both the normal pharyngeal tonsillar surfaces and LRT and PO diseases of horses, it

  4. A Genome-Wide Screen for Interactions Reveals a New Locus on 4p15 Modifying the Effect of Waist-to-Hip Ratio on Total Cholesterol

    NARCIS (Netherlands)

    Surakka, Ida; Isaacs, Aaron; Karssen, Lennart C.; Laurila, Pirkka-Pekka P.; Middelberg, Rita P. S.; Tikkanen, Emmi; Ried, Janina S.; Lamina, Claudia; Mangino, Massimo; Igl, Wilmar; Hottenga, Jouke-Jan; Lagou, Vasiliki; van der Harst, Pim; Mateo Leach, Irene; Esko, Tonu; Kutalik, Zoltan; Wainwright, Nicholas W.; Struchalin, Maksim V.; Sarin, Antti-Pekka; Kangas, Antti J.; Viikari, Jorma S.; Perola, Markus; Rantanen, Taina; Petersen, Ann-Kristin; Soininen, Pasi; Johansson, Asa; Soranzo, Nicole; Heath, Andrew C.; Papamarkou, Theodore; Prokopenko, Inga; Toenjes, Anke; Kronenberg, Florian; Doering, Angela; Rivadeneira, Fernando; Montgomery, Grant W.; Whitfield, John B.; Kahonen, Mika; Lehtimaki, Terho; Freimer, Nelson B.; Willemsen, Gonneke; de Geus, Eco J. C.; Palotie, Aarno; Sandhu, Manj S.; Waterworth, Dawn M.; Metspalu, Andres; Stumvoll, Michael; Uitterlinden, Andre G.; Navis, Gerjan; Wijmenga, Cisca; Wolffenbuttel, Bruce H. R.

    2011-01-01

    Recent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain similar to 25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for

  5. A Genome-Wide Screen for Interactions Reveals a New Locus on 4p15 Modifying the Effect of Waist-to-Hip Ratio on Total Cholesterol

    NARCIS (Netherlands)

    Surakka, I.; Isaacs, A.; Karssen, L.C.; Laurila, P.P.P.; Middelberg, R.P.S.; Tikkanen, E.; Ried, J.S.; Lamina, C.; Mangino, M.; Igl, W.; Hottenga, J.J.; Lagou, V.; van der Harst, P.; Mateo Leach, I.; Esko, T.; Kutalik, Z.; Wainwright, N.W.; Struchalin, M.V.; Sarin, A.P.; Kangas, A.J.; Viikari, J.S.; Perola, M.; Rantanen, T.; Petersen, A.K.; Soininen, P.; Johansson, Å.; Soranzo, N.; Heath, A.C.; Papamarkou, T.; Prokopenko, I.; Tönjes, A.; Kronenberg, F.; Döring, A.; Rivadeneira, F.; Montgomery, GW; Whitfield, J.B.; Kähönen, M.; Lehtimäki, T.; Freimer, N.B.; Willemsen, G.; de Geus, E.J.C.; Palotie, A.; Sandhu, M.S.; Waterworth, D.; Metspalu, A.; Stumvoll, M.; Uitterlinden, A.G.; Navis, G.; Wijmenga, C.; Wolffenbuttel, B.H.R.; Taskinen, M.R.; Ala-Korpela, M.; Kaprio, J.; Kyvik, K.O.; Boomsma, D.I.; Pedersen, N.L.; Gyllensten, U.; Wilson, J.F.; Rudan, I.; Campbell, H.; Pramstaller, P.P.; Spector, T.D.; Witteman, J.C.M.; Eriksson, J.G.; Salomaa, V.; Oostra, B.A.; Raitakari, O.T.; Wichmann, H.E.; Gieger, C.; Järvelin, M.J.; Martin, N.G.; Hofman, A.; McCarthy, M.I.; Peltonen, L.; van Duijn, C.M.; Aulchenko, Y.S.; Ripatti, S.

    2011-01-01

    Recent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain ~25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for variants

  6. A genome-wide screen for interactions reveals a new locus on 4p15 modifying the effect of waist-to-hip ratio on total cholesterol

    NARCIS (Netherlands)

    I. Surakka (Ida); A.J. Isaacs (Aaron); L.C. Karssen (Lennart); P.-P.P. Laurila; R.P.S. Middelberg (Rita); E. Tikkanen (Emmi); J.S. Ried (Janina); C. Lamina (Claudia); M. Mangino (Massimo); W. Igl (Wilmar); J.J. Hottenga (Jouke Jan); V. Lagou (Vasiliki); P. van der Harst (Pim); I.M. Leach (Irene Mateo); T. Esko (Tõnu); Z. Kutalik (Zoltán); N.W. Wainwright (Nicholas); M.V. Struchalin (Maksim); A.-P. Sarin; A.J. Kangas (Antti); J. Viikari (Jorma); M. Perola (Markus); T. Rantanen (Taina); A.K. Petersen; P. Soininen (Pasi); A. Johansson (Åsa); N. Soranzo (Nicole); A.C. Heath (Andrew); T. Papamarkou (Theodore); I. Prokopenko (Inga); A. Tönjes (Anke); F. Kronenberg (Florian); A. Döring (Angela); F. Rivadeneira Ramirez (Fernando); G.W. Montgomery (Grant); J.B. Whitfield (John); M. Kähönen (Mika); T. Lehtimäki (Terho); N.B. Freimer (Nelson); G.A.H.M. Willemsen (Gonneke); E.J.C. de Geus (Eco); A. Palotie (Aarno); M.S. Sandhu (Manj); D. Waterworth (Dawn); A. Metspalu (Andres); M. Stumvoll (Michael); A.G. Uitterlinden (André); A. Jula (Antti); G. Navis (Gerjan); C. Wijmenga (Cisca); B.H.R. Wolffenbuttel (Bruce); M.-R. Taskinen; M. Ala-Korpela (Mika); J. Kaprio (Jaakko); K.O. Kyvik (Kirsten Ohm); D.I. Boomsma (Dorret); N.L. Pedersen (Nancy); U. Gyllensten (Ulf); J.F. Wilson (James); I. Rudan (Igor); H. Campbell (Harry); P.P. Pramstaller (Peter Paul); T.D. Spector (Timothy); J.C.M. Witteman (Jacqueline); J.G. Eriksson (Johan); V. Salomaa (Veikko); B.A. Oostra (Ben); O. Raitakari (Olli); H.E. Wichmann (Heinz Erich); C. Gieger (Christian); M.R. Järvelin; N.G. Martin (Nicholas); A. Hofman (Albert); M.I. McCarthy (Mark); Y.S. Aulchenko (Yurii); L. Peltonen (Leena Johanna); P. Tikka-Kleemola (Päivi); S. Ripatti (Samuli)

    2011-01-01

    textabstractRecent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain ~25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for

  7. Sequence-based Screening for Rare Enzymes: New Insights into the World of AMDases Reveal a Conserved Motif and 58 Novel Enzymes Clustering in Eight Distinct Families.

    Directory of Open Access Journals (Sweden)

    Janine Maimanakos

    2016-08-01

    Full Text Available Arylmalonate-Decarboxylases (AMDases, EC 4.1.1.76 are very rare and mostly underexplored enzymes. Currently only four known and biochemically characterized representatives exist. However, their ability to decarboxylate α-disubstituted malonic acid derivatives to optically pure products without cofactors makes them attractive and promising candidates for the use as biocatalysts in industrial processes. Until now, AMDases could not be separated from other members of the aspartate/glutamate racemase superfamily based on their gene sequences. Within this work, a search algorithm was developed that enables a reliable prediction of AMDase activity for potential candidates. Based on specific sequence patterns and screening methods 58 novel AMDase candidate genes could be identified in this work. Thereby, AMDases with the conserved sequence pattern of Bordetella bronchiseptica’s prototype appeared to be limited to the classes of Alpha-, Beta- and Gammaproteobacteria. Amino acid homologies and comparison of gene surrounding sequences enabled the classification of eight enzyme clusters. Particularly striking is the accumulation of genes coding for different transporters of the TTT family, TRAP transporters and ABC transporters as well as genes coding for mandelate racemases/muconate lactonizing enzymes that might be involved in substrate uptake or degradation of AMDase products. Further, three novel AMDases were characterized which showed a high enantiomeric excess (>99% of the (R-enantiomer of flurbiprofen. These are the recombinant AmdA and AmdV from Variovorax sp. strains HH01 and HH02, originated from soil, and AmdP from Polymorphum gilvum found by a data base search. Altogether our findings give new insights into the class of AMDases and reveal many previously unknown enzyme candidates with high potential for bioindustrial processes.

  8. Clustering patterns of LOD scores for asthma-related phenotypes revealed by a genome-wide screen in 295 French EGEA families.

    Science.gov (United States)

    Bouzigon, Emmanuelle; Dizier, Marie-Hélène; Krähenbühl, Christine; Lemainque, Arnaud; Annesi-Maesano, Isabella; Betard, Christine; Bousquet, Jean; Charpin, Denis; Gormand, Frédéric; Guilloud-Bataille, Michel; Just, Jocelyne; Le Moual, Nicole; Maccario, Jean; Matran, Régis; Neukirch, Françoise; Oryszczyn, Marie-Pierre; Paty, Evelyne; Pin, Isabelle; Rosenberg-Bourgin, Myriam; Vervloet, Daniel; Kauffmann, Francine; Lathrop, Mark; Demenais, Florence

    2004-12-15

    A genome-wide scan for asthma phenotypes was conducted in the whole sample of 295 EGEA families selected through at least one asthmatic subject. In addition to asthma, seven phenotypes involved in the main asthma physiopathological pathways were considered: SPT (positive skin prick test response to at least one of 11 allergens), SPTQ score being the number of positive skin test responses to 11 allergens, Phadiatop (positive specific IgE response to a mixture of allergens), total IgE levels, eosinophils, bronchial responsiveness (BR) to methacholine challenge and %predicted FEV(1). Four regions showed evidence for linkage (Pscreens, 6q14 appears to be a new region potentially linked to %FEV(1). To determine which of these various asthma phenotypes are more likely to share common genetic determinants, a principal component analysis was applied to the genome-wide LOD scores. This analysis revealed clustering of LODs for asthma, SPT and Phadiatop on one axis and clustering of LODs for %FEV(1), BR and SPTQ on the other, while LODs for IgE and eosinophils appeared to be independent from all other LODs. These results provide new insights into the potential sharing of genetic determinants by asthma-related phenotypes.

  9. Distinct Biological Potential of Streptococcus gordonii and Streptococcus sanguinis Revealed by Comparative Genome Analysis

    OpenAIRE

    Zheng, Wenning; Tan, Mui Fern; Old, Lesley A.; Paterson, Ian C.; Jakubovics, Nicholas S.; Choo, Siew Woh

    2017-01-01

    Streptococcus gordonii and Streptococcus sanguinis are pioneer colonizers of dental plaque and important agents of bacterial infective endocarditis (IE). To gain a greater understanding of these two closely related species, we performed comparative analyses on 14 new S. gordonii and 5 S. sanguinis strains using various bioinformatics approaches. We revealed S. gordonii and S. sanguinis harbor open pan-genomes and share generally high sequence homology and number of core genes including virule...

  10. Statistical metamodeling for revealing synergistic antimicrobial interactions.

    Directory of Open Access Journals (Sweden)

    Hsiang Chia Chen

    2010-11-01

    Full Text Available Many bacterial pathogens are becoming drug resistant faster than we can develop new antimicrobials. To address this threat in public health, a metamodel antimicrobial cocktail optimization (MACO scheme is demonstrated for rapid screening of potent antibiotic cocktails using uropathogenic clinical isolates as model systems. With the MACO scheme, only 18 parallel trials were required to determine a potent antimicrobial cocktail out of hundreds of possible combinations. In particular, trimethoprim and gentamicin were identified to work synergistically for inhibiting the bacterial growth. Sensitivity analysis indicated gentamicin functions as a synergist for trimethoprim, and reduces its minimum inhibitory concentration for 40-fold. Validation study also confirmed that the trimethoprim-gentamicin synergistic cocktail effectively inhibited the growths of multiple strains of uropathogenic clinical isolates. With its effectiveness and simplicity, the MACO scheme possesses the potential to serve as a generic platform for identifying synergistic antimicrobial cocktails toward management of bacterial infection in the future.

  11. Differential effects of β-catenin and NF-κB interplay in the regulation of cell proliferation, inflammation and tumorigenesis in response to bacterial infection.

    Directory of Open Access Journals (Sweden)

    Parthasarathy Chandrakesan

    .CAST.11M that exhibited significant crypt hyperplasia despite an attenuated NF-κB signaling. Thus, β-catenin and not necessarily NF-κB regulates crypt hyperplasia in response to bacterial infection.

  12. Development and in vitro characterization of poly(lactide-co-glycolide microspheres loaded with an antibacterial natural drug for the treatment of long-term bacterial infections

    Directory of Open Access Journals (Sweden)

    Reinbold J

    2016-09-01

    -loaded microspheres was determined using transmission electron microscopy. No biofilm formation could be detected, even if the totarol concentration was below the minimal inhibitory concentration. The hemocompatibility investigations on various markers with fresh heparinized blood (1.5 IU/mL showed that totarol and totarol-loaded microspheres have no influence on different blood parameters. The PLGA microspheres characterized by slow release of totarol and great entrapment efficiency represent a novel drug delivery system, which may be highly beneficial for the long-term therapy of bacterial infections. Keywords: totarol, drug delivery system, Staphylococcus aureus, antibacterial, cytotoxicity

  13. A Genome-Wide Screen for Interactions Reveals a New Locus on 4p15 Modifying the Effect of Waist-to-Hip Ratio on Total Cholesterol

    DEFF Research Database (Denmark)

    Surakka, I.; Isaacs, A.; Karssen, L. C.

    2011-01-01

    Recent genome-wide association (GWA) studies described 95 loci controlling serum lipid levels. These common variants explain similar to 25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened......, and rs6448771 on 4p15 demonstrated genome-wide significant interaction with waist-to-hip-ratio (WHR) on total cholesterol (TC) with a combined P-value of 4.79 x 10(-9). There were two potential candidate genes in the region, PCDH7 and CCKAR, with differential expression levels for rs6448771 genotypes...

  14. Genome-wide RNAi screen reveals the E3 SUMO-protein ligase gene SIZ1 as a novel determinant of furfural tolerance in Saccharomyces cerevisiae

    OpenAIRE

    Xiao, Han; Zhao, Huimin

    2014-01-01

    Background Furfural is a major growth inhibitor in lignocellulosic hydrolysates and improving furfural tolerance of microorganisms is critical for rapid and efficient fermentation of lignocellulosic biomass. In this study, we used the RNAi-Assisted Genome Evolution (RAGE) method to select for furfural resistant mutants of Saccharomyces cerevisiae, and identified a new determinant of furfural tolerance. Results By using a genome-wide RNAi (RNA-interference) screen in S. cerevisiae for genes in...

  15. A High-Content Phenotypic Screen Reveals the Disruptive Potency of Quinacrine and 3′,4′-Dichlorobenzamil on the Digestive Vacuole of Plasmodium falciparum

    OpenAIRE

    Lee, Yan Quan; Goh, Amanda S. P.; Ch'ng, Jun Hong; Nosten, François H.; Preiser, Peter Rainer; Pervaiz, Shazib; Yadav, Sanjiv Kumar; Tan, Kevin S. W.

    2014-01-01

    Plasmodium falciparum is the etiological agent of malignant malaria and has been shown to exhibit features resembling programmed cell death. This is triggered upon treatment with low micromolar doses of chloroquine or other lysosomotrophic compounds and is associated with leakage of the digestive vacuole contents. In order to exploit this cell death pathway, we developed a high-content screening method to select compounds that can disrupt the parasite vacuole, as measured by the leakage of in...

  16. Systematic analysis of off-target effects in an RNAi screen reveals microRNAs affecting sensitivity to TRAIL-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Enright Anton J

    2010-03-01

    Full Text Available Abstract Background RNA inhibition by siRNAs is a frequently used approach to identify genes required for specific biological processes. However RNAi screening using siRNAs is hampered by non-specific or off target effects of the siRNAs, making it difficult to separate genuine hits from false positives. It is thought that many of the off-target effects seen in RNAi experiments are due to siRNAs acting as microRNAs (miRNAs, causing a reduction in gene expression of unintended targets via matches to the 6 or 7 nt 'seed' sequence. We have conducted a careful examination of off-target effects during an siRNA screen for novel regulators of the TRAIL apoptosis induction pathway(s. Results We identified 3 hexamers and 3 heptamer seed sequences that appeared multiple times in the top twenty siRNAs in the TRAIL apoptosis screen. Using a novel statistical enrichment approach, we systematically identified a further 17 hexamer and 13 heptamer seed sequences enriched in high scoring siRNAs. The presence of one of these seeds sequences (which could explain 6 of 8 confirmed off-target effects is sufficient to elicit a phenotype. Three of these seed sequences appear in the human miRNAs miR-26a, miR-145 and miR-384. Transfection of mimics of these miRNAs protects several cell types from TRAIL-induced cell death. Conclusions We have demonstrated a role for miR-26a, miR-145 and miR-26a in TRAIL-induced apoptosis. Further these results show that RNAi screening enriches for siRNAs with relevant off-target effects. Some of these effects can be identified by the over-representation of certain seed sequences in high-scoring siRNAs and we demonstrate the usefulness of such systematic analysis of enriched seed sequences.

  17. A forward-genetic screen and dynamic analysis of lambda phage host-dependencies reveals an extensive interaction network and a new anti-viral strategy.

    Directory of Open Access Journals (Sweden)

    Nathaniel D Maynard

    2010-07-01

    Full Text Available Latently infecting viruses are an important class of virus that plays a key role in viral evolution and human health. Here we report a genome-scale forward-genetics screen for host-dependencies of the latently-infecting bacteriophage lambda. This screen identified 57 Escherichia coli (E. coli genes--over half of which have not been previously associated with infection--that when knocked out inhibited lambda phage's ability to replicate. Our results demonstrate a highly integrated network between lambda and its host, in striking contrast to the results from a similar screen using the lytic-only infecting T7 virus. We then measured the growth of E. coli under normal and infected conditions, using wild-type and knockout strains deficient in one of the identified host genes, and found that genes from the same pathway often exhibited similar growth dynamics. This observation, combined with further computational and experimental analysis, led us to identify a previously unannotated gene, yneJ, as a novel regulator of lamB gene expression. A surprising result of this work was the identification of two highly conserved pathways involved in tRNA thiolation-one pathway is required for efficient lambda replication, while the other has anti-viral properties inhibiting lambda replication. Based on our data, it appears that 2-thiouridine modification of tRNAGlu, tRNAGln, and tRNALys is particularly important for the efficient production of infectious lambda phage particles.

  18. Depression Screening

    Science.gov (United States)

    ... Depression Screening Substance Abuse Screening Alcohol Use Screening Depression Screening (PHQ-9) - Instructions The following questions are ... this tool, there is also text-only version . Depression Screening - Manual Instructions The following questions are a ...

  19. A buoyancy-based screen of Drosophila larvae for fat-storage mutants reveals a role for Sir2 in coupling fat storage to nutrient availability.

    Directory of Open Access Journals (Sweden)

    Tânia Reis

    2010-11-01

    Full Text Available Obesity has a strong genetic component, but few of the genes that predispose to obesity are known. Genetic screens in invertebrates have the potential to identify genes and pathways that regulate the levels of stored fat, many of which are likely to be conserved in humans. To facilitate such screens, we have developed a simple buoyancy-based screening method for identifying mutant Drosophila larvae with increased levels of stored fat. Using this approach, we have identified 66 genes that when mutated increase organismal fat levels. Among these was a sirtuin family member, Sir2. Sirtuins regulate the storage and metabolism of carbohydrates and lipids by deacetylating key regulatory proteins. However, since mammalian sirtuins function in many tissues in different ways, it has been difficult to define their role in energy homeostasis accurately under normal feeding conditions. We show that knockdown of Sir2 in the larval fat body results in increased fat levels. Moreover, using genetic mosaics, we demonstrate that Sir2 restricts fat accumulation in individual cells of the fat body in a cell-autonomous manner. Consistent with this function, changes in the expression of metabolic enzymes in Sir2 mutants point to a shift away from catabolism. Surprisingly, although Sir2 is typically upregulated under conditions of starvation, Sir2 mutant larvae survive better than wild type under conditions of amino-acid starvation as long as sugars are provided. Our findings point to a Sir2-mediated pathway that activates a catabolic response to amino-acid starvation irrespective of the sugar content of the diet.

  20. Salicylic and jasmonic acid pathways are necessary for defence against Dickeya solani as revealed by a novel method for Blackleg disease screening of in vitro grown potato.

    Science.gov (United States)

    Burra, D D; Mühlenbock, P; Andreasson, E

    2015-09-01

    Potato is major crop ensuring food security in Europe, and blackleg disease is increasingly causing losses in yield and during storage. Recently, one blackleg pathogen, Dickeya solani has been shown to be spreading in Northern Europe that causes aggressive disease development. Currently, identification of tolerant commercial potato varieties has been unsuccessful; this is confounded by the complicated etiology of the disease and a strong environmental influence on disease development. There is currently a lack of efficient testing systems. Here, we describe a system for quantification of blackleg symptoms on shoots of sterile in vitro potato plants, which saves time and space compared to greenhouse and existing field assays. We found no evidence for differences in infection between the described in vitro-based screening method and existing greenhouse assays. This system facilitates efficient screening of blackleg disease response of potato plants independent of other microorganisms and variable environmental conditions. We therefore used the in vitro screening method to increase understanding of plant mechanisms involved in blackleg disease development by analysing disease response of hormone- related (salicylic and jasmonic acid) transgenic potato plants. We show that both jasmonic (JA) and salicylic (SA) acid pathways regulate tolerance to blackleg disease in potato, a result unlike previous findings in Arabidopsis defence response to necrotrophic bacteria. We confirm this by showing induction of a SA marker, pathogenesis-related protein 1 (StPR1), and a JA marker, lipoxygenase (StLOX), in Dickeya solani infected in vitro potato plants. We also observed that tubers of transgenic potato plants were more susceptible to soft rot compared to wild type, suggesting a role for SA and JA pathways in general tolerance to Dickeya. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. 3-Dimensional culture systems for anti-cancer compound profiling and high-throughput screening reveal increases in EGFR inhibitor-mediated cytotoxicity compared to monolayer culture systems.

    Science.gov (United States)

    Howes, Amy L; Richardson, Robyn D; Finlay, Darren; Vuori, Kristiina

    2014-01-01

    3-dimensional (3D) culture models have the potential to bridge the gap between monolayer cell culture and in vivo studies. To benefit anti-cancer drug discovery from 3D models, new techniques are needed that enable their use in high-throughput (HT) screening amenable formats. We have established miniaturized 3D culture methods robust enough for automated HT screens. We have applied these methods to evaluate the sensitivity of normal and tumorigenic breast epithelial cell lines against a panel of oncology drugs when cultured as monolayers (2D) and spheroids (3D). We have identified two classes of compounds that exhibit preferential cytotoxicity against cancer cells over normal cells when cultured as 3D spheroids: microtubule-targeting agents and epidermal growth factor receptor (EGFR) inhibitors. Further improving upon our 3D model, superior differentiation of EC50 values in the proof-of-concept screens was obtained by co-culturing the breast cancer cells with normal human fibroblasts and endothelial cells. Further, the selective sensitivity of the cancer cells towards chemotherapeutics was observed in 3D co-culture conditions, rather than as 2D co-culture monolayers, highlighting the importance of 3D cultures. Finally, we examined the putative mechanisms that drive the differing potency displayed by EGFR inhibitors. In summary, our studies establish robust 3D culture models of human cells for HT assessment of tumor cell-selective agents. This methodology is anticipated to provide a useful tool for the study of biological differences within 2D and 3D culture conditions in HT format, and an important platform for novel anti-cancer drug discovery.

  2. A screen for F1 hybrid male rescue reveals no major-effect hybrid lethality loci in the Drosophila melanogaster autosomal genome.

    Science.gov (United States)

    Cuykendall, Tawny N; Satyaki, P; Ji, Shuqing; Clay, Derek M; Edelman, Nathaniel B; Kimchy, Alexandra; Li, Ling-Hei; Nuzzo, Erin A; Parekh, Neil; Park, Suna; Barbash, Daniel A

    2014-10-27

    Hybrid sons between Drosophila melanogaster females and D. simulans males die as 3rd instar larvae. Two genes, D. melanogaster Hybrid male rescue (Hmr) on the X chromosome, and D. simulans Lethal hybrid rescue (Lhr) on chromosome II, interact to cause this lethality. Loss-of-function mutations in either gene suppress lethality, but several pieces of evidence suggest that additional factors are required for hybrid lethality. Here we screen the D. melanogaster autosomal genome by using the Bloomington Stock Center Deficiency kit to search for additional regions that can rescue hybrid male lethality. Our screen is designed to identify putative hybrid incompatibility (HI) genes similar to Hmr and Lhr which, when removed, are dominant suppressors of lethality. After screening 89% of the autosomal genome, we found no regions that rescue males to the adult stage. We did, however, identify several regions that rescue up to 13% of males to the pharate adult stage. This weak rescue suggests the presence of multiple minor-effect HI loci, but we were unable to map these loci to high resolution, presumably because weak rescue can be masked by genetic background effects. We attempted to test one candidate, the dosage compensation gene male specific lethal-3 (msl-3), by using RNA interference with short hairpin microRNA constructs targeted specifically against D. simulans msl-3 but failed to achieve knockdown, in part due to off-target effects. We conclude that the D. melanogaster autosomal genome likely does not contain additional major-effect HI loci. We also show that Hmr is insufficient to fully account for the lethality associated with the D. melanogaster X chromosome, suggesting that additional X-linked genes contribute to hybrid lethality. Copyright © 2014 Cuykendall et al.

  3. A genetic screen for modifiers of Drosophila caspase Dcp-1 reveals caspase involvement in autophagy and novel caspase-related genes

    Directory of Open Access Journals (Sweden)

    Ahnn Joohong

    2010-01-01

    Full Text Available Abstract Background Caspases are cysteine proteases with essential functions in the apoptotic pathway; their proteolytic activity toward various substrates is associated with the morphological changes of cells. Recent reports have described non-apoptotic functions of caspases, including autophagy. In this report, we searched for novel modifiers of the phenotype of Dcp-1 gain-of-function (GF animals by screening promoter element- inserted Drosophila melanogaster lines (EP lines. Results We screened ~15,000 EP lines and identified 72 Dcp-1-interacting genes that were classified into 10 groups based on their functions and pathways: 4 apoptosis signaling genes, 10 autophagy genes, 5 insulin/IGF and TOR signaling pathway genes, 6 MAP kinase and JNK signaling pathway genes, 4 ecdysone signaling genes, 6 ubiquitination genes, 11 various developmental signaling genes, 12 transcription factors, 3 translation factors, and 11 other unclassified genes including 5 functionally undefined genes. Among them, insulin/IGF and TOR signaling pathway, MAP kinase and JNK signaling pathway, and ecdysone signaling are known to be involved in autophagy. Together with the identification of autophagy genes, the results of our screen suggest that autophagy counteracts Dcp-1-induced apoptosis. Consistent with this idea, we show that expression of eGFP-Atg5 rescued the eye phenotype caused by Dcp-1 GF. Paradoxically, we found that over-expression of full-length Dcp-1 induced autophagy, as Atg8b-GFP, an indicator of autophagy, was increased in the eye imaginal discs and in the S2 cell line. Taken together, these data suggest that autophagy suppresses Dcp-1-mediated apoptotic cell death, whereas Dcp-1 positively regulates autophagy, possibly through feedback regulation. Conclusions We identified a number of Dcp-1 modifiers that genetically interact with Dcp-1-induced cell death. Our results showing that Dcp-1 and autophagy-related genes influence each other will aid future

  4. PCR screening reveals considerable unexploited biosynthetic potential of ansamycins and a mysterious family of AHBA-containing natural products in actinomycetes.

    Science.gov (United States)

    Wang, H-X; Chen, Y-Y; Ge, L; Fang, T-T; Meng, J; Liu, Z; Fang, X-Y; Ni, S; Lin, C; Wu, Y-Y; Wang, M-L; Shi, N-N; He, H-G; Hong, K; Shen, Y-M

    2013-07-01

    Ansamycins are a family of macrolactams that are synthesized by type I polyketide synthase (PKS) using 3-amino-5-hydroxybenzoic acid (AHBA) as the starter unit. Most members of the family have strong antimicrobial, antifungal, anticancer and/or antiviral activities. We aimed to discover new ansamycins and/or other AHBA-containing natural products from actinobacteria. Through PCR screening of AHBA synthase gene, we identified 26 AHBA synthase gene-positive strains from 206 plant-associated actinomycetes (five positives) and 688 marine-derived actinomycetes (21 positives), representing a positive ratio of 2·4-3·1%. Twenty-five ansamycins, including eight new compounds, were isolated from six AHBA synthase gene-positive strains through TLC-guided fractionations followed by repeated column chromatography. To gain information about those potential ansamycin gene clusters whose products were unknown, seven strains with phylogenetically divergent AHBA synthase genes were subjected to fosmid library construction. Of the seven gene clusters we obtained, three show characteristics for typical ansamycin gene clusters, and other four, from Micromonospora spp., appear to lack the amide synthase gene, which is unusual for ansamycin biosynthesis. The gene composition of these four gene clusters suggests that they are involved in the biosynthesis of a new family of hybrid PK-NRP compounds containing AHBA substructure. PCR screening of AHBA synthase is an efficient approach to discover novel ansamycins and other AHBA-containing natural products. This work demonstrates that the AHBA-based screening method is a useful approach for discovering novel ansamycins and other AHBA-containing natural products from new microbial resources. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

  5. High-Throughput Flow Cytometry Screening Reveals a Role for Junctional Adhesion Molecule A as a Cancer Stem Cell Maintenance Factor

    DEFF Research Database (Denmark)

    Lathia, Justin D; Li, Meizhang; Sinyuk, Maksim

    2014-01-01

    Stem cells reside in niches that regulate the balance between self-renewal and differentiation. The identity of a stem cell is linked with the ability to interact with its niche through adhesion mechanisms. To identify targets that disrupt cancer stem cell (CSC) adhesion, we performed a flow...... brain versus GBM. Targeting JAM-A compromised the self-renewal of CSCs. JAM-A expression negatively correlated to GBM patient prognosis. Our results demonstrate that GBM-targeting strategies can be identified through screening adhesion receptors and JAM-A represents a mechanism for niche-driven CSC...

  6. Comparison of the IKr blockers moxifloxacin, dofetilide and E-4031 in five screening models of pro-arrhythmia reveals lack of specificity of isolated cardiomyocytes

    DEFF Research Database (Denmark)

    Nalos, L; Varkevisser, R; Jonsson, Mkb

    2012-01-01

    Background and purpose Drug discovery and development require testing of new chemical entities for possible adverse effects. For cardiac safety screening, improved assays are urgently needed and isolated adult cardiomyocytes (CM) and human embryonic stem cell-derived cardiomyocytes (hESC-CM) may......-4031 (unsafe compounds). Experimental approach The assays included: 1. The anesthetized remodeled chronic complete AV-block (CAVB) dog, 2. The anesthetized methoxamine sensitized unremodeled rabbit, 3. Multi-cellular hESC-CM clusters, 4. Isolated CM obtained from the CAVB dog and 5. Isolated CM...

  7. High-Throughput Flow Cytometry Screening Reveals a Role for Junctional Adhesion Molecule A as a Cancer Stem Cell Maintenance Factor

    Directory of Open Access Journals (Sweden)

    Justin D. Lathia

    2014-01-01

    Full Text Available Stem cells reside in niches that regulate the balance between self-renewal and differentiation. The identity of a stem cell is linked with the ability to interact with its niche through adhesion mechanisms. To identify targets that disrupt cancer stem cell (CSC adhesion, we performed a flow cytometry screen on patient-derived glioblastoma (GBM cells and identified junctional adhesion molecule A (JAM-A as a CSC adhesion mechanism essential for self-renewal and tumor growth. JAM-A was dispensable for normal neural stem/progenitor cell (NPC function, and JAM-A expression was reduced in normal brain versus GBM. Targeting JAM-A compromised the self-renewal of CSCs. JAM-A expression negatively correlated to GBM patient prognosis. Our results demonstrate that GBM-targeting strategies can be identified through screening adhesion receptors and JAM-A represents a mechanism for niche-driven CSC maintenance.

  8. A high-content phenotypic screen reveals the disruptive potency of quinacrine and 3',4'-dichlorobenzamil on the digestive vacuole of Plasmodium falciparum.

    Science.gov (United States)

    Lee, Yan Quan; Goh, Amanda S P; Ch'ng, Jun Hong; Nosten, François H; Preiser, Peter Rainer; Pervaiz, Shazib; Yadav, Sanjiv Kumar; Tan, Kevin S W

    2014-01-01

    Plasmodium falciparum is the etiological agent of malignant malaria and has been shown to exhibit features resembling programmed cell death. This is triggered upon treatment with low micromolar doses of chloroquine or other lysosomotrophic compounds and is associated with leakage of the digestive vacuole contents. In order to exploit this cell death pathway, we developed a high-content screening method to select compounds that can disrupt the parasite vacuole, as measured by the leakage of intravacuolar Ca(2+). This assay uses the ImageStream 100, an imaging-capable flow cytometer, to assess the distribution of the fluorescent calcium probe Fluo-4. We obtained two hits from a small library of 25 test compounds, quinacrine and 3',4'-dichlorobenzamil. The ability of these compounds to permeabilize the digestive vacuole in laboratory strains and clinical isolates was validated by confocal microscopy. The hits could induce programmed cell death features in both chloroquine-sensitive and -resistant laboratory strains. Quinacrine was effective at inhibiting field isolates in a 48-h reinvasion assay regardless of artemisinin clearance status. We therefore present as proof of concept a phenotypic screening method with the potential to provide mechanistic insights to the activity of antimalarial drugs.

  9. High content image-based screening of a protease inhibitor library reveals compounds broadly active against Rift Valley fever virus and other highly pathogenic RNA viruses.

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    Rajini Mudhasani

    2014-08-01

    Full Text Available High content image-based screening was developed as an approach to test a protease inhibitor small molecule library for antiviral activity against Rift Valley fever virus (RVFV and to determine their mechanism of action. RVFV is the causative agent of severe disease of humans and animals throughout Africa and the Arabian Peninsula. Of the 849 compounds screened, 34 compounds exhibited ≥ 50% inhibition against RVFV. All of the hit compounds could be classified into 4 distinct groups based on their unique chemical backbone. Some of the compounds also showed broad antiviral activity against several highly pathogenic RNA viruses including Ebola, Marburg, Venezuela equine encephalitis, and Lassa viruses. Four hit compounds (C795-0925, D011-2120, F694-1532 and G202-0362, which were most active against RVFV and showed broad-spectrum antiviral activity, were selected for further evaluation for their cytotoxicity, dose response profile, and mode of action using classical virological methods and high-content imaging analysis. Time-of-addition assays in RVFV infections suggested that D011-2120 and G202-0362 targeted virus egress, while C795-0925 and F694-1532 inhibited virus replication. We showed that D011-2120 exhibited its antiviral effects by blocking microtubule polymerization, thereby disrupting the Golgi complex and inhibiting viral trafficking to the plasma membrane during virus egress. While G202-0362 also affected virus egress, it appears to do so by a different mechanism, namely by blocking virus budding from the trans Golgi. F694-1532 inhibited viral replication, but also appeared to inhibit overall cellular gene expression. However, G202-0362 and C795-0925 did not alter any of the morphological features that we examined and thus may prove to be good candidates for antiviral drug development. Overall this work demonstrates that high-content image analysis can be used to screen chemical libraries for new antivirals and to determine their

  10. Screening And Optimizing Antimicrobial Peptides By Using SPOT-Synthesis

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    López-Pérez, Paula M.; Grimsey, Elizabeth; Bourne, Luc; Mikut, Ralf; Hilpert, Kai

    2017-04-01

    Peptide arrays on cellulose are a powerful tool to investigate peptide interactions with a number of different molecules, for examples antibodies, receptors or enzymes. Such peptide arrays can also be used to study interactions with whole cells. In this review, we focus on the interaction of small antimicrobial peptides with bacteria. Antimicrobial peptides (AMPs) can kill multidrug-resistant (MDR) human pathogenic bacteria and therefore could be next generation antibiotics targeting MDR bacteria. We describe the screen and the result of different optimization strategies of peptides cleaved from the membrane. In addition, screening of antibacterial activity of peptides that are tethered to the surface is discussed. Surface-active peptides can be used to protect surfaces from bacterial infections, for example implants.

  11. Dual microRNA Screens Reveal That the Immune-Responsive miR-181 Promotes Henipavirus Entry and Cell-Cell Fusion.

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    Chwan Hong Foo

    2016-10-01

    Full Text Available Hendra and Nipah viruses (family Paramyxoviridae, genus Henipavirus are bat-borne viruses that cause fatal disease in humans and a range of other mammalian species. Gaining a deeper understanding of host pathways exploited by henipaviruses for infection may identify targets for new anti-viral therapies. Here we have performed genome-wide high-throughput agonist and antagonist screens at biosafety level 4 to identify host-encoded microRNAs (miRNAs impacting henipavirus infection in human cells. Members of the miR-181 and miR-17~93 families strongly promoted Hendra virus infection. miR-181 also promoted Nipah virus infection, but did not affect infection by paramyxoviruses from other genera, indicating specificity in the virus-host interaction. Infection promotion was primarily mediated via the ability of miR-181 to significantly enhance henipavirus-induced membrane fusion. Cell signalling receptors of ephrins, namely EphA5 and EphA7, were identified as novel negative regulators of henipavirus fusion. The expression of these receptors, as well as EphB4, were suppressed by miR-181 overexpression, suggesting that simultaneous inhibition of several Ephs by the miRNA contributes to enhanced infection and fusion. Immune-responsive miR-181 levels was also up-regulated in the biofluids of ferrets and horses infected with Hendra virus, suggesting that the host innate immune response may promote henipavirus spread and exacerbate disease severity. This study is the first genome-wide screen of miRNAs influencing infection by a clinically significant mononegavirus and nominates select miRNAs as targets for future anti-viral therapy development.

  12. Possible roles of vacuolar H+-ATPase and mitochondrial function in tolerance to air-drying stress revealed by genome-wide screening of Saccharomyces cerevisiae deletion strains.

    Science.gov (United States)

    Shima, Jun; Ando, Akira; Takagi, Hiroshi

    2008-03-01

    Yeasts used in bread making are exposed to air-drying stress during dried yeast production processes. To clarify the genes required for air-drying tolerance, we performed genome-wide screening using the complete deletion strain collection of diploid Saccharomyces cerevisiae. The screening identified 278 gene deletions responsible for air-drying sensitivity. These genes were classified based on their cellular function and on the localization of their gene products. The results showed that the genes required for air-drying tolerance were frequently involved in mitochondrial functions and in connection with vacuolar H(+)-ATPase, which plays a role in vacuolar acidification. To determine the role of vacuolar acidification in air-drying stress tolerance, we monitored intracellular pH. The results showed that intracellular acidification was induced during air-drying and that this acidification was amplified in a deletion mutant of the VMA2 gene encoding a component of vacuolar H(+)-ATPase, suggesting that vacuolar H(+)-ATPase helps maintain intracellular pH homeostasis, which is affected by air-drying stress. To determine the effects of air-drying stress on mitochondria, we analysed the mitochondrial membrane potential under air-drying stress conditions using MitoTracker. The results showed that mitochondria were extremely sensitive to air-drying stress, suggesting that a mitochondrial function is required for tolerance to air-drying stress. We also analysed the correlation between oxidative-stress sensitivity and air-drying-stress sensitivity. The results suggested that oxidative stress is a critical determinant of sensitivity to air-drying stress, although ROS-scavenging systems are not necessary for air-drying stress tolerance. (c) 2008 John Wiley & Sons, Ltd.

  13. A genome-wide screen for interactions reveals a new locus on 4p15 modifying the effect of waist-to-hip ratio on total cholesterol.

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    Ida Surakka

    2011-10-01

    Full Text Available Recent genome-wide association (GWA studies described 95 loci controlling serum lipid levels. These common variants explain ∼25% of the heritability of the phenotypes. To date, no unbiased screen for gene-environment interactions for circulating lipids has been reported. We screened for variants that modify the relationship between known epidemiological risk factors and circulating lipid levels in a meta-analysis of genome-wide association (GWA data from 18 population-based cohorts with European ancestry (maximum N = 32,225. We collected 8 further cohorts (N = 17,102 for replication, and rs6448771 on 4p15 demonstrated genome-wide significant interaction with waist-to-hip-ratio (WHR on total cholesterol (TC with a combined P-value of 4.79×10(-9. There were two potential candidate genes in the region, PCDH7 and CCKAR, with differential expression levels for rs6448771 genotypes in adipose tissue. The effect of WHR on TC was strongest for individuals carrying two copies of G allele, for whom a one standard deviation (sd difference in WHR corresponds to 0.19 sd difference in TC concentration, while for A allele homozygous the difference was 0.12 sd. Our findings may open up possibilities for targeted intervention strategies for people characterized by specific genomic profiles. However, more refined measures of both body-fat distribution and metabolic measures are needed to understand how their joint dynamics are modified by the newly found locus.

  14. Comparison of independent screens on differentially vulnerable motor neurons reveals alpha-synuclein as a common modifier in motor neuron diseases.

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    Kline, Rachel A; Kaifer, Kevin A; Osman, Erkan Y; Carella, Francesco; Tiberi, Ariana; Ross, Jolill; Pennetta, Giuseppa; Lorson, Christian L; Murray, Lyndsay M

    2017-03-01

    The term "motor neuron disease" encompasses a spectrum of disorders in which motor neurons are the primary pathological target. However, in both patients and animal models of these diseases, not all motor neurons are equally vulnerable, in that while some motor neurons are lost very early in disease, others remain comparatively intact, even at late stages. This creates a valuable system to investigate the factors that regulate motor neuron vulnerability. In this study, we aim to use this experimental paradigm to identify potential transcriptional modifiers. We have compared the transcriptome of motor neurons from healthy wild-type mice, which are differentially vulnerable in the childhood motor neuron disease Spinal Muscular Atrophy (SMA), and have identified 910 transcriptional changes. We have compared this data set with published microarray data sets on other differentially vulnerable motor neurons. These neurons were differentially vulnerable in the adult onset motor neuron disease Amyotrophic Lateral Sclerosis (ALS), but the screen was performed on the equivalent population of neurons from neurologically normal human, rat and mouse. This cross species comparison has generated a refined list of differentially expressed genes, including CELF5, Col5a2, PGEMN1, SNCA, Stmn1 and HOXa5, alongside a further enrichment for synaptic and axonal transcripts. As an in vivo validation, we demonstrate that the manipulation of a significant number of these transcripts can modify the neurodegenerative phenotype observed in a Drosophila line carrying an ALS causing mutation. Finally, we demonstrate that vector-mediated expression of alpha-synuclein (SNCA), a transcript decreased in selectively vulnerable motor neurons in all four screens, can extend life span, increase weight and decrease neuromuscular junction pathology in a mouse model of SMA. In summary, we have combined multiple data sets to identify transcripts, which are strong candidates for being phenotypic modifiers

  15. Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

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    Baril, Martin; Es-Saad, Salwa; Chatel-Chaix, Laurent; Fink, Karin; Pham, Tram; Raymond, Valérie-Ann; Audette, Karine; Guenier, Anne-Sophie; Duchaine, Jean; Servant, Marc; Bilodeau, Marc; Cohen, Eric; Grandvaux, Nathalie; Lamarre, Daniel

    2013-01-01

    To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1) promoter following Sendai virus (SeV) infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1) upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3) inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

  16. Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

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    Martin Baril

    Full Text Available To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1 promoter following Sendai virus (SeV infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I-like receptor (RLR-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1 upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3 inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

  17. Screening of random peptide library of hemagglutinin from pandemic 2009 A(H1N1 influenza virus reveals unexpected antigenically important regions.

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    Wanghui Xu

    Full Text Available The antigenic structure of the membrane protein hemagglutinin (HA from the 2009 A(H1N1 influenza virus was dissected with a high-throughput screening method using complex antisera. The approach involves generating yeast cell libraries displaying a pool of random peptides of controllable lengths on the cell surface, followed by one round of fluorescence-activated cell sorting (FACS against antisera from mouse, goat and human, respectively. The amino acid residue frequency appearing in the antigenic peptides at both the primary sequence and structural level was determined and used to identify "hot spots" or antigenically important regions. Unexpectedly, different antigenic structures were seen for different antisera. Moreover, five antigenic regions were identified, of which all but one are located in the conserved HA stem region that is responsible for membrane fusion. Our findings are corroborated by several recent studies on cross-neutralizing H1 subtype antibodies that recognize the HA stem region. The antigenic peptides identified may provide clues for creating peptide vaccines with better accessibility to memory B cells and better induction of cross-neutralizing antibodies than the whole HA protein. The scheme used in this study enables a direct mapping of the antigenic regions of viral proteins recognized by antisera, and may be useful for dissecting the antigenic structures of other viral proteins.

  18. In Vivo Loss of Function Screening Reveals Carbonic Anhydrase IX as a Key Modulator of Tumor Initiating Potential in Primary Pancreatic Tumors

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    Nabendu Pore

    2015-06-01

    Full Text Available Reprogramming of energy metabolism is one of the emerging hallmarks of cancer. Up-regulation of energy metabolism pathways fuels cell growth and division, a key characteristic of neoplastic disease, and can lead to dependency on specific metabolic pathways. Thus, targeting energy metabolism pathways might offer the opportunity for novel therapeutics. Here, we describe the application of a novel in vivo screening approach for the identification of genes involved in cancer metabolism using a patient-derived pancreatic xenograft model. Lentiviruses expressing short hairpin RNAs (shRNAs targeting 12 different cell surface protein transporters were separately transduced into the primary pancreatic tumor cells. Transduced cells were pooled and implanted into mice. Tumors were harvested at different times, and the frequency of each shRNA was determined as a measure of which ones prevented tumor growth. Several targets including carbonic anhydrase IX (CAIX, monocarboxylate transporter 4, and anionic amino acid transporter light chain, xc- system (xCT were identified in these studies and shown to be required for tumor initiation and growth. Interestingly, CAIX was overexpressed in the tumor initiating cell population. CAIX expression alone correlated with a highly tumorigenic subpopulation of cells. Furthermore, CAIX expression was essential for tumor initiation because shRNA knockdown eliminated the ability of cells to grow in vivo. To the best of our knowledge, this is the first parallel in vivo assessment of multiple novel oncology target genes using a patient-derived pancreatic tumor model.

  19. High-Throughput Genetic Screen Reveals that Early Attachment and Biofilm Formation Are Necessary for Full Pyoverdine Production by Pseudomonas aeruginosa

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    Donghoon Kang

    2017-09-01

    Full Text Available Pseudomonas aeruginosa is a re-emerging, multidrug-resistant, opportunistic pathogen that threatens the lives of immunocompromised patients, patients with cystic fibrosis, and those in critical care units. One of the most important virulence factors in this pathogen is the siderophore pyoverdine. Pyoverdine serves several critical roles during infection. Due to its extremely high affinity for ferric iron, pyoverdine gives the pathogen a significant advantage over the host in their competition for iron. In addition, pyoverdine can regulate the production of multiple bacterial virulence factors and perturb host mitochondrial homeostasis. Inhibition of pyoverdine biosynthesis decreases P. aeruginosa pathogenicity in multiple host models. To better understand the regulation of pyoverdine production, we developed a high-throughput genetic screen that uses the innate fluorescence of pyoverdine to identify genes necessary for its biosynthesis. A substantial number of hits showing severe impairment of pyoverdine production were in genes responsible for early attachment and biofilm formation. In addition to genetic disruption of biofilm, both physical and chemical perturbations also attenuated pyoverdine production. This regulatory relationship between pyoverdine and biofilm is particularly significant in the context of P. aeruginosa multidrug resistance, where the formation of biofilm is a key mechanism preventing access to antimicrobials and the immune system. Furthermore, we demonstrate that the biofilm inhibitor 2-amino-5,6-dimethylbenzimidazole effectively attenuates pyoverdine production and rescues Caenorhabditis elegans from P. aeruginosa-mediated pathogenesis. Our findings suggest that targeting biofilm formation in P. aeruginosa infections may have multiple therapeutic benefits and that employing an unbiased, systems biology-based approach may be useful for understanding the regulation of specific virulence factors and identifying novel anti

  20. Large-scale community echocardiographic screening reveals a major burden of undiagnosed valvular heart disease in older people: the OxVALVE Population Cohort Study†

    Science.gov (United States)

    d'Arcy, Joanna L.; Coffey, Sean; Loudon, Margaret A.; Kennedy, Andrew; Pearson-Stuttard, Jonathan; Birks, Jacqueline; Frangou, Eleni; Farmer, Andrew J.; Mant, David; Wilson, Jo; Myerson, Saul G.; Prendergast, Bernard D.

    2016-01-01

    Background Valvular heart disease (VHD) is expected to become more common as the population ages. However, current estimates of its natural history and prevalence are based on historical studies with potential sources of bias. We conducted a cross-sectional analysis of the clinical and epidemiological characteristics of VHD identified at recruitment of a large cohort of older people. Methods and results We enrolled 2500 individuals aged ≥65 years from a primary care population and screened for undiagnosed VHD using transthoracic echocardiography. Newly identified (predominantly mild) VHD was detected in 51% of participants. The most common abnormalities were aortic sclerosis (34%), mitral regurgitation (22%), and aortic regurgitation (15%). Aortic stenosis was present in 1.3%. The likelihood of undiagnosed VHD was two-fold higher in the two most deprived socioeconomic quintiles than in the most affluent quintile, and three-fold higher in individuals with atrial fibrillation. Clinically significant (moderate or severe) undiagnosed VHD was identified in 6.4%. In addition, 4.9% of the cohort had pre-existing VHD (a total prevalence of 11.3%). Projecting these findings using population data, we estimate that the prevalence of clinically significant VHD will double before 2050. Conclusions Previously undetected VHD affects 1 in 2 of the elderly population and is more common in lower socioeconomic classes. These unique data demonstrate the contemporary clinical and epidemiological characteristics of VHD in a large population-based cohort of older people and confirm the scale of the emerging epidemic of VHD, with widespread implications for clinicians and healthcare resources. PMID:27354049

  1. Large-scale community echocardiographic screening reveals a major burden of undiagnosed valvular heart disease in older people: the OxVALVE Population Cohort Study.

    Science.gov (United States)

    d'Arcy, Joanna L; Coffey, Sean; Loudon, Margaret A; Kennedy, Andrew; Pearson-Stuttard, Jonathan; Birks, Jacqueline; Frangou, Eleni; Farmer, Andrew J; Mant, David; Wilson, Jo; Myerson, Saul G; Prendergast, Bernard D

    2016-12-14

    Valvular heart disease (VHD) is expected to become more common as the population ages. However, current estimates of its natural history and prevalence are based on historical studies with potential sources of bias. We conducted a cross-sectional analysis of the clinical and epidemiological characteristics of VHD identified at recruitment of a large cohort of older people. We enrolled 2500 individuals aged ≥65 years from a primary care population and screened for undiagnosed VHD using transthoracic echocardiography. Newly identified (predominantly mild) VHD was detected in 51% of participants. The most common abnormalities were aortic sclerosis (34%), mitral regurgitation (22%), and aortic regurgitation (15%). Aortic stenosis was present in 1.3%. The likelihood of undiagnosed VHD was two-fold higher in the two most deprived socioeconomic quintiles than in the most affluent quintile, and three-fold higher in individuals with atrial fibrillation. Clinically significant (moderate or severe) undiagnosed VHD was identified in 6.4%. In addition, 4.9% of the cohort had pre-existing VHD (a total prevalence of 11.3%). Projecting these findings using population data, we estimate that the prevalence of clinically significant VHD will double before 2050. Previously undetected VHD affects 1 in 2 of the elderly population and is more common in lower socioeconomic classes. These unique data demonstrate the contemporary clinical and epidemiological characteristics of VHD in a large population-based cohort of older people and confirm the scale of the emerging epidemic of VHD, with widespread implications for clinicians and healthcare resources. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  2. A compact, in vivo screen of all 6-mers reveals drivers of tissue-specific expression and guides synthetic regulatory element design.

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    Smith, Robin P; Riesenfeld, Samantha J; Holloway, Alisha K; Li, Qiang; Murphy, Karl K; Feliciano, Natalie M; Orecchia, Lorenzo; Oksenberg, Nir; Pollard, Katherine S; Ahituv, Nadav

    2013-07-18

    Large-scale annotation efforts have improved our ability to coarsely predict regulatory elements throughout vertebrate genomes. However, it is unclear how complex spatiotemporal patterns of gene expression driven by these elements emerge from the activity of short, transcription factor binding sequences. We describe a comprehensive promoter extension assay in which the regulatory potential of all 6 base-pair (bp) sequences was tested in the context of a minimal promoter. To enable this large-scale screen, we developed algorithms that use a reverse-complement aware decomposition of the de Bruijn graph to design a library of DNA oligomers incorporating every 6-bp sequence exactly once. Our library multiplexes all 4,096 unique 6-mers into 184 double-stranded 15-bp oligomers, which is sufficiently compact for in vivo testing. We injected each multiplexed construct into zebrafish embryos and scored GFP expression in 15 tissues at two developmental time points. Twenty-seven constructs produced consistent expression patterns, with the majority doing so in only one tissue. Functional sequences are enriched near biologically relevant genes, match motifs for developmental transcription factors, and are required for enhancer activity. By concatenating tissue-specific functional sequences, we generated completely synthetic enhancers for the notochord, epidermis, spinal cord, forebrain and otic lateral line, and show that short regulatory sequences do not always function modularly. This work introduces a unique in vivo catalog of short, functional regulatory sequences and demonstrates several important principles of regulatory element organization. Furthermore, we provide resources for designing compact, reverse-complement aware k-mer libraries.

  3. Functional enhancement of AT1R potency in the presence of the TPαR is revealed by a comprehensive 7TM receptor co-expression screen.

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    Jonas Tind Hansen

    Full Text Available BACKGROUND: Functional cross-talk between seven transmembrane (7TM receptors can dramatically alter their pharmacological properties, both in vitro and in vivo. This represents an opportunity for the development of novel therapeutics that potentially target more specific biological effects while causing fewer adverse events. Although several studies convincingly have established the existence of 7TM receptor cross-talk, little is known about the frequencey and biological significance of this phenomenon. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate the extent of synergism in 7TM receptor signaling, we took a comprehensive approach and co-expressed 123 different 7TM receptors together with the angiotensin II type 1 receptor (AT1R and analyzed how each receptor affected the angiotensin II (AngII response. To monitor the effect we used integrative receptor activation/signaling assay called Receptor Selection and Amplification Technology (R-SAT. In this screen the thromboxane A2α receptor (TPαR was the only receptor which significantly enhanced the AngII-mediated response. The TPαR-mediated enhancement of AngII signaling was significantly reduced when a signaling deficient receptor mutant (TPαR R130V was co-expressed instead of the wild-type TPαR, and was completely blocked both by TPαR antagonists and COX inhibitors inhibiting formation of thromboxane A2 (TXA2. CONCLUSIONS/SIGNIFICANCE: We found a functional enhancement of AT1R only when co-expressed with TPαR, but not with 122 other 7TM receptors. In addition, the TPαR must be functionally active, indicating the AT1R enhancement is mediated by a paracrine mechanism. Since we only found one receptor enhancing AT1R potency, our results suggest that functional augmentation through 7TM receptor cross-talk is a rare event that may require specific conditions to occur.

  4. Suppressor screen and phenotype analyses revealed an emerging role of the Monofunctional peroxisomal enoyl-CoA hydratase 2 in compensated cell enlargement

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    Mana eKatano

    2016-02-01

    Full Text Available Efficient use of seed nutrient reserves is crucial for germination and establishment of plant seedlings. Mobilizing seed oil reserves in Arabidopsis involves β-oxidation, the glyoxylate cycle, and gluconeogenesis, which provide essential energy and the carbon skeletons needed to sustain seedling growth until photoautotrophy is acquired. We demonstrated that H+-PPase activity is required for gluconeogenesis. Lack of H+-PPase in fugu5 mutants increases cytosolic pyrophosphate (PPi levels, which partially reduces sucrose synthesis de novo and inhibits cell division. In contrast, post-mitotic cell expansion in cotyledons was unusually enhanced, a phenotype called compensation. Therefore, it appears that PPi inhibits several cellular functions, including cell cycling, to trigger compensated cell enlargement (CCE. Here, we mutagenized fugu5-1 seeds with 12C6+ heavy-ion irradiation and screened mutations that restrain CCE to gain insight into the genetic pathway(s involved in CCE. We isolated A#3-1, in which cell size was severely reduced, but cell number remained similar to that of original fugu5-1. Moreover, cell number decreased in A#3-1 single mutant (A#3-1sm, similar to that of fugu5-1, but cell size was almost equal to that of the wild type. Surprisingly, A#3-1 mutation did not affect CCE in other compensation exhibiting mutant backgrounds, such as an3-4 and fugu2-1/fas1-6. Subsequent map-based cloning combined with genome sequencing and HRM curve analysis identified enoyl-CoA hydratase 2 (ECH2 as the causal gene of A#3-1. The above phenotypes were consistently observed in the ech2-1 allele and supplying sucrose restored the morphological and cellular phenotypes in fugu5-1, ech2-1, A#3-1sm, fugu5-1 ech2-1 and A#3-1;fugu5-1. Taken together, these results suggest that defects in either H+-PPase or ECH2 compromise cell proliferation due to defects in mobilizing stored lipids. In contrast, ECH2 alone likely promotes CCE during the post-mitotic cell

  5. Hippo, TGF-β, and Src-MAPK pathways regulate transcription of the upd3 cytokine in Drosophila enterocytes upon bacterial infection.

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    Houtz, Philip; Bonfini, Alessandro; Liu, Xi; Revah, Jonathan; Guillou, Aurélien; Poidevin, Mickael; Hens, Korneel; Huang, Hsin-Yi; Deplancke, Bart; Tsai, Yu-Chen; Buchon, Nicolas

    2017-11-01

    Cytokine signaling is responsible for coordinating conserved epithelial regeneration and immune responses in the digestive tract. In the Drosophila midgut, Upd3 is a major cytokine, which is induced in enterocytes (EC) and enteroblasts (EB) upon oral infection, and initiates intestinal stem cell (ISC) dependent tissue repair. To date, the genetic network directing upd3 transcription remains largely uncharacterized. Here, we have identified the key infection-responsive enhancers of the upd3 gene and show that distinct enhancers respond to various stresses. Furthermore, through functional genetic screening, bioinformatic analyses and yeast one-hybrid screening, we determined that the transcription factors Scalloped (Sd), Mothers against dpp (Mad), and D-Fos are principal regulators of upd3 expression. Our study demonstrates that upd3 transcription in the gut is regulated by the activation of multiple pathways, including the Hippo, TGF-β/Dpp, and Src, as well as p38-dependent MAPK pathways. Thus, these essential pathways, which are known to control ISC proliferation cell-autonomously, are also activated in ECs to promote tissue turnover the regulation of upd3 transcription.

  6. [Neonatal bacterial infection by maternal-fetal contamination: for a change in approach? 1. Detection of Streptococcus agalactiae infection: methods and evaluation of results].

    Science.gov (United States)

    Blond, M H; Gold, F; Pierre, F; Quentin, R; Aujard, Y

    2001-10-01

    Perinatal group B streptococcal infection has been the subject of numerous studies and despite guidelines established during the last decade remains a frequent disease with high mortality. The basic aim of the guidelines is to screen for Streptococcus agalactiae during the antepartum period in order to institute antibiotic therapy during delivery. A critical review of the literature highlights the real impact and adverse effect of these guidelines: difficult application (only two-thirds of all maternity units have a protocol and compliance is only 75%), maternal risks of antibiotic therapy (especially the emergence of resistant Gram negative bacteria), fetal risks (accentuation of neonatal sepsis with resistant strains, retarded neonatal infections, frequent use of antibiotics with a broader spectrum, higher frequency of nosocomial sepsis).

  7. High-sensitivity virus and mycoplasma screening test reveals high prevalence of parvovirus B19 infection in human synovial tissues and bone marrow.

    Science.gov (United States)

    Watanabe, Ken; Otabe, Koji; Shimizu, Norio; Komori, Keiichirou; Mizuno, Mitsuru; Katano, Hisako; Koga, Hideyuki; Sekiya, Ichiro

    2018-03-27

    Latent microorganism infection is a safety concern for the clinical application of mesenchymal stem cells (MSCs). The aim of this study is to investigate the frequencies and sensitivities of the latent virus and mycoplasma infections in synovium, bone marrow, peripheral blood cells, and blood plasma and cultured synovial MSCs. Total DNA and RNA of the synovium (n = 124), bone marrow (n = 123), peripheral blood cells (n = 121), plasma (n = 121), and 14-day cultured synovial MSCs (n = 63) were collected from patients who underwent total knee arthroplasty or anterior ligament reconstruction after written informed consents were obtained. The multiplex polymerase chain reaction (PCR) primers were designed to quantitatively measure the representative genomes of 13 DNA viruses, 6 RNA viruses, and 9 mycoplasmas. Multi-spliced mRNA detection and virus spike test were also performed to demonstrate the sensitivity of synovial MSCs to the candidate pathogens. In synovium and bone marrow, the positive rates of parvovirus B19 genome were significantly higher than in peripheral blood cells (18.7% and 22% vs. 0.8%, respectively). Multi-alignment analysis of amplified and sequenced viral target genes showed the proximity of the parvovirus B19 gene from different tissue in the same patients. Synovial MSCs cultured for 14 days were positive for virus infection only in two patients (2/62 = 3%). Parvovirus B19 multi-spliced mRNAs were not detected in these two samples. Virus spike test demonstrated the sensitivity of synovial MSCs to herpes simplex virus (HSV)1 and cytomegalovirus (CMV), but not to parvovirus B19. This study revealed a relatively high incidence of latent parvovirus B19 in synovium and bone marrow tissue.

  8. Pharmacophore-based screening of differentially-expressed PGF, DDIT4, COMP and CHI3L1 from hMSC cell lines reveals five novel therapeutic compounds for primary osteoporosis

    Directory of Open Access Journals (Sweden)

    Catherine Jessica Lai

    2016-06-01

    Full Text Available As many societies age, primary osteoporosis (PO is increasingly a major health problem. Current drug treatments such as alendronate and risedronate have known side effects. We took an agnostic empirical approach to find PO therapeutic compounds. We examined 13,548,960 probe data-points from mesenchymal stromal cell (hMSC lines and found that PGF, DDIT4, and COMP to be up-regulated, and CHI3L1, down-regulated. We then identified their druggable domains. For the up-regulated differentially-expressed genes, we used protein–protein interactions to find residue clusters as binding surfaces. We then employed pharmacophore models to screen 15,407,096 conformations of 22,723,923 compounds, which identified (6R,9R-6-(2-furyl-9-(1H-indol-3-yl-2-(trifluoromethyl-5,6,7, 9-tetrahydro-4H[1,2,4]triazolo[5,1],(2S-N1-[2-[2-(methylamino-2-oxo-ethyl]phenyl]-N2-phenylpyrrolidine-1,2-dicarboxamide, and 2-furyl-(1H-indol-3-yl-methyl-BLAHone as candidate compounds. For the down-regulated CH13L1, we relied on genome-wide disease signatures to identify (11alpha-9-fluoro-11,17,21-trihydroxypregn-4-ene-3,20-dione and Genistein as candidate compounds. Our approach differs from previous research as we did not confine our drug targets to hypothesized compounds in the existing literature. Instead, we allowed the full expression profile of PO cell lines to reveal the most desirable targets. Second, our differential gene analysis revealed both up- and down-regulated genes, in contrast to the literature, which has focused on inhibiting only up-regulated genes. Third, our virtual screening universe of 22,723,923 compounds was more than 100 times larger than those in the known literature.

  9. Prevalence of Sexually Transmitted Viral and Bacterial Infections in HIV-Positive and HIV-Negative Men Who Have Sex with Men in Toronto.

    Directory of Open Access Journals (Sweden)

    Robert S Remis

    Full Text Available Hepatitis B (HBV, hepatitis C (HCV and other sexually transmitted infections (STIs have been associated with HIV transmission risk and disease progression among gay men and other men who have sex with men (MSM, but the frequency and distribution of STIs in this community in Canada has not been extensively studied.We recruited MSM living with and without HIV from a large primary care clinic in Toronto. Participants completed a detailed socio-behavioural questionnaire using ACASI and provided blood for syphilis, HIV, HBV and HCV, herpes simplex virus type 1 (HSV-1 and type 2 (HSV-2, and human cytomegalovirus (CMV serology, urine for chlamydia and gonorrhea, and a self-collected anal swab for human papillomavirus (HPV molecular diagnostics. Prevalences were expressed as a proportion and compared using chi-square.442 MSM were recruited, 294 living with HIV and 148 without. Active syphilis (11.0% vs. 3.4%, ever HBV (49.4% vs. 19.1%, HCV (10.4% vs. 3.4%, HSV-2 (55.9% vs. 38.2%, CMV (98.3% vs. 80.3% and high-risk (HR anal HPV (67.6% vs. 51.7% infections were significantly more common in men living with HIV. Chlamydia and gonorrhea were infrequent in both groups. Regardless of HIV infection status, age and number of lifetime male sexual partners were associated with HBV infection and lifetime injection drug use with HCV infection.Syphilis and viral infections, including HBV, HCV, HSV-2, CMV, and HR-HPV, were common in this clinic-based population of MSM in Toronto and more frequent among MSM living with HIV. This argues for the implementation of routine screening, vaccine-based prevention, and education programs in this high-risk population.

  10. Ex vivo and in vivo evaluation of microemulsion based transdermal delivery of E. coli specific T4 bacteriophage: A rationale approach to treat bacterial infection.

    Science.gov (United States)

    Rastogi, Vaibhav; Yadav, Pragya; Verma, Anurag; Pandit, Jayanta K

    2017-09-30

    This study is focused on the development and evaluation of transdermal delivery of E. coli-specific T4 bacteriophages both ex-vivo and in-vivo using microemulsion as delivery carrier in eradicating the infection caused by E. coli. Microemulsions were prepared by mixing selected oil, surfactants and aqueous phase containing bacteriophages. The formulations were subjected to physicochemical characterization, ex-vivo and in-vivo permeation, stability studies, histological and immunofluorescence examination. The colloidal system exhibits a uniform size distribution, of finite size (150-320nm). Transmission electron microscopy revealed the encapsulation of bacteriophage in the aqueous globule. Ex-vivo permeation across skin was successfully achieved as 6×10 6 PFU/mL and 6.7×10 6 PFU/mL of T4 permeated from ME 6% and 10%, respectively. ME 6% was found to be thermodynamically stable and in-vivo permeation resulted in 5.49×10 5 PFU/mL of bacteriophages in the blood of the E. coli challenged rats, while 2.48×10 5 PFU/mL was detected in germ free rats, at the end of the study. Infected rats that were treated with bacteriophage were survived while significant mortality was observed in others. Histological and IL-6 immunofluorescence examination of the tissues revealed the efficacy/safety of the therapy. The microemulsion-based transdermal delivery of bacteriophage could be a promising approach to treat the infections caused by antibiotic-resistant bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Fragment library screening identifies hits that bind to the non-catalytic surface of Pseudomonas aeruginosa DsbA1

    Science.gov (United States)

    Headey, Stephen J.; Vazirani, Mansha; Shouldice, Stephen R.; Coinçon, Mathieu; Tay, Stephanie; Morton, Craig J.; Simpson, Jamie S.; Martin, Jennifer L.

    2017-01-01

    At a time when the antibiotic drug discovery pipeline has stalled, antibiotic resistance is accelerating with catastrophic implications for our ability to treat bacterial infections. Globally we face the prospect of a future when common infections can once again kill. Anti-virulence approaches that target the capacity of the bacterium to cause disease rather than the growth or survival of the bacterium itself offer a tantalizing prospect of novel antimicrobials. They may also reduce the propensity to induce resistance by removing the strong selection pressure imparted by bactericidal or bacteriostatic agents. In the human pathogen Pseudomonas aeruginosa, disulfide bond protein A (PaDsbA1) plays a central role in the oxidative folding of virulence factors and is therefore an attractive target for the development of new anti-virulence antimicrobials. Using a fragment-based approach we have identified small molecules that bind to PaDsbA1. The fragment hits show selective binding to PaDsbA1 over the DsbA protein from Escherichia coli, suggesting that developing species-specific narrow-spectrum inhibitors of DsbA enzymes may be feasible. Structures of a co-complex of PaDsbA1 with the highest affinity fragment identified in the screen reveal that the fragment binds on the non-catalytic surface of the protein at a domain interface. This biophysical and structural data represent a starting point in the development of higher affinity compounds, which will be assessed for their potential as selective PaDsbA1 inhibitors. PMID:28346540

  12. TPL-2-ERK1/2 signaling promotes host resistance against intracellular bacterial infection by negative regulation of type I IFN production.

    Science.gov (United States)

    McNab, Finlay W; Ewbank, John; Rajsbaum, Ricardo; Stavropoulos, Evangelos; Martirosyan, Anna; Redford, Paul S; Wu, Xuemei; Graham, Christine M; Saraiva, Margarida; Tsichlis, Philip; Chaussabel, Damien; Ley, Steven C; O'Garra, Anne

    2013-08-15

    Tuberculosis, caused by Mycobacterium tuberculosis, remains a leading cause of mortality and morbidity worldwide, causing ≈ 1.4 million deaths per year. Key immune components for host protection during tuberculosis include the cytokines IL-12, IL-1, and TNF-α, as well as IFN-γ and CD4(+) Th1 cells. However, immune factors determining whether individuals control infection or progress to active tuberculosis are incompletely understood. Excess amounts of type I IFN have been linked to exacerbated disease during tuberculosis in mouse models and to active disease in patients, suggesting tight regulation of this family of cytokines is critical to host resistance. In addition, the immunosuppressive cytokine IL-10 is known to inhibit the immune response to M. tuberculosis in murine models through the negative regulation of key proinflammatory cytokines and the subsequent Th1 response. We show in this study, using a combination of transcriptomic analysis, genetics, and pharmacological inhibitors, that the TPL-2-ERK1/2 signaling pathway is important in mediating host resistance to tuberculosis through negative regulation of type I IFN production. The TPL-2-ERK1/2 signaling pathway regulated production by macrophages of several cytokines important in the immune response to M. tuberculosis as well as regulating induction of a large number of additional genes, many in a type I IFN-dependent manner. In the absence of TPL-2 in vivo, excess type I IFN promoted IL-10 production and exacerbated disease. These findings describe an important regulatory mechanism for controlling tuberculosis and reveal mechanisms by which type I IFN may promote susceptibility to this important disease.

  13. fundTPL-2 – ERK1/2 Signaling Promotes Host Resistance against Intracellular Bacterial Infection by Negative Regulation of Type I Interferon Production3

    Science.gov (United States)

    McNab, Finlay W.; Ewbank, John; Rajsbaum, Ricardo; Stavropoulos, Evangelos; Martirosyan, Anna; Redford, Paul S.; Wu, Xuemei; Graham, Christine M.; Saraiva, Margarida; Tsichlis, Philip; Chaussabel, Damien; Ley, Steven C.; O’Garra, Anne

    2013-01-01

    Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of mortality and morbidity worldwide, causing approximately 1.4 million deaths per year. Key immune components for host protection during tuberculosis include the cytokines IL-12, IL-1 and TNF-α, as well as IFN-γ and CD4+ Th1 cells. However, immune factors determining whether individuals control infection or progress to active tuberculosis are incompletely understood. Excess amounts of type I interferon have been linked to exacerbated disease during tuberculosis in mouse models and to active disease in patients, suggesting tight regulation of this family of cytokines is critical to host resistance. In addition, the immunosuppressive cytokine IL-10 is known to inhibit the immune response to Mtb in murine models through the negative regulation of key pro-inflammatory cytokines and the subsequent Th1 response. We show here, using a combination of transcriptomic analysis, genetics and pharmacological inhibitors that the TPL-2-ERK1/2 signaling pathway is important in mediating host resistance to tuberculosis through negative regulation of type I interferon production. The TPL-2-ERK1/2 signalling pathway regulated production by macrophages of several cytokines important in the immune response to Mtb as well as regulating induction of a large number of additional genes, many in a type I IFN dependent manner. In the absence of TPL-2 in vivo, excess type I interferon promoted IL-10 production and exacerbated disease. These findings describe an important regulatory mechanism for controlling tuberculosis and reveal mechanisms by which type I interferon may promote susceptibility to this important disease. PMID:23842752

  14. Serum amyloid A and C-reactive protein combined determination for diagnosis of bacterial infection in neonates%血清淀粉样蛋白A与C反应蛋白联合检测在新生儿细菌感染诊断中的应用

    Institute of Scientific and Technical Information of China (English)

    沈伟虹; 岳朝艳; 孙振东; 应春妹

    2016-01-01

    目的:研究血清淀粉样蛋白 A(SAA)和 C 反应蛋白(CRP)以及白细胞总数在新生儿细菌感染诊断中的应用价值。方法分别检测80例细菌感染新生儿及58名体检正常的新生儿(非感染组)SAA、CRP 和白细胞总数并做比较。结果新生儿细菌感染组 SAA 与 CRP 水平分别为(67.3±38.4)、(19.2±11.2)mg/L,明显高于非感染组[(8.7±2.1)、(5.6±2.5)mg/L](P15.00×109/L,明显高于非感染组[24例(41%)]。结论 SAA 和 CRP 可作为新生儿细菌感染诊断的重要指标,SAA 较 CRP 更为敏感,SAA 与 CRP 的联合检测能够提高新生儿细菌感染的检出率,为疾病的早期诊断和监测提供实验依据。%Objective To study the significance of serum amyloid A(SAA),C-reactive protein(CRP)and white blood cell count determinations for diagnosis of bacterial infection in neonates. Methods SAA,CRP and white blood cell count were determined in 80 neonates with bacterial infection and 58 healthy neonates(non-bacterial infection group),and the results were analyzed. Results The concentrations of SAA and CRP in infection group [(67.3±38.4)and(19.2±11.2) mg/L] were significantly higher than those in non-bacterial infection group [(8.7±2.1)and(5.6±2.5)mg/L](P15.00×109/L in 64 neonates of 80 cases of infection group(80%),which was higher than that in non-bacterial infection group [24 cases(41%)]. Conclusions SAA and CRP could be used as important markers for monitoring bacterial infection in neonates,and SAA is more sensitive than CRP. The combined determination of SAA and CRP could improve the determination rate of bacterial infection,which provides an experimental reference for early diagnosis and monitoring of bacterial infection.

  15. Toxicology screen

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003578.htm Toxicology screen To use the sharing features on this page, please enable JavaScript. A toxicology screen refers to various tests that determine the ...

  16. Classification of human pathogen bacteria for early screening using electronic nose

    Science.gov (United States)

    Zulkifli, Syahida Amani; Mohamad, Che Wan Syarifah Robiah; Abdullah, Abu Hassan

    2017-10-01

    This paper present human pathogen bacteria for early screening using electronic nose. Electronic nose (E-nose) known as gas sensor array is a device that analyze the odor measurement give the fast response and less time consuming for clinical diagnosis. Many bacterial pathogens could lead to life threatening infections. Accurate and rapid diagnosis is crucial for the successful management of these infections disease. The conventional method need more time to detect the growth of bacterial. Alternatively, the bacteria are Pseudomonas aeruginosa and Shigella cultured on different media agar can be detected and classifies according to the volatile compound in shorter time using electronic nose (E-nose). Then, the data from electronic nose (E-nose) is processed using statistical method which is principal component analysis (PCA). The study shows the capability of electronic nose (E-nose) for early screening for bacterial infection in human stomach.

  17. Evaluation of anti-peptidoglycan aptamers labeled with Technetium-99m for in vivo bacterial infection identification; Avaliacao de aptameros anti-peptidoglicano marcados com Tecnecio-99m para identificacao in vivo de infecoes bacterianas

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ieda Mendes

    2017-07-01

    Aptamers are oligonucleotides that display high affinity and specificity for their molecular targets and are emerging as promising molecules for radiopharmaceuticals development. In a previous work, we selected two aptamers for peptidoglycan (the main constituent of bacterial cell walls) termed Antibac1 and Antibac2. In the present study, the characterization of these aptamers was completed, and the dissociation coefficients (K{sub d}) were determined. The aptamers were further labeled with {sup 99m}Tc and evaluated for bacterial infection diagnosis by scintigraphy. The K{sub d} obtained for Antibac1 was of 0.415 ± 0.047 μM and for Antibac2 of 1.261 ± 0.280 μM. The direct labeling method with {sup 99m}Tc allowed radiolabel yields higher than 90% and the radiolabel stability in saline, plasma and cysteine excess indicated that the process was suitable for labeling of both aptamers. The {sup 99m}Tc-aptamers are prone to bind to plasma proteins: 39.5% ± 2.9% (1 h) and 43.6% ± 1.2% (3 h) for {sup 99m}Tc-Antibac1; 37.6% ± 2.0% (1 h) and 40.9% ± 0% (3 h) for {sup 99m}Tc-Antibac2. The blood clearance half-life for {sup 99m}Tc-Antibac1 was of 41.26 min and for the {sup 99m}Tc-Antibac2 of 31.58 min. The {sup 99m}Tc-Antibac1 in the group infected with S. aureus presented a target/non-target ratio of 2.81 ± 0.67, significantly higher than verified for the {sup 99m}Tc-library (control): 1.52 ± 0.07. In the model with C. albicans infection the target/non-target ratio for {sup 99m}Tc-Antibac1 was 1.46 ± 0.11, similar that obtained for the {sup 99m}Tc-library in the same model: 1.52 ± 0.05. The {sup 99m}Tc-Antibac2 in the group infected with S. aureus showed a target/non-target ratio of 2.61 ± 0.66, statistically higher than achieved for the {sup 99m}Tc-library in the same infection model: 1.52 ± 0.07. In the group infected with C. albicans this ratio for {sup 99m}Tc-Antibac2 was 1.75 ± 0.19, it was significantly higher than verified for the {sup 99m}Tc-library: 1

  18. Respiratory bacterial infections in cystic fibrosis

    DEFF Research Database (Denmark)

    Ciofu, Oana; Hansen, Christine R; Høiby, Niels

    2013-01-01

    PURPOSE OF REVIEW: Bacterial respiratory infections are the main cause of morbidity and mortality in patients with cystic fibrosis (CF). Pseudomonas aeruginosa remains the main pathogen in adults, but other Gram-negative bacteria such as Achromobacter xylosoxidans and Stenotrophomonas maltophilia...... respiratory tract (nasal sampling) should be investigated and both infection sites should be treated....

  19. Secondary Bacterial Infections Associated with Influenza Pandemics

    Science.gov (United States)

    Morris, Denise E.; Cleary, David W.; Clarke, Stuart C.

    2017-01-01

    Lower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012). Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic. PMID:28690590

  20. Secondary Bacterial Infections Associated with Influenza Pandemics

    Directory of Open Access Journals (Sweden)

    Denise E. Morris

    2017-06-01

    Full Text Available Lower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012. Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic.

  1. Bacterial infections associated with allogenic bone transplantation

    Directory of Open Access Journals (Sweden)

    Stepanović Željko Lj.

    2015-01-01

    Full Text Available Background/Aim. Bone allografts are frequently used in orthopedic reconstructive procedures carrying a high risk for recipients. To assess the nature and frequency of allograft contamination and associated surgical infection the case records from our institutional bone bank were reviewed. Methods. We retrospectively analyzed the microbiology of discarded bone allografts and the surgical site of the recipients. A case series of patients who acquired surgical site infection after allogenic bone transplantation was presented. Swab culturing was conducted on 309 femoral heads from living donors who underwent partial and total hip arthroplasty between January 2007 and December 2013. To prevent potential bone allograft contamination we used saline solution of 2.0 mg/ml of amikacin during thawing. The overall infection rate was analyzed in 197 recipients. Results. Of the 309 donated femoral heads, 37 were discarded due to bacterial contamination, giving the overall contamination rate of 11.97%. The postoperative survey of 213 bone allotransplantations among 197 recipients showed the infection rate of 2.03%. The coagulase-negative Staphylococcus was the most commonly identified contaminant of bone allografts and recipient surgical sites. Conclusion. The allograft contamination rate and the infection rate among recipients in our institution are in accordance with the international standards. The coagulase-negative Staphylococcus was the most commonly identified contaminant of bone allografts and recipient surgical sites. There is no strong evidence that surgical site infections were associated with bone allograft utilization. We plan further improvements in allograft handling and decontamination with highly concentrated antibiotic solutions in order to reduce infection risk for recipients.

  2. Mucin dynamics in intestinal bacterial infection.

    Directory of Open Access Journals (Sweden)

    Sara K Lindén

    Full Text Available Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract.Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17 in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05. Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon.Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection.

  3. Defining the origins of electron transfer at screen-printed graphene-like and graphite electrodes: MoO2 nanowire fabrication on edge plane sites reveals electrochemical insights.

    Science.gov (United States)

    Rowley-Neale, Samuel J; Brownson, Dale A C; Banks, Craig E

    2016-08-18

    Molybdenum (di)oxide (MoO2) nanowires are fabricated onto graphene-like and graphite screen-printed electrodes (SPEs) for the first time, revealing crucial insights into the electrochemical properties of carbon/graphitic based materials. Distinctive patterns observed in the electrochemical process of nanowire decoration show that electron transfer occurs predominantly on edge plane sites when utilising SPEs fabricated/comprised of graphitic materials. Nanowire fabrication along the edge plane sites (and on edge plane like-sites/defects) of graphene/graphite is confirmed with Cyclic Voltammetry, Scanning Electron Microscopy (SEM) and Raman Spectroscopy. Comparison of the heterogeneous electron transfer (HET) rate constants (k°) at unmodified and nanowire coated SPEs show a reduction in the electrochemical reactivity of SPEs when the edge plane sites are effectively blocked/coated with MoO2. Throughout the process, the basal plane sites of the graphene/graphite electrodes remain relatively uncovered; except when the available edge plane sites have been utilised, in which case MoO2 deposition grows from the edge sites covering the entire surface of the electrode. This work clearly illustrates the distinct electron transfer properties of edge and basal plane sites on graphitic materials, indicating favourable electrochemical reactivity at the edge planes in contrast to limited reactivity at the basal plane sites. In addition to providing fundamental insights into the electron transfer properties of graphite and graphene-like SPEs, the reported simple, scalable, and cost effective formation of unique and intriguing MoO2 nanowires realised herein is of significant interest for use in both academic and commercial applications.

  4. Colon cancer screening

    Science.gov (United States)

    Screening for colon cancer; Colonoscopy - screening; Sigmoidoscopy - screening; Virtual colonoscopy - screening; Fecal immunochemical test; Stool DNA test; sDNA test; Colorectal cancer - screening; Rectal ...

  5. Phytochemical screening and antiproliferative effects of methanol ...

    African Journals Online (AJOL)

    Preliminary Phytochemical screening. Thin layer chromatographic profile (TLC) of methanol crude extract and antiproliferative studies were carried out in this research. Phytochemical screening revealed the presence of carbohydrate, glycoside, anthraquinone, steroid, triterpenes, saponin, tannins, flavonoids and alkaloid.

  6. Breast Cancer Screening

    International Nuclear Information System (INIS)

    Altaf, Fadwa J.

    2004-01-01

    Breast cancer is a very common health problem in Saudi females that can be reduced by early detection through introducing breast cancer screening. Literature review reveals significant reduction in breast cancer incidence and outcome after the beginning of breast cancer screening. The objectives of this article are to highlight the significance of breast cancer screening in different international societies and to write the major guidelines of breast cancer screening in relation to other departments involved with more emphasis on the Pathology Department guidelines in tissue handling, diagnostic criteria and significance of the diagnosis. This article summaries and acknowledges major work carried out before, and recommends similar modified work in order to meet the requirement for the Saudi society. (author)

  7. Synthesis and Characterization of Protein-Conjugated Silver Nanoparticles/Silver Salt Loaded Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Film for Prevention of Bacterial Infections and Potential Use in Bone Tissue Engineering Applications

    Science.gov (United States)

    Bakare, Rotimi Ayotunde

    Failure of orthopedic implants due to bacterial infection has been a major concern in bone tissue engineering. To this end, we have formulated a potential orthopedic implant made of naturally occurring biodegradable polymer, i.e. poly (3-hydroxylbutyrate-co-3-hydroxylvalerate) (PHBV), modified with BSA conjugated silver nanoparticles and or silver chloride. Upon release of Ag NPs and or Ag+ in the implant region, can promote aseptic environment by inhibition of bacteria growth and also support/maintain bone cell adhesion, growth, and proliferation. For formulating nanoparticles loaded PHBV scaffold, we exploit specific interaction between bovine serum albumin (BSA) of BSA capped silver nanoparticles and collagen of collagen immobilized PHBV scaffold. Therefore, the first part of this study dealt with synthesis and characterization of collagen immobilized PHBV film for loading of BSA stabilized silver (Ag/BSA) nanoparticles. Two different approaches were used to immobilize collagen on macroporous PHBV film. First approach uses thermal radical copolymerization with 2-hydroxyethylmethacrylate (HEMA), while the second approach uses aminolysis to functionalize macroporous PHBV film. Using collagen crosslinker, type I collagen was covalently grafted to formulate collagen immobilized PHEMA-g-PHBV and collagen immobilized NH2-PHBV films, respectively. Spectroscopic (FTIR, XPS), physical (SEM), and thermal (TGA) techniques were used to characterize the functionalized PHBV films. The Ag/BSA nanoparticles were then loaded on collagen immobilized PHBV films and untreated PHBV films. The concentration of nanoparticles loaded on PHBV film was determined by atomic absorption spectrometry and fluorescence spectroscopy. The amount of nanoparticles loaded on collagen immobilized PHBV film was found to be significantly greater than that on untreated PHBV film. The amount of Ag/BSA nanoparticles loaded on collagen immobilized PHBV film was found to depend on the concentration of Ag

  8. RAS - Screens & Assays - Drug Discovery

    Science.gov (United States)

    The RAS Drug Discovery group aims to develop assays that will reveal aspects of RAS biology upon which cancer cells depend. Successful assay formats are made available for high-throughput screening programs to yield potentially effective drug compounds.

  9. Lung cancer screening: Update

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyea Young [Dept. of Radiology, Center for Lung Cancer, National Cancer Center, Goyang (Korea, Republic of)

    2015-09-15

    Lung cancer is the leading cause of cancer deaths worldwide as well as in Korea. A recent National Lung Screening Trial in U.S. revealed that low-dose CT (LDCT) screening reduced lung cancer specific mortality by 20% in high risk individuals as compared to chest radiograph screening. Based on this evidence, several expert societies in U.S. and Korean multisociety collaborative committee developed guidelines for recommendation of lung cancer screening using annual LDCT in high risk populations. In most of the societies high risk groups are defined as persons aged 55 to 74 years, who are current smokers with history of smoking of more than 30 packs per year or ex-smokers, who quit smoking up to 15 or more years ago. The benefits of LDCT screening are modestly higher than the harms in high risk individuals. The harms included a high rate of false-positive findings, over-diagnosis and radiation-related deaths. Invasive diagnostic procedure due to false positive findings may lead to complications. LDCT should be performed in qualified hospitals and interpreted by expert radiologists. Recently, the American College of Radiology released the current version of Lung cancer CT screening Reporting and Data Systems. Education and actions to stop smoking must be offered to current smokers.

  10. Lung cancer screening: Update

    International Nuclear Information System (INIS)

    Kim, Hyea Young

    2015-01-01

    Lung cancer is the leading cause of cancer deaths worldwide as well as in Korea. A recent National Lung Screening Trial in U.S. revealed that low-dose CT (LDCT) screening reduced lung cancer specific mortality by 20% in high risk individuals as compared to chest radiograph screening. Based on this evidence, several expert societies in U.S. and Korean multisociety collaborative committee developed guidelines for recommendation of lung cancer screening using annual LDCT in high risk populations. In most of the societies high risk groups are defined as persons aged 55 to 74 years, who are current smokers with history of smoking of more than 30 packs per year or ex-smokers, who quit smoking up to 15 or more years ago. The benefits of LDCT screening are modestly higher than the harms in high risk individuals. The harms included a high rate of false-positive findings, over-diagnosis and radiation-related deaths. Invasive diagnostic procedure due to false positive findings may lead to complications. LDCT should be performed in qualified hospitals and interpreted by expert radiologists. Recently, the American College of Radiology released the current version of Lung cancer CT screening Reporting and Data Systems. Education and actions to stop smoking must be offered to current smokers

  11. Screen dealing

    International Nuclear Information System (INIS)

    Barlow, J.W.

    1991-01-01

    The screen dealing system provides a facility whereby buyers and sellers of spot thermal coal can make bids and offers via the medium of the Reuters screen. A sale results when a market participant notifies his acceptance of a price to a central dealing desk. Use of the system is available to all genuine participants in the coal trade. This paper reports that it provides a focus for information and for the visible making of coal prices. For years screen trading has been used successfully to trade other commodities. At last coal is being traded electronically. It makes sense. It works. Users like it

  12. Airport Screening

    Science.gov (United States)

    Health Physics Society Specialists in Radiation Safety Airport Screening Fact Sheet Adopted: May 2011 Photo courtesy of Dan ... a safe level. An American National Standards Institute/Health Physics Society industry standard states that the maxi- mum ...

  13. Hypertension screening

    Science.gov (United States)

    Foulke, J. M.

    1975-01-01

    An attempt was made to measure the response to an announcement of hypertension screening at the Goddard Space Center, to compare the results to those of previous statistics. Education and patient awareness of the problem were stressed.

  14. Carrier Screening

    Science.gov (United States)

    ... How accurate is carrier screening? No test is perfect. In a small number of cases, test results ... in which an egg is removed from a woman’s ovary, fertilized in a laboratory with the man’s ...

  15. A Clinical Drug Library Screen Identifies Tosufloxacin as Being Highly Active against Staphylococcus aureus Persisters

    Directory of Open Access Journals (Sweden)

    Hongxia Niu

    2015-07-01

    Full Text Available To identify effective compounds that are active against Staphylococcus aureus (S. aureus persisters, we screened a clinical drug library consisting of 1524 compounds and identified six drug candidates that had anti-persister activity: tosufloxacin, clinafloxacin, sarafloxacin, doxycycline, thiostrepton, and chlorosalicylanilide. Among them, tosufloxacin had the highest anti-persister activity, which could completely eradicate S. aureus persisters within 2 days in vitro. Clinafloxacin ranked the second with very few persisters surviving the drug exposure. Interestingly, we found that both tosufloxacin and trovafloxacin that had high activity against persisters contained at the N-1 position the 2,4-difluorophenyl group, which is absent in other less active quinolones and may be associated with the high anti-persister activity. Further studies are needed to evaluate tosufloxacin in animal models and to explain its unique activity against bacterial persisters. Our findings may have implications for improved treatment of persistent bacterial infections.

  16. Screening of a Drug Library Identifies Inhibitors of Cell Intoxication by CNF1.

    Science.gov (United States)

    Mahtal, Nassim; Brewee, Clémence; Pichard, Sylvain; Visvikis, Orane; Cintrat, Jean-Christophe; Barbier, Julien; Lemichez, Emmanuel; Gillet, Daniel

    2018-04-06

    Cytotoxic necrotizing factor 1 (CNF1) is a toxin produced by pathogenic strains of Escherichia coli responsible for extra-intestinal infections. CNF1 deamidates Rac1, thereby triggering its permanent activation and worsening inflammatory reactions. Activated Rac1 is prone to proteasomal degradation. There is no targeted therapy against CNF1, despite its clinical relevance. In this work we developed a fluorescent cell-based immunoassay to screen for inhibitors of CNF1-induced Rac1 degradation among 1120 mostly approved drugs. Eleven compounds were found to prevent CNF1-induced Rac1 degradation, and five also showed a protective effect against CNF1-induced multinucleation. Finally, lasalocid, monensin, bepridil, and amodiaquine protected cells from both diphtheria toxin and CNF1 challenges. These data highlight the potential for drug repurposing to fight several bacterial infections and Rac1-based diseases. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Cuatro métodos de predicción de riesgo de infección bacteriana grave en recién nacidos febriles Four methods to predict the severe bacterial infection risk in the febrile newborns

    Directory of Open Access Journals (Sweden)

    Manuel Díaz Álvarez

    2010-12-01

    Full Text Available INTRODUCCIÓN. El objetivo de esta investigación fue contrastar la efectividad de 4 métodos de evaluación de riesgo de infección bacteriana grave (IBG en recién nacidos (RN febriles, uno de los cuales fue desarrollado por los autores del trabajo y los otros son los utilizados en la práctica internacional. MÉTODOS. Se realizó un estudio descriptivo, retrospectivo y aplicado de 1358 RN febriles sin signos de focalización evaluados y clasificados por riesgo de IBG. Fue aplicado el método propuesto por los autores, que comprende: antecedente de ser sano; ausencia de impresión médica de un estado tóxico-infeccioso; ausencia de evidencias de infección focal en el examen físico; fiebre menor de 39 ºC y no persistente o recurrente; recuento de leucocitos sanguíneos > 5,0 x 10(9/L y INTRODUCTION. The aim of present research was to contrast the effectiveness of four assessment methods of severe bacterial infection risk (SBI in febrile newborns (NB , one of above mentioned methods was developed by paper's authors and the other are used in the international practice. METHODS. A retrospective and descriptive study was conducted and applied in 1358 febrile NB with no focalization signs and classified according to the SBI. The method proposed by authors was applied including a history of be healthy, lack of medical criterion of a infectious-toxic state, lack of evidences of focal infection in physical examination, fever lower than 39°C and no persistent or recurrent, blood leucocytes count >5,0 x 10(9/L and < 20,0 x 10(9/L, globular sedimentation speed <20 mm/h and urine leucocyte count <10 000/mL. This method and the other were applied in a initial assessment and at the end of the evolution 48 h. The predictive values were estimated for the different methods and also the effectiveness was assessed according to the gain function. RESULTS. The SBI was of 20,4%. The more frequent cause was the urinary tract infection. From the 652 NB initially

  18. Luminescent screens

    International Nuclear Information System (INIS)

    Lu, C.-I.

    1982-01-01

    Luminescent screens which are useful for such purposes as intensifying screens for radiographs are comprised of a support bearing a layer of finely divided particles of a phosphor dispersed in a cross-linked polymeric matrix formed by heat-curing of a coating composition comprising an unsaturated cross-linkable polymer, a polymerizable acrylic monomer, a thermoplastic polyurethane elastomer, and a heat-activatable polymerization initiator. The phosphor layer includes voids formed by evaporation of an evaporable component which is present in the coating composition from which such layer is formed. (author)

  19. Alcohol Use Screening

    Science.gov (United States)

    ... Depression Screening Substance Abuse Screening Alcohol Use Screening Alcohol Use Screening (AUDIT-C) - Instructions The following questions ... this tool, there is also text-only version . Alcohol Use Screening (AUDIT-C) - Manual Instructions The following ...

  20. Hearing Screening

    Science.gov (United States)

    Johnson-Curiskis, Nanette

    2012-01-01

    Hearing levels are threatened by modern life--headsets for music, rock concerts, traffic noises, etc. It is crucial we know our hearing levels so that we can draw attention to potential problems. This exercise requires that students receive a hearing screening for their benefit as well as for making the connection of hearing to listening.

  1. Vision Screening

    Science.gov (United States)

    ... an efficient and cost-effective method to identify children with visual impairment or eye conditions that are likely to lead ... main goal of vision screening is to identify children who have or are at ... visual impairment unless treated in early childhood. Other problems that ...

  2. Nursing staff knowledge of multi-resistant bacterial infections Conocimiento de los profesionales de enfermería referente a la resistencia bacteriana a múltiples drogas Conhecimento dos profissionais de enfermagem referente à resistencia bacteriana a múltiplas drogas

    Directory of Open Access Journals (Sweden)

    Josely Pinto de Moura

    2007-09-01

    Full Text Available OBJECTIVE: To assess professional nurses', associate degree prepared nurses', licensed practical nurses', and nursing assistants' knowledge of the causes of multi-resistant bacterial infections, the risks theses infections pose to health care providers, the chain of transmission of these infections, and patients' susceptibility to colonization of these multi-resistant bacterial infections. METHODS: This descriptive study was conducted in a major general hospital in Minas Gerais, Brazil. The sample consisted of 42 nursing staff from a medical clinical unit. Descriptive statistics were used to analyze and present the data. RESULTS: Nursing staff had unsatisfactory knowledge of the causes of multi-resistant bacterial infections, the chain of transmission of multi-resistant bacterial infections, and patients' susceptibility to colonization of multi-resistant bacterial infections. However, the majority of participants had some knowledge about the risks that multi-resistant bacterial infections posed to health care providers. CONCLUSION: Lack of knowledge among nursing staff compromise adherence to preventive measures and nursing management of multi-resistant bacterial infections.OBJETIVO: Evaluar el conocimiento de los enfermeros, técnicos y auxiliares de enfermería de un hospital general de Minas Gerais, en cuanto a las causas da multirresistencia bacteriana, los riesgos para el equipo de salud, el modo de transmisión y susceptibilidad de los pacientes a la colonización por bacterias resistentes a múltiples drogas. MÉTODOS: Realizado en la clínica médica, fueron entrevistados 42 profesionales de enfermería encontrados en la unidad. En este estudio de tipo cuantitativo se realizó un análisis descriptivo de sus datos, utilizándose la estadística descriptiva con base en el cálculo de porcentaje, los cuales fueron presentados en tablas. RESULTADOS: Los profesionales demostraron conocimiento restricto y limitado sobre la tem

  3. Mathematics revealed

    CERN Document Server

    Berman, Elizabeth

    1979-01-01

    Mathematics Revealed focuses on the principles, processes, operations, and exercises in mathematics.The book first offers information on whole numbers, fractions, and decimals and percents. Discussions focus on measuring length, percent, decimals, numbers as products, addition and subtraction of fractions, mixed numbers and ratios, division of fractions, addition, subtraction, multiplication, and division. The text then examines positive and negative numbers and powers and computation. Topics include division and averages, multiplication, ratios, and measurements, scientific notation and estim

  4. Vision Screening

    Science.gov (United States)

    1993-01-01

    The Visi Screen OSS-C, marketed by Vision Research Corporation, incorporates image processing technology originally developed by Marshall Space Flight Center. Its advantage in eye screening is speed. Because it requires no response from a subject, it can be used to detect eye problems in very young children. An electronic flash from a 35 millimeter camera sends light into a child's eyes, which is reflected back to the camera lens. The photorefractor then analyzes the retinal reflexes generated and produces an image of the child's eyes, which enables a trained observer to identify any defects. The device is used by pediatricians, day care centers and civic organizations that concentrate on children with special needs.

  5. Antimicrobial screening of some medicinal plants from Mato Grosso Cerrado

    Directory of Open Access Journals (Sweden)

    Iberê E Silva Junior

    Full Text Available Hexane, dichloromethane, ethyl acetate and ethanol extracts from stem barks of Bowdichia virgilioides, Calophyllum brasiliense, Cariniana rubra, Lafoensia pacari, and Stryphnodendron obovatum and rhizome of Simaba ferruginea and Dragon's blood red sap from Croton urucurana were screened against a panel of bacteria and fungi using the micro-broth dilution method. Dragon's blood from Croton urucurana was the most effective antimicrobial plant material. Ethyl acetate and hexane extracts of Calophyllum brasiliense stem bark deserved distinction by their selective antibacterial activity. Lafoensia pacari stem bark polar extracts distinguished by their potent and selective anti-yeast activity and Bowdichia virgilioides polar and non-polar extracts by their antifungal activity towards hyalohypho-mycetes and dermatophytes. This is the first report showing antifungal activity for polar extracts of Cariniana rubra and Simaba ferruginea. This study has demonstrated antimicrobial activity of Mato Grosso Cerrado ethnomedicinal plants in in vitro assays and has indicated that they can be effective potential candidates for the development of new strategies to treat fungal and bacterial infections.

  6. Water screen

    Energy Technology Data Exchange (ETDEWEB)

    Kutepov, A.I.; Fedotov, I.N.; Prokopov, O.I.

    1981-01-01

    The invention refers to ventilation and can be used for repair-fitting operations in a blasting-dangerous gas condition, for example, during elimination of gas-oil gushers, repair of gas-oil pipelines, equipment etc. In order to improve safety of labor, the nozzle adapters of the water collector are oriented towards each other. The collector is installed on a support with the possibility of rotating and vertical movement. The proposed screen excludes the possibility of blasting-dangerous concentrations of gases and guarantees extinguishing of the impact spark during operation of the tool.

  7. RBC Antibody Screen

    Science.gov (United States)

    ... C Cystic Fibrosis (CF) Gene Mutations Testing Cytomegalovirus (CMV) Tests D-dimer Dengue Fever Testing Des-gamma- ... Index of Screening Recommendations Not Listed? Not Listed? Newborn Screening Screening Tests for Infants Screening Tests for ...

  8. Mental Health Screening Center

    Science.gov (United States)

    ... Releases & Announcements Public Service Announcements Partnering with DBSA Mental Health Screening Center These online screening tools are not ... you have any concerns, see your doctor or mental health professional. Depression Screening for Adult Depression Screening for ...

  9. Breast cancer screening

    Science.gov (United States)

    Mammogram - breast cancer screening; Breast exam - breast cancer screening; MRI - breast cancer screening ... is performed to screen women to detect early breast cancer when it is more likely to be cured. ...

  10. 眼底荧光造影检查对筛检糖尿病眼底病变的临床价值%Fundus Fluorescence Angiography Revealed the Clinical Value of Screening Diabetic Retinal Pathological Changes

    Institute of Scientific and Technical Information of China (English)

    王克

    2016-01-01

    Objective To explore the application value of fundus fluorescein angiography in screening of diabetic retinopa-thy. Methods Convenient selection who were admitted to our hospital in January 2013 to January 2016 By ophthalmoscopy and fundus fluorescence angiography 78 cases (156 eyes) in patients with diabetes mellitus retinopathy screening, according to Dr staging criteria for diagnosis of diabetic retinopathy staging, and thus as the foundation to give guidance of treatment. Results The detection rate of fundus fluorescein angiography in diabetic retinopathy (82.50%) was higher than that in the fundus examination (67.31%). The difference was statistically significant (P< 0.05). DR stage I period of 47 eyes (30.1%). II phase 29 eyes(18.6%), III phase 25 eyes(16%), IV phase 17 eyes(10.9%), V phase 7 eyes(4.5%), VI phase 3 eyes (1.9%). Conclusion The detection rate of fundus fluorescein angiography in diabetic retinopathy is high, which can be used as an important reference index to guide the treatment of ocular fundus diseases.%目的:探讨眼底荧光造影检查在糖尿病眼底病变筛查中的应用价值。方法方便选取2013年1月—2016年1月以眼底镜和眼底荧光造影检查该院收治的78例(156眼)糖尿病患者进行眼底病变筛查,依DR分期标准对筛查出的糖尿病视网膜病变进行分期,并以此为基础给予患者治疗指导。结果眼底荧光造影对糖尿病眼底病变的检出率显(82.50%)著高于眼底镜下检查(67.31%)。比较差异有统计学意义(P﹤0.05)。 DR分期I期47眼(30.1%)。 II期29眼(18.6%),III期25眼(16.0%),IV期17眼(10.9%),V期7眼(4.5%),VI期3眼(1.9%)。结论以眼底荧光造影筛查糖尿病眼底病变检出率高,可作为指导眼底病变治疗的重要参考指标在临床推广使用。

  11. Revealing Rembrandt

    Directory of Open Access Journals (Sweden)

    Andrew J Parker

    2014-04-01

    Full Text Available The power and significance of artwork in shaping human cognition is self-evident. The starting point for our empirical investigations is the view that the task of neuroscience is to integrate itself with other forms of knowledge, rather than to seek to supplant them. In our recent work, we examined a particular aspect of the appreciation of artwork using present-day functional magnetic resonance imaging (fMRI. Our results emphasised the continuity between viewing artwork and other human cognitive activities. We also showed that appreciation of a particular aspect of artwork, namely authenticity, depends upon the co-ordinated activity between the brain regions involved in multiple decision making and those responsible for processing visual information. The findings about brain function probably have no specific consequences for understanding how people respond to the art of Rembrandt in comparison with their response to other artworks. However, the use of images of Rembrandt’s portraits, his most intimate and personal works, clearly had a significant impact upon our viewers, even though they have been spatially confined to the interior of an MRI scanner at the time of viewing. Neuroscientific studies of humans viewing artwork have the capacity to reveal the diversity of human cognitive responses that may be induced by external advice or context as people view artwork in a variety of frameworks and settings.

  12. Pennsylvania's experience in mass screening

    International Nuclear Information System (INIS)

    Gerusky, T.M.

    1975-01-01

    A policy statement issued in 1972 by the Assistant Secretary for Health and Scientific Affairs of the Department of Health, Education, and Welfare recommended that community chest x-ray surveys should not be used as a screening procedure for the detection of cardiopulmonary disorders and that when chest x-ray screening programs are justified for selected population groups, the full size photograph, rather than the miniature film, is preferred. A survey conducted in 1974--75 revealed that chest x rays were required for prisoners, prison employees, school employees, food handlers, and students who wished to participate in sports. Meetings were held with medical associations in the hope of stopping the local mass-screening operations. Of 27 groups in Pennsylvania involved in tuberculosis screening, 12 groups refused or were unwilling to phase out their photofluorographic procedures. The problem will be resolved by regulation

  13. Proximate composition, phytochemical screening and antianaemic ...

    African Journals Online (AJOL)

    In this study, the phytochemical screening and anti-anaemic effect of Aloe barbadensis leaves was investigated in nutritionally stressed rats. Preliminary phytochemical screening test of the plant revealed that it contained tannins, flavonoids, anthraquinones, saponins, alkaloids and cardiac glycosides. Sets of male albino ...

  14. Phytochemical Screening, Antibacterial and Toxicological Activities ...

    African Journals Online (AJOL)

    The phytochemical screening, antibacterial and toxicological activities of extracts of the stem bark of Acacia senegal were investigated. The phytochemical analyses according to standard screening tests using conventional protocols revealed the presence of tannins, saponins and sterols in the stem bark of the plant.

  15. Skin Cancer Screening

    Science.gov (United States)

    ... Genetics of Skin Cancer Skin Cancer Screening Research Skin Cancer Screening (PDQ®)–Patient Version What is screening? ... These are called diagnostic tests . General Information About Skin Cancer Key Points Skin cancer is a disease ...

  16. Screening for Cancer

    Science.gov (United States)

    Cancer screening is checking for cancer in people who don't have symptoms. Screening tests can help doctors find and treat several types of cancer early, but cancer screening can have harms as well as benefits.

  17. Colorectal Cancer Screening

    Science.gov (United States)

    ... Genetics of Colorectal Cancer Colorectal Cancer Screening Research Colorectal Cancer Screening (PDQ®)–Patient Version What is screening? Go ... These are called diagnostic tests . General Information About Colorectal Cancer Key Points Colorectal cancer is a disease in ...

  18. Screen time and children

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000355.htm Screen time and children To use the sharing features on ... videos is considered unhealthy screen time. Current Screen Time Guidelines Children under age 2 should have no ...

  19. Stomach (Gastric) Cancer Screening

    Science.gov (United States)

    ... Stomach Cancer Prevention Stomach Cancer Screening Research Stomach (Gastric) Cancer Screening (PDQ®)–Patient Version What is screening? Go ... are called diagnostic tests . General Information About Stomach (Gastric) Cancer Key Points Stomach cancer is a disease in ...

  20. Prenatal screening and genetics

    DEFF Research Database (Denmark)

    Alderson, P; Aro, A R; Dragonas, T

    2001-01-01

    Although the term 'genetic screening' has been used for decades, this paper discusses how, in its most precise meaning, genetic screening has not yet been widely introduced. 'Prenatal screening' is often confused with 'genetic screening'. As we show, these terms have different meanings, and we...... examine definitions of the relevant concepts in order to illustrate this point. The concepts are i) prenatal, ii) genetic screening, iii) screening, scanning and testing, iv) maternal and foetal tests, v) test techniques and vi) genetic conditions. So far, prenatal screening has little connection...... with precisely defined genetics. There are benefits but also disadvantages in overstating current links between them in the term genetic screening. Policy making and professional and public understandings about screening could be clarified if the distinct meanings of prenatal screening and genetic screening were...

  1. Ethical issues in cancer screening and prevention.

    Science.gov (United States)

    Plutynski, Anya

    2012-06-01

    November 2009's announcement of the USPSTF's recommendations for screening for breast cancer raised a firestorm of objections. Chief among them were that the panel had insufficiently valued patients' lives or allowed cost considerations to influence recommendations. The publicity about the recommendations, however, often either simplified the actual content of the recommendations or bypassed significant methodological issues, which a philosophical examination of both the science behind screening recommendations and their import reveals. In this article, I discuss two of the leading ethical considerations at issue in screening recommendations: respect for patient autonomy and beneficence and then turn to the most significant methodological issues raised by cancer screening: the potential biases that may infect a trial of screening effectiveness, the problem of base rates in communicating risk, and the trade-offs involved in a judgment of screening effectiveness. These issues reach more broadly, into the use of "evidence-based" medicine generally, and have important implications for informed consent.

  2. Molecular screening in galactosemia

    Energy Technology Data Exchange (ETDEWEB)

    Elsas, L.J.; Singh, R.; Fernhoff, P.M. [Emory Univ., Atlanta, GA (United States)] [and others

    1994-09-01

    Classical galactosemia (G/G) is caused by the absence of galactose-1-phosphate uridyl transferase (GALT) activity while the Duarte allele produces partial impairment and a specific biochemical phenotype. Cloning and sequencing of the human GALT gene has enabled the identification of prevalent mutations for both Classical and Duarte alleles. The G allele is caused by a Q188R codon mutation in exon 6 in 70% of a Caucasian population while the D allele is caused by an N134D codon mutation in exon 10. Since the Q188R sequence creates a new Hpa II site and the N314D sequence creates a new Sin I site, it is relatively easy to screen for both mutations by multiplex PCR and restriction digest. Here we describe a method for detection of new mutations producing impaired GALT. Patient DNAs are subjected to SSCP (single strand conformational polymorphism) analysis of their 11 GALT exons. Direct sequencing of the exons targeted by SSCP has revealed many codon changes: IVSC 956 (a splice acceptor site loss), S135L, V151A, E203K, A320T, and Y323D. Two of these codon changes, V151A and S135L, have been confirmed as mutations by finding impaired GALT activity in a yeast expression system. We conclude that molecular screening of GALT DNA will clarify the structural biology of GALT and the pathophysiology of galactosemia.

  3. Analysis of Transcriptional Signatures in Response to Listeria monocytogenes Infection Reveals Temporal Changes That Result from Type I Interferon Signaling

    Science.gov (United States)

    Potempa, Krzysztof; Graham, Christine M.; Moreira-Teixeira, Lucia; McNab, Finlay W.; Howes, Ashleigh; Stavropoulos, Evangelos; Pascual, Virginia; Banchereau, Jacques; Chaussabel, Damien; O’Garra, Anne

    2016-01-01

    Analysis of the mouse transcriptional response to Listeria monocytogenes infection reveals that a large set of genes are perturbed in both blood and tissue and that these transcriptional responses are enriched for pathways of the immune response. Further we identified enrichment for both type I and type II interferon (IFN) signaling molecules in the blood and tissues upon infection. Since type I IFN signaling has been reported widely to impair bacterial clearance we examined gene expression from blood and tissues of wild type (WT) and type I IFNαβ receptor-deficient (Ifnar1-/-) mice at the basal level and upon infection with L. monocytogenes. Measurement of the fold change response upon infection in the absence of type I IFN signaling demonstrated an upregulation of specific genes at day 1 post infection. A less marked reduction of the global gene expression signature in blood or tissues from infected Ifnar1-/- as compared to WT mice was observed at days 2 and 3 after infection, with marked reduction in key genes such as Oasg1 and Stat2. Moreover, on in depth analysis, changes in gene expression in uninfected mice of key IFN regulatory genes including Irf9, Irf7, Stat1 and others were identified, and although induced by an equivalent degree upon infection this resulted in significantly lower final gene expression levels upon infection of Ifnar1-/- mice. These data highlight how dysregulation of this network in the steady state and temporally upon infection may determine the outcome of this bacterial infection and how basal levels of type I IFN-inducible genes may perturb an optimal host immune response to control intracellular bacterial infections such as L. monocytogenes. PMID:26918359

  4. Screening for psychosocial problems in children attending the pediatric clinic at king Khalid university hospital (KKUH in Riyadh (KSA

    Directory of Open Access Journals (Sweden)

    Ibrahim H Al-Ayed

    2008-01-01

    Conclusion: This study revealed the feasibility of screening for behavioral problems of children in an outpatient setting. It is necessary to implement screening procedures for psycho-behavioral problems, and train pediatricians to screen children presenting at clinics.

  5. Mammography screening services: market segments and messages.

    Science.gov (United States)

    Scammon, D L; Smith, J A; Beard, T

    1991-01-01

    Mammography has become a vital tool for the early detection of breast cancer. Although many organizations and health care facilities are working to educate and motivate women to take advantage of the life saving opportunity that is offered through screening mammography, only twenty percent of women who should be screened actually have the procedure performed. In order to reach women who have not been screened, it is important to learn which factors most strongly motivate those women who do choose to have a mammogram. Depth interviews with 18 women attending a mobile mammography unit were conducted to explore the decision making process of women obtaining mammography screening services and to develop a profile of prevalent emotions, attitudes, and feelings associated with receiving breast cancer screening services. Analysis of the interview transcripts revealed several important themes to which health care professionals can direct marketing and health promotion strategies.

  6. Screening for Glaucoma

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Glaucoma The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Glaucoma . This final recommendation statement ...

  7. Liver (Hepatocellular) Cancer Screening

    Science.gov (United States)

    ... Treatment Liver Cancer Prevention Liver Cancer Screening Research Liver (Hepatocellular) Cancer Screening (PDQ®)–Patient Version What is ... These are called diagnostic tests . General Information About Liver (Hepatocellular) Cancer Key Points Liver cancer is a ...

  8. Hearing Loss: Screening Newborns

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Hearing Loss Screening Newborns Past Issues / Spring 2015 Table ... deafness, which account for most cases. Screening Newborns' Hearing Now Standard In 1993, children born in the ...

  9. Cervical Cancer Screening

    Science.gov (United States)

    ... Cancer found early may be easier to treat. Cervical cancer screening is usually part of a woman's health ... may do more tests, such as a biopsy. Cervical cancer screening has risks. The results can sometimes be ...

  10. Screening for Cervical Cancer

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Cervical Cancer The U.S. Preventive Services Task Force (Task Force) has issued final recommendations on Screening for Cervical Cancer . These recommendations are for women ...

  11. Molecular Dynamics Simulations Reveal the Conformational Flexibility of Lipid II and Its Loose Association with the Defensin Plectasin in the Staphylococcus aureus Membrane

    DEFF Research Database (Denmark)

    Witzke, Sarah; Petersen, Michael; Carpenter, Timothy S.

    2016-01-01

    dynamics simulation study of the conformational dynamics of Lipid II within a detailed model of the Staphylococcus aureus cell membrane. We show that Lipid II is able to adopt a range of conformations, even within the packed lipidic environment of the membrane. Our simulations also reveal dimerization...... the biosynthesis of the cell wall. Given the urgent need for development of novel antibiotics to counter the growing threat of bacterial infection resistance, it is imperative that a thorough molecular-level characterization of the molecules targeted by antibiotics be achieved. To this end, we present a molecular...... of Lipid II mediated by cations. In the presence of the defensin peptide plectasin, the conformational lability of Lipid II allows it to form loose complexes with the protein, via a number of different binding modes....

  12. Between Stage and Screen

    NARCIS (Netherlands)

    Tornqvist, Egil

    1996-01-01

    Ingmar Bergman is worldwide known as a film and stage director. Yet no-one has attempted to compare his stage and screen activities. In Between stage and screen Egil Tornqvist examines formal and thematical correspondences and differences between a number of Bergman's stage, screen, and radio

  13. Inexpensive and fast pathogenic bacteria screening using field-effect transistors.

    Science.gov (United States)

    Formisano, Nello; Bhalla, Nikhil; Heeran, Mel; Reyes Martinez, Juana; Sarkar, Amrita; Laabei, Maisem; Jolly, Pawan; Bowen, Chris R; Taylor, John T; Flitsch, Sabine; Estrela, Pedro

    2016-11-15

    While pathogenic bacteria contribute to a large number of globally important diseases and infections, current clinical diagnosis is based on processes that often involve culturing which can be time-consuming. Therefore, innovative, simple, rapid and low-cost solutions to effectively reduce the burden of bacterial infections are urgently needed. Here we demonstrate a label-free sensor for fast bacterial detection based on metal-oxide-semiconductor field-effect transistors (MOSFETs). The electric charge of bacteria binding to the glycosylated gates of a MOSFET enables quantification in a straightforward manner. We show that the limit of quantitation is 1.9×10(5) CFU/mL with this simple device, which is more than 10,000-times lower than is achieved with electrochemical impedance spectroscopy (EIS) and matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-ToF) on the same modified surfaces. Moreover, the measurements are extremely fast and the sensor can be mass produced at trivial cost as a tool for initial screening of pathogens. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. A Simple Assay to Screen Antimicrobial Compounds Potentiating the Activity of Current Antibiotics

    Directory of Open Access Journals (Sweden)

    Junaid Iqbal

    2013-01-01

    Full Text Available Antibiotic resistance continues to pose a significant problem in the management of bacterial infections, despite advances in antimicrobial chemotherapy and supportive care. Here, we suggest a simple, inexpensive, and easy-to-perform assay to screen antimicrobial compounds from natural products or synthetic chemical libraries for their potential to work in tandem with the available antibiotics against multiple drug-resistant bacteria. The aqueous extract of Juglans regia tree bark was tested against representative multiple drug-resistant bacteria in the aforementioned assay to determine whether it potentiates the activity of selected antibiotics. The aqueous extract of J. regia bark was added to Mueller-Hinton agar, followed by a lawn of multiple drug-resistant bacteria, Salmonella typhi or enteropathogenic E. coli. Next, filter paper discs impregnated with different classes of antibiotics were placed on the agar surface. Bacteria incubated with extract or antibiotics alone were used as controls. The results showed a significant increase (>30% in the zone of inhibition around the aztreonam, cefuroxime, and ampicillin discs compared with bacteria incubated with the antibiotics/extract alone. In conclusion, our assay is able to detect either synergistic or additive action of J. regia extract against multiple drug-resistant bacteria when tested with a range of antibiotics.

  15. Inhibiting AMPylation: a novel screen to identify the first small molecule inhibitors of protein AMPylation.

    Science.gov (United States)

    Lewallen, Daniel M; Sreelatha, Anju; Dharmarajan, Venkatasubramanian; Madoux, Franck; Chase, Peter; Griffin, Patrick R; Orth, Kim; Hodder, Peter; Thompson, Paul R

    2014-02-21

    Enzymatic transfer of the AMP portion of ATP to substrate proteins has recently been described as an essential mechanism of bacterial infection for several pathogens. The first AMPylator to be discovered, VopS from Vibrio parahemolyticus, catalyzes the transfer of AMP onto the host GTPases Cdc42 and Rac1. Modification of these proteins disrupts downstream signaling events, contributing to cell rounding and apoptosis, and recent studies have suggested that blocking AMPylation may be an effective route to stop infection. To date, however, no small molecule inhibitors have been discovered for any of the AMPylators. Therefore, we developed a fluorescence-polarization-based high-throughput screening assay and used it to discover the first inhibitors of protein AMPylation. Herein we report the discovery of the first small molecule VopS inhibitors (e.g., calmidazolium, GW7647, and MK886) with Ki's ranging from 6 to 50 μM and upward of 30-fold selectivity versus HYPE, the only known human AMPylator.

  16. Screening for colorectal cancer.

    Science.gov (United States)

    He, Jin; Efron, Jonathan E

    2011-01-01

    March is national colorectal cancer awareness month. It is estimated that as many as 60% of colorectal cancer deaths could be prevented if all men and women aged 50 years or older were screened routinely. In 2000, Katie Couric's televised colonoscopy led to a 20% increase in screening colonoscopies across America, a stunning rise called the "Katie Couric Effect". This event demonstrated how celebrity endorsement affects health behavior. Currently, discussion is ongoing about the optimal strategy for CRC screening, particularly the costs of screening colonoscopy. The current CRC screening guidelines are summarized in Table 2. Debates over the optimum CRC screening test continue in the face of evidence that 22 million Americans aged 50 to 75 years are not screened for CRC by any modality and 25,000 of those lives may have been saved if they had been screened for CRC. It is clear that improving screening rates and reducing disparities in underscreened communities and population subgroups could further reduce colorectal cancer morbidity and mortality. National Institutes of Health consensus identified the following priority areas to enhance the use and quality of colorectal cancer screening: Eliminate financial barriers to colorectal cancer screening and appropriate follow-up of positive results of colorectal cancer screening. Develop systems to ensure the high quality of colorectal cancer screening programs. Conduct studies to determine the comparative effectiveness of the various colorectal cancer screening methods in usual practice settings. Encouraging population adherence to screening tests and allowing patients to select the tests they prefer may do more good (as long as they choose something) than whatever procedure is chosen by the medical profession as the preferred test.

  17. Cost-effectiveness of breast cancer screening policies using simulation.

    Science.gov (United States)

    Gocgun, Y; Banjevic, D; Taghipour, S; Montgomery, N; Harvey, B J; Jardine, A K S; Miller, A B

    2015-08-01

    In this paper, we study breast cancer screening policies using computer simulation. We developed a multi-state Markov model for breast cancer progression, considering both the screening and treatment stages of breast cancer. The parameters of our model were estimated through data from the Canadian National Breast Cancer Screening Study as well as data in the relevant literature. Using computer simulation, we evaluated various screening policies to study the impact of mammography screening for age-based subpopulations in Canada. We also performed sensitivity analysis to examine the impact of certain parameters on number of deaths and total costs. The analysis comparing screening policies reveals that a policy in which women belonging to the 40-49 age group are not screened, whereas those belonging to the 50-59 and 60-69 age groups are screened once every 5 years, outperforms others with respect to cost per life saved. Our analysis also indicates that increasing the screening frequencies for the 50-59 and 60-69 age groups decrease mortality, and that the average number of deaths generally decreases with an increase in screening frequency. We found that screening annually for all age groups is associated with the highest costs per life saved. Our analysis thus reveals that cost per life saved increases with an increase in screening frequency. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. [Microbiological diagnosis of bacterial infection associated with delivery and postpartum].

    Science.gov (United States)

    Padilla-Ortega, Belén; Delgado-Palacio, Susana; García-Garrote, Fernando; Rodríguez-Gómez, Juan Miguel; Romero-Hernández, Beatriz

    2016-05-01

    The newborn may acquire infections during delivery due to maternal colonization of the birth canal, by microorganisms such as Streptococcus agalactiae that caused early neonatal infection, or acquisition through the placenta, amniotic fluid or birth products. After birth, the newborn that needs hospitalization can develop nosocomial infections during their care and exceptionally through lactation by infectious mastitis or incorrect handling of human milk, which does not require to stop breastfeeding in most cases. It is important and necessary to perform microbiological diagnosis for the correct treatment of perinatal infections, especially relevant in preterm infants with low or very low weight with high mortality rates. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  19. Bacterial infections in alcoholic and nonalcoholic liver cirrhosis

    DEFF Research Database (Denmark)

    Sargenti, Konstantina; Prytz, Hanne; Bertilsson, Sara

    2015-01-01

    .001), this relationship was not significant after adjustment for confounders in Cox regression analysis (P=0.056). Resistance to piperacilin-tazobactam and carbapenems was more common in infections occurring in alcoholic versus nonalcoholic cirrhosis (13 vs. 5%, P=0.057 and 12 vs. 2%, P=0.009). Alcoholic etiology...

  20. Serious bacterial infections in febrile young children: Lack of value ...

    African Journals Online (AJOL)

    Young children often attend primary care institutions and emergency departments with ... Three-quarters (~1 000) are admitted for subspecialist care and tend to be afebrile on ..... occurred after the first 3 days of hospitalisation, with the median time to death .... are extremely useful markers to aid in diagnosis, whereas there.

  1. Healthcare-associated viral and bacterial infections in dentistry

    NARCIS (Netherlands)

    Laheij, A.M.G.A.; Kistler, J.O.; Belibasakis, G.N.; Valimaa, H.; de Soet, J.J.

    2012-01-01

    Infection prevention in dentistry is an important topic that has gained more interest in recent years and guidelines for the prevention of cross-transmission are common practice in many countries. However, little is known about the real risks of cross-transmission, specifically in the dental

  2. Hypovitaminosis A coupled to secondary bacterial infection in beef cattle

    Directory of Open Access Journals (Sweden)

    He Xiuyuan

    2012-11-01

    Full Text Available Abstract Background Vitamin A is essential for normal growth, development, reproduction, cell proliferation, cell differentiation, immune function and vision. Hypovitaminosis A can lead to a series of pathological damage in animals. This report describes the case of hypovitaminosis A associated with secondary complications in calves. Case presentation From February to March in 2011, 2-and 3-month old beef calves presented with decreased eyesight, apparent blindness and persistent diarrhea occurred in a cattle farm of Hubei province, China. Based on history inspection and clinical observation, we made a tentative diagnosis of hypovitaminosis A. The disease was confirmed as a congenital vitamin A deficiency by determination of the concentrations of vitamin A in serum and feed samples. Furthermore, pathological and microbiological examination showed that the disease was associated with pathogenic Escherichia coli (E. coli infection and mucosal barriers damage in intestines. The corresponding treatments were taken immediately, and the disease was finally under control for a month. Conclusions To our knowledge, this is the first report of hypovitaminosis A coupled to secondary infection of E. coli in beef cattle, advancing our knowledge of how vitamin A affects infection and immunity in animals. This study could also be contributed to scientific diagnosis and treatments of complex hypovitaminosis A in cattle.

  3. Advances in nucleic acid-based diagnostics of bacterial infections

    DEFF Research Database (Denmark)

    Barken, Kim Bundvig; Haagensen, Janus Anders Juul; Tolker-Nielsen, Tim

    2007-01-01

    Methods for rapid detection of infectious bacteria and antimicrobial-resistant pathogens have evolved significantly over the last decade. Many of the new procedures are nucleic acid-based and replace conventional diagnostic methods like culturing which is time consuming especially with fastidious...... of these pathogens is important to isolate patients and prevent further spreading of the diseases. Newly developed diagnostic procedures are superior with respect to turnaround time, sensitivity and specificity. Methods like multiplex real time PCR and different array-based technologies offer the possibility...

  4. STUDIES ON BACTERIAL INFECTIONS OF DIABETIC FOOT ULCER

    African Journals Online (AJOL)

    Dr Oboro VO

    Microbial study for aerobic organisms from 100 cases of diabetic foot ulcers was carried out to determine the ... affect 239 million people world wide. ... cause the breakdown of the skin. ... complications, such as peripheral vascular disease,.

  5. Bacterial Infection Increases Reproductive Investment in Burying Beetles

    Directory of Open Access Journals (Sweden)

    Catherine E. Reavey

    2015-10-01

    Full Text Available The Nicrophorus genus lives and breeds in a microbe rich environment. As such, it would be expected that strategies should be in place to counter potentially negative effects of the microbes common to this environment. In this study, we show the response of Nicrophorus vespilloides to the common soil bacterium, Bacillus subtilis. Phenoloxidase (PO levels are not upregulated in response to the challenge and the bacteria are observed to multiply within the haemolymph of the host. Despite the growth of B. subtilis, survival is not affected, either in virgin or in breeding beetles. Some limit on bacterial growth in the haemolymph does seem to be occurring, suggesting mechanisms of resistance, in addition to tolerance mechanisms. Despite limited detrimental effects on the individual, the challenge by Bacillus subtilis appears to act as a cue to increase reproductive investment. The challenge may indicate a suite of negative environmental conditions that could compromise future breeding opportunities. This could act as a cue to increase parental investment in the current bout.

  6. Novel approaches to developing new antibiotics for bacterial infections

    OpenAIRE

    Coates, A R M; Hu, Y

    2007-01-01

    Antibiotics are an essential part of modern medicine. The emergence of antibiotic-resistant mutants among bacteria is seemingly inevitable, and results, within a few decades, in decreased efficacy and withdrawal of the antibiotic from widespread usage. The traditional answer to this problem has been to introduce new antibiotics that kill the resistant mutants. Unfortunately, after more than 50 years of success, the pharmaceutical industry is now producing too few antibiotics, particularly aga...

  7. Emerging infectious diseases with cutaneous manifestations: Viral and bacterial infections.

    Science.gov (United States)

    Nawas, Zeena Y; Tong, Yun; Kollipara, Ramya; Peranteau, Andrew J; Woc-Colburn, Laila; Yan, Albert C; Lupi, Omar; Tyring, Stephen K

    2016-07-01

    Given increased international travel, immigration, and climate change, bacterial and viral infections that were once unrecognized or uncommon are being seen more frequently in the Western Hemisphere. A delay in diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. We review the epidemiology, cutaneous manifestations, diagnosis, and management of these emerging bacterial and viral diseases. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  8. Imaging of bacterial infections of the sacroiliac joint

    International Nuclear Information System (INIS)

    Groves, C.; Cassar-Pullicino, V.

    2004-01-01

    Infection of the sacroiliac joint can be pyogenic or granulomatous and is usually unilateral. There are a number of predisposing conditions including drug abuse and intra articular steroid injection, but in 44% of cases, no definite predisposing factors can be identified. Considerable delay between presentation and diagnosis is recognized. The clinical picture may be non-specific and variable, and clinical suspicion may be low due to the relatively low incidence of the condition. This is compounded by difficulties in clinical examination of the SIJs. The diagnosis is based on a history suggestive of infection, clinical or radiographic localization to the SIJs, and a positive blood culture or joint aspirate. The pathology of pyogenic sacroiliitis is reviewed with respect to the anatomy of the SIJ, and the differential diagnoses considered. The imaging findings, and relative merits of all the modalities are discussed with particular consideration given to changes over the course of the disease. Imaging strategies are evaluated and proposed. As the commonest presenting symptom is low back pain, consideration should be given to the addition of a STIR sequence covering the SIJs on all routine lumbar spine MR examinations. MR imaging is the most sensitive and specific imaging modality, while CT-guided arthrocentesis improves diagnostic confidence. Tc 99 MDP blood pool imaging mirrors the clinical features of resolution, and scintigraphy may be the best method to monitor response to treatment. Targeted antibiotic therapy usually leads to a full recovery. A high incidence of clinical suspicion, with MR imaging at an early stage are the essential prerequisites to an accurate diagnosis of bacterial sacroiliitis. (orig.) [de

  9. Diagnosis of bacterial infection | Boyles | South African Medical ...

    African Journals Online (AJOL)

    Because of slow turnaround times, these tests are frequently used to focus or stop antibiotic therapy after empiric initiation. Nucleic acid amplification tests raise the possibility of detecting organisms with high sensitivity, specificity and reduced turnaround time, and novel diagnostic modalities relying on nanotechnology and ...

  10. Bacterial infection increases risk of carcinogenesis by targeting mitochondria

    DEFF Research Database (Denmark)

    Strickertsson, Jesper A.B.; Desler, Claus; Rasmussen, Lene Juel

    2017-01-01

    pathways, and compares the impact of the bacterial alteration of mitochondrial function to that of cancer. Bacterial virulence factors have been demonstrated to induce mutations of mitochondrial DNA (mtDNA) and to modulate DNA repair pathways of the mitochondria. Furthermore, virulence factors can induce...... or impair the intrinsic apoptotic pathway. The effect of bacterial targeting of mitochondria is analogous to behavior of mitochondria in a wide array of tumours, and this strongly suggests that mitochondrial targeting of bacteria is a risk factor for carcinogenesis....

  11. Surveillance of acute community acquired urinary tract bacterial infections

    Directory of Open Access Journals (Sweden)

    Sibanarayan Rath

    2015-08-01

    Conclusions: It was concluded that periodic surveillance of pathogens is an essential corollary in effective health management in any country, as empiric therapy is a common/essential practice in effective clinical management.

  12. Bacterial Infections Following Splenectomy for Malignant and Nonmalignant Hematologic Diseases

    Science.gov (United States)

    Leone, Giuseppe; Pizzigallo, Eligio

    2015-01-01

    Splenectomy, while often necessary in otherwise healthy patients after major trauma, finds its primary indication for patients with underlying malignant or nonmalignant hematologic diseases. Indications of splenectomy for hematologic diseases have been reducing in the last few years, due to improved diagnostic and therapeutic tools. In high-income countries, there is a clear decrease over calendar time in the incidence of all indication splenectomy except nonmalignant hematologic diseases. However, splenectomy, even if with different modalities including laparoscopic splenectomy and partial splenectomy, continue to be a current surgical practice both in nonmalignant hematologic diseases, such as Immune Thrombocytopenic Purpura (ITP), Autoimmune Hemolytic Anemia (AIHA), Congenital Hemolytic Anemia such as Spherocytosis, Sickle Cell Anemia and Thalassemia and Malignant Hematological Disease, such as lymphoma. Today millions of people in the world are splenectomized. Splenectomy, independently of its cause, induces an early and late increase in the incidence of venous thromboembolism and infections. Infections remain the most dangerous complication of splenectomy. After splenectomy, the levels of antibody are preserved but there is a loss of memory B cells against pneumococcus and tetanus, and the loss of marginal zone monocytes deputed to immunological defense from capsulated bacteria. Commonly, the infections strictly correlated to the absence of the spleen or a decreased or absent splenic function are due to encapsulated bacteria that are the most virulent pathogens in this set of patients. Vaccination with polysaccharide and conjugate vaccines again Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis should be performed before the splenectomy. This practice reduces but does not eliminate the occurrence of overwhelming infections due to capsulated bacteria. At present, most of infections found in splenectomized patients are due to Gram-negative (G-) bacteria. The underlying disease is the most important factor in determining the frequency and severity of infections. So, splenectomy for malignant diseases has the major risk of infections. PMID:26543526

  13. Impact of bacterial infections on aging and cancer

    DEFF Research Database (Denmark)

    Strickertsson, Jesper A B; Madsen, Claus Desler; Rasmussen, Lene Juel

    2014-01-01

    DNA repair subunits of major DNA repair pathways and increase production of reactive oxygen species (ROS). Defects in DNA repair cause mutations and genomic instability and are found in several cancers as well as in progeroid syndromes. This review describes our contemporary view on how bacterial...

  14. Serious bacterial infections in febrile young children: Lack of value ...

    African Journals Online (AJOL)

    avoidance of unnecessary antibiotic use should also be considered important in this time of emerging ... In addition, the avoidance of unnecessary antibiotics is important in this time of emerging ..... conjugate vaccine era. Acad Emerg Med ...

  15. Bacterial infections in Lilongwe, Malawi: aetiology and antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Makoka Mwai H

    2012-03-01

    Full Text Available Abstract Background Life-threatening infections present major challenges for health systems in Malawi and the developing world because routine microbiologic culture and sensitivity testing are not performed due to lack of capacity. Use of empirical antimicrobial therapy without regular microbiologic surveillance is unable to provide adequate treatment in the face of emerging antimicrobial resistance. This study was conducted to determine antimicrobial susceptibility patterns in order to inform treatment choices and generate hospital-wide baseline data. Methods Culture and susceptibility testing was performed on various specimens from patients presenting with possible infectious diseases at Kamuzu Central Hospital, Lilongwe, Malawi. Results Between July 2006 and December 2007 3104 specimens from 2458 patients were evaluated, with 60.1% from the adult medical service. Common presentations were sepsis, meningitis, pneumonia and abscess. An etiologic agent was detected in 13% of patients. The most common organisms detected from blood cultures were Staphylococcus aureus, Escherichia coli, Salmonella species and Streptococcus pneumoniae, whereas Streptococcus pneumoniae and Cryptococcus neoformans were most frequently detected from cerebrospinal fluid. Haemophilus influenzae was rarely isolated. Resistance to commonly used antibiotics was observed in up to 80% of the isolates while antibiotics that were not commonly in use maintained susceptibility. Conclusions There is widespread resistance to almost all of the antibiotics that are empirically used in Malawi. Antibiotics that have not been widely introduced in Malawi show better laboratory performance. Choices for empirical therapy in Malawi should be revised accordingly. A microbiologic surveillance system should be established and prudent use of antimicrobials promoted to improve patient care.

  16. Fluorescence targeted imaging of cancer and bacterial infections

    NARCIS (Netherlands)

    Oosten, Marleen van

    2014-01-01

    In de chirurgie worden verschillende beeldvormingstechnieken gebruikt, zowel voor diagnostiek rondom een operatie, als begeleidende beeldvorming tijdens een operatie. Voorbeelden van veelgebruikte beeldvormingstechnieken in de kliniek zijn standaard röntgendiagnostiek, computed tomography (CT),

  17. Bacterial infection of the lower respiratory tract in 34 horses.

    Science.gov (United States)

    Racklyeft, D J; Love, D N

    2000-08-01

    To investigate associations between the bacteriology and aspects of history, clinical presentation, outcome and pathology of lower respiratory tract disease of 34 horses. Detailed aerobic and anaerobic bacteriological investigations were performed on clinical specimens from horses with pneumonia, lung abscessation and necrotic pneumonia with or without pleurisy in an attempt to identify those bacteria that might contribute to the initiation and progression of infection. Bacteria were cultured from 33 of the 34 horses. In ten cases, only aerobic/facultatively anaerobic isolates were cultured while aerobic/facultatively anaerobic bacteria and obligately anaerobic bacteria were isolated in the other 23 cases. Moderate to large numbers of anaerobic bacteria were isolated only when the estimated duration of illness was at least five days. Bacteria were not cultured from 12 of the pleural fluid samples but were always cultured from pulmonary samples (either transtracheal aspirates from live horses or pulmonary lesions at necropsy). Streptococcus equi subsp zooepidemicus was isolated in the three cases where only one bacterial species was cultured. In the other 30 cases, multiple species were isolated. These included most often and in greatest numbers, Streptococcus equi subsp zooepidemicus, Pasteurellaceae, Escherichia coli, anaerobic cocci, Eubacterium fossor, Bacteroides tectum, Prevotella heparinolytica, Fusobacterium spp, and pigmented members of the genera Prevotella and Porphyromonas. Aerobic/facultatively anaerobic organisms were isolated from 97% of horses, while obligately anaerobic organisms were cultured from 68% of horses. There was no association between the isolation of any specific bacterium and the outcome of disease. However, obligately anaerobic bacteria (such as anaerobic cocci, Bacteroides tectum, P heparinolytica and Fusobacterium spp) and the facultatively anaerobic species Escherichia coli, were recovered more commonly from horses that died or were euthanased than from those that survived. There was an association between failure of horses to recover from pleuropneumonia and delay in diagnosis and initiation of treatment.

  18. Serious bacterial infections in febrile young children: Lack of value ...

    African Journals Online (AJOL)

    Fever is both a marker of insignificant viral infection, as well as more serious bacterial sepsis. Therefore ... febrile children under the age of 5 years (with an axillary temperature ≥38°C) who presented to Steve Biko Academic Hospital, Pretoria, with signs and symptoms of pneumonia, meningitis and/or generalised sepsis.

  19. Studies on bacterial infections of diabetic foot ulcer | Hena | African ...

    African Journals Online (AJOL)

    African Journal of Clinical and Experimental Microbiology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 11, No 3 (2010) >. Log in or Register to get access to full text downloads.

  20. Screen Practice in Curating

    DEFF Research Database (Denmark)

    Toft, Tanya Søndergaard

    2014-01-01

    During the past one and a half decade, a curatorial orientation towards "screen practice" has expanded the moving image and digital art into the public domain, exploring alternative artistic uses of the screen. The emergence of urban LED screens in the late 1990s provided a new venue that allowed...... for digital art to expand into public space. It also offered a political point of departure, inviting for confrontation with the Spectacle and with the politics and ideology of the screen as a mass communication medium that instrumentalized spectator positions. In this article I propose that screen practice...... to the dispositif of screen practice in curating, resulting in a medium-based curatorial discourse. With reference to the nomadic exhibition project Nordic Outbreak that I co-curated with Nina Colosi in 2013 and 2014, I suggest that the topos of the defined visual display area, frequently still known as "the screen...

  1. Pain during mammography: Implications for breast screening programmes

    International Nuclear Information System (INIS)

    Andrews, F.J.

    2001-01-01

    Pain experienced during mammography can deter women from attending for breast cancer screening. Review of the current literature on pain experienced during mammography reveals three main areas of interest: reports of the frequency of pain, identification of predictors of pain and strategies for responding to pain. Implications of this literature for breast screening programmes include the need for appropriate measurements of pain during mammography that are valid for screening populations, a further understanding of organizational factors involved in screening programmes that may be predictors of pain and for the development of valid strategies for responding to pain within breast screening programmes. Copyright (2001) Blackwell Science Pty Ltd

  2. Automated Groundwater Screening

    International Nuclear Information System (INIS)

    Taylor, Glenn A.; Collard, Leonard B.

    2005-01-01

    The Automated Intruder Analysis has been extended to include an Automated Ground Water Screening option. This option screens 825 radionuclides while rigorously applying the National Council on Radiation Protection (NCRP) methodology. An extension to that methodology is presented to give a more realistic screening factor for those radionuclides which have significant daughters. The extension has the promise of reducing the number of radionuclides which must be tracked by the customer. By combining the Automated Intruder Analysis with the Automated Groundwater Screening a consistent set of assumptions and databases is used. A method is proposed to eliminate trigger values by performing rigorous calculation of the screening factor thereby reducing the number of radionuclides sent to further analysis. Using the same problem definitions as in previous groundwater screenings, the automated groundwater screening found one additional nuclide, Ge-68, which failed the screening. It also found that 18 of the 57 radionuclides contained in NCRP Table 3.1 failed the screening. This report describes the automated groundwater screening computer application

  3. Screening for abdominalt aortaaneurisme

    DEFF Research Database (Denmark)

    Lindholt, J S; Juul, Svend; Henneberg, E W

    1997-01-01

    rupture. Ultrasonographic screening for AAA takes 10 minutes per scan, and the sensitivity and specificity are high. Ultrasonographic screening for AAA is a reliable, safe and inexpensive method for screening, and screening for AAA is discussed worldwide. One point four percent of deaths among men from 65...... to 80 year of age are caused by ruptured AAA. Screening men over 65 for AAA can theoretically prevent a substantial number of deaths. Our calculations predict one prevented AAA-death per 200-300 scans for a cost of about 4000 DKK per saved year of life. However, cost-benefit analyses are based...... on uncertain assumptions concerning prevalence, incidence and risk of rupture. Therefore a randomized trial screening of 65-73 year old males is taking place in the County of Viborg in Denmark. Udgivelsesdato: 1997-Mar-24...

  4. Cathode ray tube screens

    International Nuclear Information System (INIS)

    Cockayne, B.; Robbins, D.J.; Glasper, J.L.

    1982-01-01

    An improved cathode ray tube screen is described which consists of a single- or a poly-crystalline slice of a material such as yttrium aluminium garnet in which dopants such as Tb 3 + , Eu 3 + , Ce 3 + or Tm 3 + are ion implanted to different depths or in different areas of the screen. Annealing the screen removes lattice damage caused by the ion implanting and assists the diffusion of the dopant into the crystal. (U.K.)

  5. Colorectal Cancer Screening

    OpenAIRE

    Quintero, Enrique; Saito, Yutaka; Hassan, Cessare; Senore, Carlo

    2012-01-01

    Colorectal cancer, which is the leading cancer in Singapore, can be prevented by increased use of screening and polypectomy. A range of screening strategies such as stool-based tests, flexible sigmoidoscopy, colonoscopy and computed tomography colonography are available, each with different strengths and limitations. Primary care physicians should discuss appropriate screening modalities with their patients, tailored to their individual needs. Physicians, patients and the government should wo...

  6. Colorectal cancer screening

    OpenAIRE

    Plumb, A. A.; Halligan, S.

    2015-01-01

    Colorectal cancer is a major public health burden worldwide. There is clear-cut evidence that screening will reduce colorectal cancer mortality and the only contentious issue is which screening tool to use. Most evidence points towards screening with fecal occult blood testing. The immunochemical fecal occult blood tests have a higher sensitivity than the guaiac-based tests. In addition, their automation and haemoglobin quantification allows a threshold for colonoscopy to be selected that can...

  7. In-bead screening

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to screening of one-bead-one-compound (OBOC) combinatorial libraries which is useful for the discovery of compounds displaying molecular interactions with a biological or a physicochemical system, such as substrates and inhibitors of enzymes and the like. The invention...... provides a method for screening a library of compounds for their interaction with a physico- chemical or biological system and a corresponding kit for performing the method of screening a one-bead-one-compound library of compounds....

  8. Early Detection of Autism (ASD) by a Non-invasive Quick Measurement of Markedly Reduced Acetylcholine & DHEA and Increased β-Amyloid (1-42), Asbestos (Chrysotile), Titanium Dioxide, Al, Hg & often Coexisting Virus Infections (CMV, HPV 16 and 18), Bacterial Infections etc. in the Brain and Corresponding Safe Individualized Effective Treatment.

    Science.gov (United States)

    Omura, Yoshiaki; Lu, Dominic; Jones, Marilyn K; Nihrane, Ahdallah; Duvvi, Harsha; Shimotsuura, Yasuhiro; Ohki, Motomu

    2015-01-01

    A brief historical background on Autism & some of the important symptoms associated with Autism are summarized. Using strong Electro Magnetic Field Resonance Phenomenon between 2 identical molecules with identical weight (which received U.S. Patent) non-invasively & rapidly we can detect various molecules including neurotransmitters, bacteria, virus, fungus, metals & abnormal molecules. Simple non- invasive measurement of various molecules through pupils & head of diagnosed or suspected Autism patients indicated that in Autism patients following changes were often found: 1) Acetylcholine is markedly reduced; 2) Alzheimer's disease markers (i.e. β-Amyloid (1-42), Tau Protein, Apolipoprotein (Apo E4)) are markedly increased; 3) Chrysotile Asbestos is increased; 4) Titanium Dioxide (TiO2) is moderately increased; 5) Al is moderately increased; 6) Hg is moderately increased; 7) Dopamine, Serotonin & GABA are significantly reduced (up to about 1/10 of normal); 8) Often viral infections (such as CMV, HHV-6, HPV-16, HPV-18, etc.), and Bacterial infections (such as Chlamydia trachomatis, Mycobacterium TB, Borrelia Burgdorferi, etc.) coexist. Research by others on Autism spectrum disorder (ASD) shows that it is a group of complex neurodevelopmental disorders, with about 70% of ASD patients also suffering from gastro-intestinal problems. While Alzheimer disease (AD) is characterized by formation of 1) Amyloid plaques, 2) Neurofibrillary tangles inside of neurons, and 3) Loss of connections between neurons. More than 90% of AD develops in people over the age of 65. These 3 characteristics often progressively worsen over time. Although Autism Spectrum Disorder and Alzheimer's disease are completely different diseases they have some similar biochemical changes. Eight examples of such measurement & analysis are shown for comparison. Most of Autism patients improved significantly by removing the source or preventing intake of Asbestos, TiO2, Al & Hg or enhancing urinary output

  9. Screening Sex: revelando e dissimulando o sexo Screening Sex

    Directory of Open Access Journals (Sweden)

    Linda Williams

    2012-06-01

    Full Text Available Neste texto, procura-se contar a história da exibição do sexo em filmes majoritariamente produzidos nos Estados Unidos no período de quase um século. Ao se perguntar quando, porque e como os Estados Unidos se transformaram de uma cultura que não exibia o sexo em uma que o exibe, a autora insiste no duplo significado do verbo screen (tanto como uma revelação quanto uma dissimulação. Exibir é revelar em uma tela. Mas um segundo e igualmente importante significado, como diz o dicionário é "proteger ou esconder atrás de uma tela". Os filmes tanto revelam como escondem. O artigo analisa a forma como mudanças sociais ocorridas nos Estados Unidos, como, por exemplo, a Revolução sexual dos anos 60 e novas visões a respeito da sexualidade, possibilitaram novas maneiras de representação do sexo no cinema, reorganizando a relação entre o público e o privado. O artigo se pergunta também sobre como nossos corpos e sentidos reagem ao encontro com o sexo na tela, introduzindo a ideia de "saber carnal" (carnal knowledge.In this paper, we try to tell the history of the exhibition of sex in movies mainly produced in the United States in almost a century. Asking when, why and how the United States became - from a culture that did not exhibit sex - into a culture that exhibits it, the author insists in the double sense of the verb to screen (as both a revelation and a dissimulation. To exhibit is to reveal in a screen. But another, and important, sense, as says the dictionary, is "to protect or hide behind a screen". Movies show as well as they reveal. The paper analyzes the way social change in the United States, for example the sexual revolution of the sixties and new views on sexuality allowed new ways of representing sex in the movies, creating a new relation between public and private. The paper also asks how our bodies and senses react to sex in the screen, introducing the idea of "carnal knowledge".

  10. Screening for colorectal cancer

    DEFF Research Database (Denmark)

    Nielsen, Hans J.; Jakobsen, Karen V.; Christensen, Ib J.

    2011-01-01

    Emerging results indicate that screening improves survival of patients with colorectal cancer. Therefore, screening programs are already implemented or are being considered for implementation in Asia, Europe and North America. At present, a great variety of screening methods are available including...... into improvements of screening for colorectal cancer includes blood-based biological markers, such as proteins, DNA and RNA in combination with various demographically and clinically parameters into a "risk assessment evaluation" (RAE) test. It is assumed that such a test may lead to higher acceptance among...... procedures for colorectal cancer. Therefore, results of present research, validating RAE tests, are awaited with interest....

  11. [Overdiagnosis in cancer screening].

    Science.gov (United States)

    Cervera Deval, J; Sentís Crivillé, M; Zulueta, J J

    2015-01-01

    In screening programs, overdiagnosis is defined as the detection of a disease that would have gone undetected without screening when that disease would not have resulted in morbimortality and was treated unnecessarily. Overdiagnosis is a bias inherent in screening and an undesired effect of secondary prevention and improved sensitivity of diagnostic techniques. It is difficult to discriminate a priori between clinically relevant diagnoses and those in which treatment is unnecessary. To minimize the effects of overdiagnosis, screening should be done in patients at risk. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  12. Cancer screening guidelines.

    Science.gov (United States)

    Zoorob, R; Anderson, R; Cefalu, C; Sidani, M

    2001-03-15

    Numerous medical organizations have developed cancer screening guidelines. Faced with the broad, and sometimes conflicting, range of recommendations for cancer screening, family physicians must determine the most reasonable and up-to-date method of screening. Major medical organizations have generally achieved consensus on screening guidelines for breast, cervical and colorectal cancer. For breast cancer screening in women ages 50 to 70, clinical breast examination and mammography are generally recommended every one or two years, depending on the medical organization. For cervical cancer screening, most organizations recommend a Papanicolaou test and pelvic examination at least every three years in patients between 20 and 65 years of age. Annual fecal occult blood testing along with flexible sigmoidoscopy at five-year to 10-year intervals is the standard recommendation for colorectal cancer screening in patients older than 50 years. Screening for prostate cancer remains a matter of debate. Some organizations recommend digital rectal examination and a serum prostate-specific antigen test for men older than 50 years, while others do not. In the absence of compelling evidence to indicate a high risk of endometrial cancer, lung cancer, oral cancer and ovarian cancer, almost no medical organizations have developed cancer screening guidelines for these types of cancer.

  13. Obesity Prevention and Screening.

    Science.gov (United States)

    Mackey, Eleanor R; Olson, Alexandra; DiFazio, Marc; Cassidy, Omni

    2016-03-01

    Obesity is widespread, associated with several physical and psychosocial comorbidities, and is difficult to treat. Prevention of obesity across the lifespan is critical to improving the health of individuals and society. Screening and prevention efforts in primary care are an important step in addressing the obesity epidemic. Each period of human development is associated with unique risks, challenges, and opportunities for prevention and intervention. Screening tools for overweight/obesity, although imperfect, are quick and easy to administer. Screening should be conducted at every primary care visit and tracked longitudinally. Screening tools and cutoffs for overweight and obesity vary by age group. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. ScreenOS Cookbook

    CERN Document Server

    Brunner, Stefan; Delcourt, David

    2008-01-01

    In the only book that completely covers ScreenOS, six key members of Juniper Network's ScreenOS development team help you troubleshoot secure networks using ScreenOS firewall appliances. Over 200 recipes address a wide range of security issues, provide step-by-step solutions, and include discussions of why the recipes work, so you can easily set up and keep ScreenOS systems on track. The easy-to-follow format enables you to find the topic and specific recipe you need right away.

  15. Mammography screening in Denmark

    DEFF Research Database (Denmark)

    Vejborg, Ilse; Mikkelsen, Ellen Margrethe; Garne, Jens Peter

    2011-01-01

    Mammography screening is offered healthy women, and a high standard on professional and organizational level is mandatory not only in the screening programme but even in the diagnostic work-up and treatment. The main goal is to achieve a substantial reduction in disease specific mortality......, but it is not possible to evaluate the effect on mortality until several years later, and continuously monitoring of the quality of all aspects of a screening programme is necessary. Based on other European guidelines, 11 quality indicators have been defined, and guidelines concerning organizational requirements...... for a Danish screening programme as well as recommendations for the radiographic and radiological work have been drawn up....

  16. Epigenetic landscapes reveal transcription factors that regulate CD8+ T cell differentiation.

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P; Pereira, Renata M; Crotty, Shane; Chang, John T; Pipkin, Matthew E; Wang, Wei; Goldrath, Ananda W

    2017-05-01

    Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8 + T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8 + T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8 + T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8 + T cell differentiation.

  17. Epigenetic landscapes reveal transcription factors regulating CD8+ T cell differentiation

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J. Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P.; Pereira, Renata M.; Crotty, Shane; Chang, John T.; Pipkin, Matthew E.; Wang, Wei; Goldrath, Ananda W.

    2017-01-01

    Dynamic changes in the expression of transcription factors (TFs) can influence specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TF among differentially-fated precursor cells suggests additional underlying mechanisms. Here, we profiled genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that TF expression and binding contributed to establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal novel TFs influencing the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector and memory-precursor cell-fates, respectively. Our data define the epigenetic landscape of differentiation intermediates, facilitating identification of TFs with previously unappreciated roles in CD8+ T cell differentiation. PMID:28288100

  18. Cell Wall Remodeling by a Synthetic Analog Reveals Metabolic Adaptation in Vancomycin Resistant Enterococci.

    Science.gov (United States)

    Pidgeon, Sean E; Pires, Marcos M

    2017-07-21

    Drug-resistant bacterial infections threaten to overburden our healthcare system and disrupt modern medicine. A large class of potent antibiotics, including vancomycin, operate by interfering with bacterial cell wall biosynthesis. Vancomycin-resistant enterococci (VRE) evade the blockage of cell wall biosynthesis by altering cell wall precursors, rendering them drug insensitive. Herein, we reveal the phenotypic plasticity and cell wall remodeling of VRE in response to vancomycin in live bacterial cells via a metabolic probe. A synthetic cell wall analog was designed and constructed to monitor cell wall structural alterations. Our results demonstrate that the biosynthetic pathway for vancomycin-resistant precursors can be hijacked by synthetic analogs to track the kinetics of phenotype induction. In addition, we leveraged this probe to interrogate the response of VRE cells to vancomycin analogs and a series of cell wall-targeted antibiotics. Finally, we describe a proof-of-principle strategy to visually inspect drug resistance induction. Based on our findings, we anticipate that our metabolic probe will play an important role in further elucidating the interplay among the enzymes involved in the VRE biosynthetic rewiring.

  19. Distinct Biological Potential of Streptococcus gordonii and Streptococcus sanguinis Revealed by Comparative Genome Analysis.

    Science.gov (United States)

    Zheng, Wenning; Tan, Mui Fern; Old, Lesley A; Paterson, Ian C; Jakubovics, Nicholas S; Choo, Siew Woh

    2017-06-07

    Streptococcus gordonii and Streptococcus sanguinis are pioneer colonizers of dental plaque and important agents of bacterial infective endocarditis (IE). To gain a greater understanding of these two closely related species, we performed comparative analyses on 14 new S. gordonii and 5 S. sanguinis strains using various bioinformatics approaches. We revealed S. gordonii and S. sanguinis harbor open pan-genomes and share generally high sequence homology and number of core genes including virulence genes. However, we observed subtle differences in genomic islands and prophages between the species. Comparative pathogenomics analysis identified S. sanguinis strains have genes encoding IgA proteases, mitogenic factor deoxyribonucleases, nickel/cobalt uptake and cobalamin biosynthesis. On the contrary, genomic islands of S. gordonii strains contain additional copies of comCDE quorum-sensing system components involved in genetic competence. Two distinct polysaccharide locus architectures were identified, one of which was exclusively present in S. gordonii strains. The first evidence of genes encoding the CylA and CylB system by the α-haemolytic S. gordonii is presented. This study provides new insights into the genetic distinctions between S. gordonii and S. sanguinis, which yields understanding of tooth surfaces colonization and contributions to dental plaque formation, as well as their potential roles in the pathogenesis of IE.

  20. Pathogen–host reorganization during Chlamydia invasion revealed by cryo-electron tomography

    Science.gov (United States)

    Nans, Andrea; Saibil, Helen R; Hayward, Richard D

    2014-01-01

    Invasion of host cells is a key early event during bacterial infection, but the underlying pathogen–host interactions are yet to be fully visualized in three-dimensional detail. We have captured snapshots of the early stages of bacterial-mediated endocytosis in situ by exploiting the small size of chlamydial elementary bodies (EBs) for whole-cell cryo-electron tomography. Chlamydiae are obligate intracellular bacteria that infect eukaryotic cells and cause sexually transmitted infections and trachoma, the leading cause of preventable blindness. We demonstrate that Chlamydia trachomatis LGV2 EBs are intrinsically polarized. One pole is characterized by a tubular inner membrane invagination, while the other exhibits asymmetric periplasmic expansion to accommodate an array of type III secretion systems (T3SSs). Strikingly, EBs orient with their T3SS-containing pole facing target cells, enabling the T3SSs to directly contact the cellular plasma membrane. This contact induces enveloping macropinosomes, actin-rich filopodia and phagocytic cups to zipper tightly around the internalizing bacteria. Once encapsulated into tight early vacuoles, EB polarity and the T3SSs are lost. Our findings reveal previously undescribed structural transitions in both pathogen and host during the initial steps of chlamydial invasion. PMID:24809274

  1. Phytochemical Screening, Proximate and Mineral Composition of ...

    African Journals Online (AJOL)

    Leaves of sweet potato (Ipomoea batatas) grown in Tepi area was studied for their class of phytochemicals, mineral and proximate composition using standard analytical methods. The phytochemical screening revealed the presence of alkaloids, flavonoid, terpenoids, saponins, quinones, phenol, tannins, amino acid and ...

  2. International Cancer Screening Network

    Science.gov (United States)

    The International Cancer Screening Network promotes evidence-based cancer screening implementation and evaluation with cooperation from multilateral organizations around the globe. Learn more about how ICSN aims to reduce the global burden of cancer by supporting research and international collaboration.

  3. Touch screens go optical

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner; Jakobsen, Michael Linde; Pedersen, Henrik Chresten

    2012-01-01

    A simple optical implementation of a touch screen is made possible by disrupting the total internal reflection in a 2D waveguide.......A simple optical implementation of a touch screen is made possible by disrupting the total internal reflection in a 2D waveguide....

  4. EIA screening in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Eskild Holm; Christensen, Per; Kørnøv, Lone

    2005-01-01

    The article points out that EIA screening is effectively a regulatory instrument and it can be a cost-effective instrument with environmental benefits.......The article points out that EIA screening is effectively a regulatory instrument and it can be a cost-effective instrument with environmental benefits....

  5. Substance Abuse Screening

    Science.gov (United States)

    ... information is collected, stored or sent over the Internet. To ensure complete privacy, exit your web browser after completing this screening. ... information is collected, stored or sent over the Internet. To ensure complete privacy, exit your web browser after completing this screening. ...

  6. Active versus Passive Screen Time for Young Children

    Science.gov (United States)

    Sweetser, Penelope; Johnson, Daniel; Ozdowska, Anne; Wyeth, Peta

    2012-01-01

    In this paper we report some initial findings from our investigations into the Australian Government's Longitudinal Study of Australian Children dataset. It is revealed that the majority of Australian children are exceeding the government's Screen Time recommendations and that most of their screen time is spent as TV viewing, as opposed to video…

  7. Nasal screening for Staphylococcus aureus--daily routine with improvement potentials.

    Directory of Open Access Journals (Sweden)

    Philipp Warnke

    Full Text Available OBJECTIVES: Staphylococcus aureus causes purulent bacterial infections with a considerable number of life-threatening complications and thus, is a serious cost factor in public health. Up to 50% of a given population could asymptomatically carry Staphylococcus aureus in their nares, thereby serving as a source for contact transmissions and endogenous infections. Nasal swab-based screening techniques are widely used to identify suchcarriers. This study investigated the skill of medical professionals in taking nasal swabs and the effect of teaching on improving bacterial recovery rates. METHODS: 364 persons with different medical educational background participated in this study. A novel anatomically correct artificial nose model was implemented and inoculated with a numerically defined mixture of Staphylococcus aureus and Staphylococcus epidermidis bacteria. Utilizing regular clinical swabs, participants performed screening of the inoculated nose models before and after standardized theoretical, visual, and practical teaching. Recovery of bacteria was measured by standard viable count techniques. Data were analyzed statistically by nonparametric tests. RESULTS: It could be demonstrated that combined theoretical and practical teaching improved bacterial recovery rates. Even experienced medical professionals increased their detection levels after training. Recovery rates of bacteria varied significantly between trained (158.1 CFU and untrained (47.5 CFU participants (Wilcoxon test, p<0.001; Kolmogorov-Smirnov test, p<0.001. CONCLUSIONS: Swabs are commonly used to detect nasal carriage of Staphylococcus aureus in patients. The present teaching algorithm combined with the novel nose model offers an excellent precondition to improve knowledge and performance of this technique. Increased detection rates may prevent from contact transmission due to suboptimum hygienic patient handling. Consecutively, this effect could reduce costs for patient care. This

  8. Oral cancer screening: knowledge is not enough.

    Science.gov (United States)

    Tax, C L; Haslam, S Kim; Brillant, Mgs; Doucette, H J; Cameron, J E; Wade, S E

    2017-08-01

    The purpose of this cross-sectional study was to investigate whether dental hygienists are transferring their knowledge of oral cancer screening into practice. This study also wanted to gain insight into the barriers that might prevent dental hygienists from performing these screenings. A 27-item survey instrument was constructed to study the oral cancer screening practices of licensed dental hygienists in Nova Scotia. A total of 623 practicing dental hygienists received the survey. The response rate was 34% (n = 212) yielding a maximum margin of error of 5.47 at a 95% confidence level. Descriptive statistics were calculated using IBM SPSS Statistics v21 software (Armonk, NY:IBM Corp). Qualitative thematic analysis was performed on any open-ended responses. This study revealed that while dental hygienists perceived themselves as being knowledgeable about oral cancer screening, they were not transferring this knowledge to actual practice. Only a small percentage (13%) of respondents were performing a comprehensive extra-oral examination, and 7% were performing a comprehensive intra-oral examination. The respondents identified several barriers that prevented them from completing a comprehensive oral cancer screening. Early detection of oral cancer reduces mortality rates so there is a professional responsibility to ensure that comprehensive oral cancer screenings are being performed on patients. Dental hygienists may not have the authority in a dental practice to overcome all of the barriers that are preventing them from performing these screenings. Public awareness about oral cancer screenings could increase the demand for screenings and thereby play a role in changing practice norms. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Screen-film mammography

    International Nuclear Information System (INIS)

    Logan, W.W.; Janus, J.A.

    1987-01-01

    The development of screen-film mammography has resulted in the re-emergence of confidence, rather than fear, in mammography. When screen-film mammography is performed with state-of-the-art dedicated equipment utilizing vigorous breast compression and a ''soft'' x-ray beam for improved contrast, screen-film images are equivalent or superior to those of reduced-dose xeromammography and superior to those of nonscreen film mammography. Technological aids for conversion from xeromammographic or nonscreen film mammographic techniques to screen-film techniques have been described. Screen-film mammography should not be attempted until dedicated equipment has been obtained and the importance of vigorous compression has been understood

  10. Molecular HIV screening.

    Science.gov (United States)

    Bourlet, Thomas; Memmi, Meriam; Saoudin, Henia; Pozzetto, Bruno

    2013-09-01

    Nuclear acid testing is more and more used for the diagnosis of infectious diseases. This paper focuses on the use of molecular tools for HIV screening. The term 'screening' will be used under the meaning of first-line HIV molecular techniques performed on a routine basis, which excludes HIV molecular tests designed to confirm or infirm a newly discovered HIV-seropositive patient or other molecular tests performed for the follow-up of HIV-infected patients. The following items are developed successively: i) presentation of the variety of molecular tools used for molecular HIV screening, ii) use of HIV molecular tools for the screening of blood products, iii) use of HIV molecular tools for the screening of organs and tissue from human origin, iv) use of HIV molecular tools in medically assisted procreation and v) use of HIV molecular tools in neonates from HIV-infected mothers.

  11. Screening for abdominalt aortaaneurisme

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Juul, Søren; Henneberg, E W

    1997-01-01

    In spite of increasing number of elective resections of abdominal aortic aneurysms (AAA) the mortality or ruptured AAA is increasing. The advantages of elective operations are obvious; the lethality is 2-6% while the lethality of ruptured AAA is 75-95%. However, AAA seldom causes symptoms before...... rupture. Ultrasonographic screening for AAA takes 10 minutes per scan, and the sensitivity and specificity are high. Ultrasonographic screening for AAA is a reliable, safe and inexpensive method for screening, and screening for AAA is discussed worldwide. One point four percent of deaths among men from 65...... to 80 year of age are caused by ruptured AAA. Screening men over 65 for AAA can theoretically prevent a substantial number of deaths. Our calculations predict one prevented AAA-death per 200-300 scans for a cost of about 4000 DKK per saved year of life. However, cost-benefit analyses are based...

  12. Phytochemical screening and thin layer chromatography of the ...

    African Journals Online (AJOL)

    Phytochemical constituents of the leaves of Khaya senegalensis (dry zone mahogany) were determined in petroleum ether, chloroform, acetone and ethanol extracts. The screening revealed the presence of flavonoids, carbohydrates, glycosides, saponins, tannins, alkaloids and anthraquinones. Saponins and cardiac ...

  13. A cheap, simple high throughput method for screening native Helicobacter pylori urease inhibitors using a recombinant Escherichia coli, its validation and demonstration of Pistacia atlantica methanolic extract effectivity and specificity.

    Science.gov (United States)

    Amar, Natalie; Peretz, Avi; Gerchman, Yoram

    2017-02-01

    Helicobacter pylori is the most frequent and persistent bacterial infection worldwide, and a risk factor for active gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Although combined antibiotics treatment is effective cases of antibiotic resistance are reported at an alarming rate. The H. pylori urease enzyme is essential for the bacteria establishment in the gastric mucosa, resulting urease inhibitors being sought after as effective and specific anti- H. pylori treatment. To-date, screening assays are based mostly on the analog plant urease enzyme but difference in properties of the plant and bacterial enzymes hamper these efforts. We have developed a screening assay based on recombinant Escherichia coli expressing native H. pylori urease, and validated this assay using thiourea and a methanolic extract of Pistacia atlantica. The assay demonstrated the thiourea and the extract to be potent urease inhibitors, with the extract having strong bacteriostatic activity against clinical isolates of H. pylori, including such with antibiotic resistance. The extract was also found to be neutral toward common probiotic bacteria, supporting its specificity and compatibility with digestive system desired microflora and suggesting it could be a good source for anti-H. pylori compounds. The assay has proven to be cheap, simple and native alternative to the plant enzyme based assay and could allow for high throughput screening for new urease inhibitors and could expedite screening and development of novel, better H. pylori remedies helping us to combat this infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. The influence of time perspective on cervical cancer screening among Latinas in the United States.

    Science.gov (United States)

    Roncancio, Angelica M; Ward, Kristy K; Fernandez, Maria E

    2014-12-01

    To develop effective interventions to increase cervical cancer screening among Latinas, we should understand the role of cultural factors, such as time perspective, in the decision to be screened. We examined the relation between present time orientation, future time orientation, and self-reported cervical cancer screening among Latinas. A group of 206 Latinas completed a survey measuring factors associated with screening. Logistic regression analyses revealed that future time orientation was significantly associated with self-reported screening. Understanding the influence of time orientation on cervical cancer screening will assist us in developing interventions that effectively target time perspective and screening. © The Author(s) 2013.

  15. Screening for skin cancer.

    Science.gov (United States)

    Helfand, M; Mahon, S M; Eden, K B; Frame, P S; Orleans, C T

    2001-04-01

    Malignant melanoma is often lethal, and its incidence in the United States has increased rapidly over the past 2 decades. Nonmelanoma skin cancer is seldom lethal, but, if advanced, can cause severe disfigurement and morbidity. Early detection and treatment of melanoma might reduce mortality, while early detection and treatment of nonmelanoma skin cancer might prevent major disfigurement and to a lesser extent prevent mortality. Current recommendations from professional societies regarding screening for skin cancer vary. To examine published data on the effectiveness of routine screening for skin cancer by a primary care provider, as part of an assessment for the U.S. Preventive Services Task Force. We searched the MEDLINE database for papers published between 1994 and June 1999, using search terms for screening, physical examination, morbidity, and skin neoplasms. For information on accuracy of screening tests, we used the search terms sensitivity and specificity. We identified the most important studies from before 1994 from the Guide to Clinical Preventive Services, second edition, and from high-quality reviews. We used reference lists and expert recommendations to locate additional articles. Two reviewers independently reviewed a subset of 500 abstracts. Once consistency was established, the remainder were reviewed by one reviewer. We included studies if they contained data on yield of screening, screening tests, risk factors, risk assessment, effectiveness of early detection, or cost effectiveness. We abstracted the following descriptive information from full-text published studies of screening and recorded it in an electronic database: type of screening study, study design, setting, population, patient recruitment, screening test description, examiner, advertising targeted at high-risk groups or not targeted, reported risk factors of participants, and procedure for referrals. We also abstracted the yield of screening data including probabilities and numbers

  16. Preimplantation genetic screening.

    Science.gov (United States)

    Harper, Joyce C

    2018-03-01

    Preimplantation genetic diagnosis was first successfully performed in 1989 as an alternative to prenatal diagnosis for couples at risk of transmitting a genetic or chromosomal abnormality, such as cystic fibrosis, to their child. From embryos generated in vitro, biopsied cells are genetically tested. From the mid-1990s, this technology has been employed as an embryo selection tool for patients undergoing in vitro fertilisation, screening as many chromosomes as possible, in the hope that selecting chromosomally normal embryos will lead to higher implantation and decreased miscarriage rates. This procedure, preimplantation genetic screening, was initially performed using fluorescent in situ hybridisation, but 11 randomised controlled trials of screening using this technique showed no improvement in in vitro fertilisation delivery rates. Progress in genetic testing has led to the introduction of array comparative genomic hybridisation, quantitative polymerase chain reaction, and next generation sequencing for preimplantation genetic screening, and three small randomised controlled trials of preimplantation genetic screening using these new techniques indicate a modest benefit. Other trials are still in progress but, regardless of their results, preimplantation genetic screening is now being offered globally. In the near future, it is likely that sequencing will be used to screen the full genetic code of the embryo.

  17. Screening sensitivity theory

    International Nuclear Information System (INIS)

    Oblow, E.M.; Perey, F.G.

    1984-01-01

    A comprehensive rigorous theory is developed for screening sensitivity coefficients in largescale modeling applications. The theory uses Bayesian inference and group theory to establish a probabilistic framework for solving an underdetermined system of linear equations. The underdetermined problem is directly related to statistical screening sensitivity theory as developed in recent years. Several examples of the new approach to screening are worked out in detail and comparisons are made with statistical approaches to the problem. The drawbacks of these latter methods are discussed at some length

  18. Latent fingerprints on different type of screen protective films

    Directory of Open Access Journals (Sweden)

    Yuttana Sudjaroen

    2016-07-01

    Full Text Available The purpose of this research was to study the quality of latent fingerprint on different types of screen protective films including screen protector, matte screen protector, anti-fingerprint clear screen protector and anti-fingerprint matte screen protector by using black powder method in developing latent fingerprints. The fingerprints were performed by 10 volunteers whose fingers (right index, right thumb, left index and left thumb were stubbing at different types of screen protective films and subsequently latent fingerprints were developed by brushing with black powder. Automated Fingerprint Identification System (AFIS counted the numbers of minutiae points from 320 latent fingerprints. Anti-fingerprint matte screen protective film produced the best quality of latent fingerprint with an average minutiae point 72.65, followed by matte screen protective film, clear screen protective film and anti-fingerprint clear screen protective film with an average minutiae point of 155.2, 135.0 and 72.65 respectively. The quality of latent fingerprints developed between a clear and a matte surface of screen protective films showed a significant difference (sig>0.05, whereas the coat and the non-coat with anti-fingerprint chemical revealed a non-significant difference (sig<0.05 in their number of minutiae points.

  19. Risks of Colorectal Cancer Screening

    Science.gov (United States)

    ... Genetics of Colorectal Cancer Colorectal Cancer Screening Research Colorectal Cancer Screening (PDQ®)–Patient Version What is screening? Go ... These are called diagnostic tests . General Information About Colorectal Cancer Key Points Colorectal cancer is a disease in ...

  20. Cervical cancer - screening and prevention

    Science.gov (United States)

    Cancer cervix - screening; HPV - cervical cancer screening; Dysplasia - cervical cancer screening; Cervical cancer - HPV vaccine ... Almost all cervical cancers are caused by HPV (human papilloma virus). HPV is a common virus that spreads through sexual contact. Certain ...

  1. Two Novel Myoviruses from the North of Iraq Reveal Insights into Clostridium difficile Phage Diversity and Biology

    Directory of Open Access Journals (Sweden)

    Srwa J. Rashid

    2016-11-01

    Full Text Available Bacteriophages (phages are increasingly being explored as therapeutic agents to combat bacterial diseases, including Clostridium difficile infections. Therapeutic phages need to be able to efficiently target and kill a wide range of clinically relevant strains. While many phage groups have yet to be investigated in detail, those with new and useful properties can potentially be identified when phages from newly studied geographies are characterised. Here, we report the isolation of C. difficile phages from soil samples from the north of Iraq. Two myoviruses, CDKM15 and CDKM9, were selected for detailed sequence analysis on the basis of their broad and potentially useful host range. CDKM9 infects 25/80 strains from 12/20 C. difficile ribotypes, and CDKM15 infects 20/80 strains from 9/20 ribotypes. Both phages can infect the clinically relevant ribotypes R027 and R001. Phylogenetic analysis based on whole genome sequencing revealed that the phages are genetically distinct from each other but closely related to other long-tailed myoviruses. A comparative genomic analysis revealed key differences in the genes predicted to encode for proteins involved in bacterial infection. Notably, CDKM15 carries a clustered regularly interspaced short palindromic repeat (CRISPR array with spacers that are homologous to sequences in the CDKM9 genome and of phages from diverse localities. The findings presented suggest a possible shared evolutionary past for these phages and provides evidence of their widespread dispersal.

  2. Prostate Cancer Screening

    Science.gov (United States)

    ... treat. There is no standard screening test for prostate cancer. Researchers are studying different tests to find those ... PSA level may be high if you have prostate cancer. It can also be high if you have ...

  3. SCREENING FOR CERVICAL CANCER

    African Journals Online (AJOL)

    Enrique

    Cervical cancer remains a major health concern worldwide, especially in devel- ... Important aspects of cervical cancer screening include the age at which .... High-risk types HPV (16,18) are impli- cated in the pathogenesis of cervical cancer.

  4. Urine drug screen

    Science.gov (United States)

    Drug screen - urine ... detect the presence of illegal and some prescription drugs in your urine. Their presence may indicate that you recently used these drugs. Some drugs may remain in your system for ...

  5. Breast cancer screening

    International Nuclear Information System (INIS)

    Vandenbroucke, A.

    1987-01-01

    Many studies have shown that breast cancer screening is able to reduce breast cancer mortality, including the HIP study, the Swedish Trial and the Netherlands studies. Mammography is considered as the most effective method for breast cancer screening but it might be unfeasible for some reasons: - the population acceptability of the method might be low. Indeed, most populations of the South of Europe are less compliant to mass screening than populations of the North of Europe; - the medical equipment and personnel - radiologists and pathologists - might be insufficient; - it might be too costly for the National Health Service, specially where the incidence rate of breast cancer is relatively low (i.e. Greece, Portugal). The validity of screening tests is judged by their sensitivity and their specificity

  6. Neonatal cystic fibrosis screening test

    Science.gov (United States)

    Cystic fibrosis screening - neonatal; Immunoreactive trypsinogen; IRT test; CF - screening ... Cystic fibrosis is a disease passed down through families. CF causes thick, sticky mucus to build up in ...

  7. [Organized breast cancer screening].

    Science.gov (United States)

    Rouëssé, Jacques; Sancho-Garnier, Hélèn

    2014-02-01

    Breast screening programs are increasingly controversial, especially regarding two points: the number of breast cancer deaths they avoid, and the problem of over-diagnosis and over-treatment. The French national breast cancer screening program was extended to cover the whole country in 2004. Ten years later it is time to examine the risk/benefit ratio of this program and to discuss the need for change. Like all forms of cancer management, screening must be regularly updated, taking into account the state of the art, new evidence, and uncertainties. All screening providers should keep themselves informed of the latest findings. In the French program, women aged 50-74 with no major individual or familial risk factors for breast cancer are offered screening mammography and clinical breast examination every two years. Images considered non suspicious of malignancy by a first reader are re-examined by a second reader. The devices and procedures are subjected to quality controls. Participating radiologists (both public and private) are re