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Sample records for avium complex paradigm

  1. The Mycobacterium avium complex.

    PubMed Central

    Inderlied, C B; Kemper, C A; Bermudez, L E

    1993-01-01

    Mycobacterium avium complex (MAC) disease emerged early in the epidemic of AIDS as one of the common opportunistic infections afflicting human immunodeficiency virus-infected patients. However, only over the past few years has a consensus developed about its significance to the morbidity and mortality of AIDS. M. avium was well known to mycobacteriologists decades before AIDS, and the MAC was known to cause disease, albeit uncommon, in humans and animals. The early interest in the MAC provided a basis for an explosion of studies over the past 10 years largely in response to the role of the MAC in AIDS opportunistic infection. Molecular techniques have been applied to the epidemiology of MAC disease as well as to a better understanding of the genetics of antimicrobial resistance. The interaction of the MAC with the immune system is complex, and putative MAC virulence factors appear to have a direct effect on the components of cellular immunity, including the regulation of cytokine expression and function. There now is compelling evidence that disseminated MAC disease in humans contributes to both a decrease in the quality of life and survival. Disseminated disease most commonly develops late in the course of AIDS as the CD4 cells are depleted below a critical threshold, but new therapies for prophylaxis and treatment offer considerable promise. These new therapeutic modalities are likely to be useful in the treatment of other forms of MAC disease in patients without AIDS. The laboratory diagnosis of MAC disease has focused on the detection of mycobacteria in the blood and tissues, and although the existing methods are largely adequate, there is need for improvement. Indeed, the successful treatment of MAC disease clearly will require an early and rapid detection of the MAC in clinical specimens long before the establishment of the characteristic overwhelming infection of bone marrow, liver, spleen, and other tissue. Also, a standard method of susceptibility testing

  2. ELECTROPHORETIC MOBILITY OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS

    EPA Science Inventory

    The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms were measured. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1s-1, and the EPMs of fifteen environmental isolates ranged from -1...

  3. ELECTROPHORETIC MOBILITY OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS

    EPA Science Inventory

    The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms isolated from clinical and environmental sources were measured in 9.15 mM KH2PO4 buffered water. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1 ...

  4. Genotyping of Mycobacterium avium complex organisms using multispacer sequence typing.

    PubMed

    Cayrou, Caroline; Turenne, Christine; Behr, Marcel A; Drancourt, Michel

    2010-03-01

    Mycobacterium avium complex (MAC) currently comprises eight species of environmental and animal-associated, slowly-growing mycobacteria: Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium chimaera, Mycobacterium colombiense, Mycobacterium arosiense , Mycobacterium bouchedurhonense, Mycobacterium marseillense and Mycobacterium timonense. In humans, MAC organisms are responsible for opportunistic infections whose unique epidemiology remains poorly understood, in part due to the lack of a genotyping method applicable to all eight MAC species. In this study we developed multispacer sequence typing (MST), a sequencing-based method, for the genotyping of MAC organisms. An alignment of the genome sequence of M. avium subsp. hominissuis strain 104 and M. avium subsp. paratuberculosis strain K-10 revealed 621 intergenic spacers <1000 bp. From these, 16 spacers were selected that ranged from 300 to 800 bp and contained a number of variable bases, <50 within each of the 16 spacers. Four spacers were successfully PCR-amplified and sequenced in 11 reference strains. Combining the sequence of these four spacers in 106 MAC organisms, including 83 M. avium, 11 M. intracellulare , six M. chimaera, two M. colombiense and one each of M. arosiense, M. bouchedurhonense, M. marseillense and M. timonense, yielded a total of 45 spacer types, with an index of discrimination of 0.94. Each spacer type was specific for a species and certain spacer types were specific for subspecies of M. avium. MST is a new method for genotyping of organisms belonging to any one of the eight MAC species tested in this study.

  5. Genetic relatedness among Mycobacterium paratuberculosis and M. avium complex.

    PubMed

    Labidi, A; Thoen, C O

    1989-01-01

    Total DNA was extracted from M. paratuberculosis (ATCC 19698) and from M. avium complex (ATCC 25291) cultivated on RVB-10 enriched liquid media. Restriction endonuclease analysis of total DNA was performed with 34 enzymes and DNA digestion profiles were compared. Fifteen enzymes revealed important differences between the two species. Two pairs of enzymes (EcoRII, BstNI) and (MboI, Sau3AI) provide evidence for the presence of dcmI and dam methylation in DNA of M. avium complex and M. paratuberculosis. The differences in DNA fragments of these two species could be of potential value in differentiating these clinically significant mycobacteria.

  6. GENETIC FINGERPRINTING OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS ISOLATED FROM HOSPITAL PATIENTS AND THE ENVIRONMENT

    EPA Science Inventory

    A particularly pathogenic group of mycobacteria belong to the Mycobacterium avium complex (MAC), which includes M. avium and M. intracellulare. MAC organisms cause disease in children, the elderly, and immuno-compromised individuals. A critical step in preventing MAC infections...

  7. Mycobacterium avium Complex Cervical Lymphadenitis in an Immunocompetent Adult▿

    PubMed Central

    Christensen, Joshua B.; Koeppe, John

    2010-01-01

    Nontuberculosis mycobacterial cervical lymphadenitis is a relatively common disease in immunocompetent children but a rare disease in immunocompetent adults. We report the diagnosis and treatment of Mycobacterium avium complex cervical lymphadenitis in an adult female. Our evaluation of immune competence, including gamma interferon (IFN-γ) and interleukin-12 (IL-12) signaling, found no evidence of deficiency. PMID:20668140

  8. In Vitro Susceptibility Testing of Bedaquiline against Mycobacterium avium Complex.

    PubMed

    Brown-Elliott, Barbara A; Philley, Julie V; Griffith, David E; Thakkar, Foram; Wallace, Richard J

    2017-02-01

    We performed bedaquiline broth microdilution susceptibility testing using Clinical and Laboratory Standards Institute (CLSI) guidelines on 103 respiratory isolates of Mycobacterium avium complex (MAC), including multidrug-resistant isolates. Approximately 90% of isolates had bedaquiline MICs of ≤0.008 μg/ml, and 102/103 isolates had MICs of ≤0.015 μg/ml. Bedaquiline has excellent potential for use in patients with MAC infections, although for reasons of its metabolism by the cytochrome P450 system, it should not be given with rifampin.

  9. Characterization of Mouse Models of Mycobacterium avium Complex Infection and Evaluation of Drug Combinations

    PubMed Central

    Almeida, Deepak V.; Tyagi, Sandeep; Converse, Paul J.; Ammerman, Nicole C.; Grosset, Jacques H.

    2015-01-01

    The Mycobacterium avium complex is the most common cause of nontuberculous mycobacterial lung disease worldwide; yet, an optimal treatment regimen for M. avium complex infection has not been established. Clarithromycin is accepted as the cornerstone drug for treatment of M. avium lung disease; however, good model systems, especially animal models, are needed to evaluate the most effective companion drugs. We performed a series of experiments to evaluate and use different mouse models (comparing BALB/c, C57BL/6, nude, and beige mice) of M. avium infection and to assess the anti-M. avium activity of single and combination drug regimens, in vitro, ex vivo, and in mice. In vitro, clarithromycin and moxifloxacin were most active against M. avium, and no antagonism was observed between these two drugs. Nude mice were more susceptible to M. avium infection than the other mouse strains tested, but the impact of treatment was most clearly seen in M. avium-infected BALB/c mice. The combination of clarithromycin-ethambutol-rifampin was more effective in all infected mice than moxifloxacin-ethambutol-rifampin; the addition of moxifloxacin to the clarithromycin-containing regimen did not increase treatment efficacy. Clarithromycin-containing regimens are the most effective for M. avium infection; substitution of moxifloxacin for clarithromycin had a negative impact on treatment efficacy. PMID:25624335

  10. Proteins : paradigms of complexity /

    SciTech Connect

    Frauenfelder, Hans,

    2001-01-01

    Proteins are the working machines of living systems. Directed by the DNA, of the order of a few hundred building blocks, selected from twenty different amino acids, are covalently linked into a linear polypeptide chain. In the proper environment, the chain folds into the working protein, often a globule of linear dimensions of a few nanometers. The biologist considers proteins units from which living systems are built. Many physical scientists look at them as systems in which the laws of complexity can be studied better than anywhere else. Some of the results of such studies will be sketched.

  11. Draft genome sequence of a Mycobacterium avium complex isolate from a broadbill bird

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report the draft genome sequences of ten Mycobacterium avium complex isolates obtained from diverse hosts. This collection includes isolates obtained from deer, pig, elephant, ruddy duck and Red-tailed hawk species. The type strain of Mycobacterium avium subspecies silvaticum (ATCC 49884) is also...

  12. REAL-TIME QUANTITATIVE PCR DETECTION OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS IN DRINKING WATER

    EPA Science Inventory

    The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and others. MAC are listed on the U.S. Environmental Protection Agency's Contaminant Candidate List (CCL) due to their association with human disease and occurrence in public drinkin...

  13. Detection of quantification of Mycobacterium avium complex organisms in drinking water

    EPA Science Inventory

    The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and others. MAC are listed on the U. S. Environmental Protection Agency’s Contaminant Candidate List 2 (CCL2) due to their association with human disease and occurrence in public dr...

  14. Evaluation of Vitek MS for rapid classification of clinical isolates belonging to Mycobacterium avium complex.

    PubMed

    Boyle, Daniel P; Zembower, Teresa R; Qi, Chao

    2015-01-01

    We evaluated the ability of the Vitek MS system to classify clinical pulmonary Mycobacterium avium complex isolates compared to multilocus sequence analysis. Vitek MS accurately identified 55% of the isolates as M. avium and 18% as M. intracellulare, but misidentified 24 (27%) Mycobacterium chimaera isolates as Mycobacterium intracellulare.

  15. AMPLIFIED FRAGMENT LENGTH POLYMORPHISM ANALYSIS OF MYCOBACTERIUM AVIUM COMPLEX ISOLATES RECOVERED FROM SOUTHERN CALIFORNIA

    EPA Science Inventory

    Fine-scale genotyping methods are necessary in order to identify possible sources of human exposure to opportunistic pathogens belonging to the Mycobacterium avium complex (MAC). In this study, amplified fragment length polymorphism (AFLP) analysis was evaluated for fingerprintin...

  16. Infection of Eurasian badgers (Meles meles) with Mycobacterium avium complex (MAC) bacteria.

    PubMed

    Balseiro, Ana; Merediz, Isabel; Sevilla, Iker A; García-Castro, Carmen; Gortázar, Christian; Prieto, José M; Delahay, Richard J

    2011-05-01

    There are few reports of infection with Mycobacterium avium complex (MAC) bacteria in badgers. In this study archive data relating to the isolation of MAC organisms from badgers in the UK is presented, and information derived from recent cases of such infection in Spain is used to illustrate the associated pathology and to characterise strain types. Tissue samples were cultured for mycobacteria and, in the case of Spanish badgers, were examined both histopathologically and using immunohistochemistry, and DNA typing of M. avium isolates was also carried out. A total of 5 (7.35%) and 281 (0.51%) isolates of M. avium spp. were recovered from badgers from the studies in Spain and the UK, respectively. DNA typing of the isolates from Spain identified the sub-species M. avium hominissuis and M. avium avium. These findings provide new information on the prevalence of MAC organisms in badgers in the UK and Spain. The extent to which infected badgers may be involved in the epidemiology of M. avium in other wild or domestic hosts remains unknown.

  17. Distribution of IS901 in strains of Mycobacterium avium complex from swine by using IS901-detecting primers that discriminate between M. avium and Mycobacterium intracellulare.

    PubMed

    Nishimori, K; Eguchi, M; Nakaoka, Y; Onodera, Y; Ito, T; Tanaka, K

    1995-08-01

    The presence of the mycobacterial insertion sequence IS901 was studied by PCR with reference strains of Mycobacterium avium complex; 122 veterinary strains of mycobacteria, mainly M. avium complex, isolated from swine; and 15 clinical strains. Four kinds of DNA extraction methods for PCR were compared. Use of the commercial extraction matrix allowed for the faster and easier preparation of PCR-amplifiable DNA than use of NaOH heating extraction or sodium dodecyl sulfate extraction of pretreated mycobacteria. It also provided more effective protection than boiling extraction against the destruction of DNA. Four reference strains of serovars 1 to 3 possessed IS901. Nine reference strains of serovars 1, 4 to 6, 8 to 11, and 21 possessed only IS901 insertion sites. A novel PCR product was found in the other reference strains of serovars 7, 12 to 17, 19, and 20 and two clinical strains of serovar 15. It is suggested that the primers that amplified the insertion portion of IS901 divided the M. avium complex into M. avium, Mycobacterium intracellulare, and other mycobacteria. None of the 110 strains of M. avium complex isolated from swine possessed IS901. It is suggested that the absence of IS901 might be characteristic of swine-derived strains of M. avium complex.

  18. Species identification of Mycobacterium avium complex isolates by a variety of molecular techniques.

    PubMed

    Beggs, M L; Stevanova, R; Eisenach, K D

    2000-02-01

    Organisms in the Mycobacterium avium complex (MAC; M. avium, M. intracellulare, and "nonspecific or X" MAC) are emerging pathogens among individual organisms of which significant genetic variability is displayed. The objective of the present study was to evaluate various molecular methods for the rapid and definitive identification of MAC species. Isolates were obtained from both human immunodeficiency virus (HIV)-positive patients and HIV-negative patients with and without known predisposing conditions. The isolates were initially hybridized with nucleic acid probes complementary to the rRNA of the respective mycobacterial species (AccuProbe Culture Confirmation kits for M. avium, M. intracellulare, and MAC species; Gen-Probe). Isolates were also examined by PCR and in some cases by Southern blot hybridization for the insertion element IS1245. Two other techniques included a PCR assay that amplifies the mig gene, a putative virulence factor for MAC, and hsp65 gene amplification and sequencing. This study led to the following observations. Eighty-five percent of the isolates from HIV-positive patients were M. avium and 86% of the isolates from HIV-negative patients were M. intracellulare. Fifteen of the M. avium isolates did not contain IS1245 and 7% of the M. intracellulare isolates were found to carry IS1245. All of the M. avium strains were mig positive, and all of the M. intracellulare strains were mig negative.

  19. Proposal to elevate Mycobacterium avium complex ITS sequevar MAC-Q to Mycobacterium vulneris sp. nov.

    PubMed

    van Ingen, J; Boeree, M J; Kösters, K; Wieland, A; Tortoli, E; Dekhuijzen, P N R; van Soolingen, D

    2009-09-01

    The Mycobacterium avium complex (MAC) consists of four recognized species, Mycobacterium avium, Mycobacterium colombiense, Mycobacterium intracellulare and Mycobacterium chimaera, and a variety of other strains that may be members of undescribed taxa. We report on two isolates of a scotochromogenic, slowly growing, non-tuberculous Mycobacterium species within the M. avium complex from a lymph node and an infected wound after a dogbite of separate patients in The Netherlands. The extrapulmonary infections in immunocompetent patients suggested a high level of virulence. These isolates were characterized by a unique nucleotide sequence in the 16S rRNA gene, 99% similar to Mycobacterium colombiense, and the MAC-Q 16S-23S internal transcribed spacer (ITS) sequence. Sequence analyses of the hsp65 gene revealed 97% similarity to M. avium. The rpoB gene sequence was 98% similar to M. colombiense. Phenotypically, the scotochromogenicity, positive semi-quantitative catalase and heat-stable catalase tests, negative tellurite reductase and urease tests and susceptibility to hydroxylamine and oleic acid set these isolates apart from related species. High-performance liquid chromatography analysis of cell-wall mycolic acid content revealed a unique pattern, related to that of M. avium and M. colombiense. Together, these findings supported a separate species status within the Mycobacterium avium complex. We propose elevation of scotochromogenic M. avium complex strains sharing this 16S gene and MAC-Q ITS sequence to separate species status, for which the name Mycobacterium vulneris sp. nov. is proposed. The type strain is NLA000700772T (=DSM 45247T=CIP 109859T).

  20. Whole chromosomal DNA probes for rapid identification of Mycobacterium tuberculosis and Mycobacterium avium complex.

    PubMed Central

    Roberts, M C; McMillan, C; Coyle, M B

    1987-01-01

    Whole chromosomal DNA probes were used to identify clinical isolates of Mycobacterium tuberculosis, Mycobacterium avium complex, and Mycobacterium gordonae. The probe for M. tuberculosis was prepared from Mycobacterium bovis BCG, which has been shown to be closely related to M. tuberculosis. A probe for the M. avium complex was prepared from three strains representing each of the three DNA homology groups in the M. avium complex. The probes were used in dot blot assays to identify clinical isolates of mycobacteria. The dot blot test correctly identified 57 of the 61 (93%) cultures grown on solid media, and 100% of antibiotic-treated broth-grown cells were correctly identified. Identification by dot blot required a maximum of 48 h. When the probes were tested against 63 positive BACTEC (Johnston Laboratories, Inc., Towson, Md.) cultures of clinical specimens, 59% were correctly identified. However, of the 14 BACTEC cultures that had been treated with antibiotics before being lysed, 13 (93%) were correctly identified. PMID:3112180

  1. Thioridazine as Chemotherapy for Mycobacterium avium Complex Diseases

    PubMed Central

    Deshpande, Devyani; Srivastava, Shashikant; Musuka, Sandirai

    2016-01-01

    Mycobacterium avium-intracellulare complex (MAC) causes an intractable intracellular infection that presents as chronic pulmonary disease. Currently, therapy consists of ethambutol and macrolides and takes several years to complete. The neuroleptic phenothiazine thioridazine kills mycobacteria by inhibiting the electron transport chain. In several experiments with bacterial populations of up to 1012 CFU/ml, we failed to isolate any bacteria resistant to 3 times the MIC of thioridazine, suggesting the absence of resistant mutants at bacterial burdens severalfold higher than those encountered in patients. In the hollow-fiber model of intracellular MAC (HFS-MAC), thioridazine achieved an extracellular half-life of 16.8 h and an intracellular half-life of 19.7 h. Thioridazine concentrations were >28,000-fold higher inside infected macrophages than in the HFS-MAC central compartment (equivalent to plasma). Thioridazine maximal kill was 5.20 ± 0.75 log10 CFU/ml on day 7 (r2 = 0.96) and 7.19 ± 0.31 log10 CFU/ml on day 14 (r2 = 0.99), the highest seen with any drug in the system. Dose fractionation studies revealed that thioridazine efficacy and acquired drug resistance were driven by the peak concentation-to-MIC ratio, with a 50% effective concentration (EC50) of 2.78 ± 0.44 for microbial killing. Acquired drug resistance was encountered by day 21 with suboptimal doses, demonstrating that fluctuating drug concentrations drive evolution faster than static concentrations in mutation frequency studies. However, the thioridazine EC50 changed 16.14-fold when the concentration of fetal bovine serum was changed from 0% to 50%, suggesting that intracellular potency could be heavily curtailed by protein binding. Efficacy in patients will depend on the balance between trapping of the drug in the pulmonary system and the massive intracellular concentrations versus very high protein binding of thioridazine. PMID:27216055

  2. Zoonotic aspects of Mycobacterium bovis and Mycobacterium avium-intracellulare complex (MAC).

    PubMed

    Biet, Franck; Boschiroli, Maria Laura; Thorel, Marie Françoise; Guilloteau, Laurence A

    2005-01-01

    Pathogens that are transmitted between the environment, wildlife, livestock and humans represent major challenges for the protection of human and domestic animal health, the economic sustainability of agriculture, and the conservation of wildlife. Among such pathogens, the genus Mycobacterium is well represented by M. bovis, the etiological agent of bovine tuberculosis, M. avium ssp. paratuberculosis (Map) the etiological agent of Johne disease, M. avium ssp. avium (Maa) and in a few common cases by other emergent environmental mycobacteria. Epidemiologic surveys performed in Europe, North America and New Zealand have demonstrated the existence and importance of environmental and wildlife reservoirs of mycobacterial infections that limit the attempts of disease control programmes. The aim of this review is to examine the zoonotic aspects of mycobacteria transmitted from the environment and wildlife. This work is focused on the species of two main groups of mycobacteria classified as important pathogens for humans and animals: first, M. bovis, the causative agent of bovine tuberculosis, which belongs to the M. tuberculosis complex and has a broad host range including wildlife, captive wildlife, domestic livestock, non-human primates and humans; the second group examined, is the M. avium-intracellulare complex (MAC) which includes M. avium ssp. avium causing major health problems in AIDS patients and M. avium ssp. paratuberculosis the etiological agent of Johne disease in cattle and identified in patients with Crohn disease. MAC agents, in addition to a broad host range, are environmental mycobacteria found in numerous biotopes including the soil, water, aerosols, protozoa, deep litter and fresh tropical vegetation. This review examines the possible reservoirs of these pathogens in the environment and in wildlife, their role as sources of infection in humans and animals and their health impact on humans. The possibilities of control and management programmes for

  3. Assessing the effectiveness of low-pressure ultraviolet light for inactivating Mycobacterium avium complex (MAC) micro-organisms

    EPA Science Inventory

    Aims: To assess low-pressure ultraviolet light (LP-UV) inactivation kinetics of Mycobacterium avium complex (MAC) strains in a water matrix using collimated beam apparatus. Methods and Results: Strains of M. avium (n = 3) and Mycobacterium intracellulare (n = 2) were exposed t...

  4. Envelope protein complexes of Mycobacterium avium subsp. paratuberculosis and their antigenicity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne’s disease, a chronic enteric disease of ruminant animals. In the present study, blue native PAGE electrophoresis and 2D SDS-PAGE were used to separate MAP envelope protein complexes, followed by mass spectrometry (MS) ...

  5. Structure of a New Glycolipid from the Mycobacterium avium-Mycobacterium intracellulare Complex

    PubMed Central

    Watanabe, Motoko; Ohta, Akihiro; Sasaki, Shun-ichi; Minnikin, David E.

    1999-01-01

    From the lipid fraction of a freeze-dried cell mass of a strain of the Mycobacterium avium-Mycobacterium intracellulare complex, a new glycolipid was isolated and was characterized as 5-mycoloyl-α-arabinofuranosyl (1→1′)-glycerol, mainly on the basis of nuclear magnetic resonance spectroscopy studies. PMID:10094713

  6. Improved detection of Mycobacterium avium complex with the Bactec radiometric system

    SciTech Connect

    Hoffner, S.E.

    1988-05-01

    A reconsideration of the laboratory methods used for primary isolation of mycobacteria other than Mycobacterium tuberculosis is needed due to the increasingly recognized importance of such mycobacterial infections in immunocompromised patients. One example of this is the severe opportunistic infections caused by Mycobacterium avium complex among AIDS patients. In this study, the Bactec radiometric system was compared to conventional culture on solid medium for the detection of M. avium complex in 3,612 selected clinical specimens, mainly of extrapulmonary origin. Of a total number of 63 M. avium complex isolates, the Bactec system detected 58 (92%), compared to 37 (59%) for conventional culture. A much more rapid detection was attained with radiometric technique than with conventional culture. The mean detection time for the cultures positive with both methods was 7.1 and 28.3 days, respectively. The Bactec radiometric system achieves a rapid and significantly more sensitive detection and seems to be an excellent complement to conventional culture in the laboratory diagnosis of infections with the M. avium complex.

  7. Efficient Differentiation of Mycobacterium avium Complex Species and Subspecies by Use of Five-Target Multiplex PCR▿

    PubMed Central

    Shin, Sung Jae; Lee, Byung Soo; Koh, Won-Jung; Manning, Elizabeth J. B.; Anklam, Kelly; Sreevatsan, Srinand; Lambrecht, Randall S.; Collins, Michael T.

    2010-01-01

    Infections caused by the Mycobacterium avium complex (MAC) are on the rise in both human and veterinary medicine. A means of effectively discriminating among closely related yet pathogenetically diverse members of the MAC would enable better diagnosis and treatment as well as further our understanding of the epidemiology of these pathogens. In this study, a five-target multiplex PCR designed to discriminate MAC organisms isolated from liquid culture media was developed. This MAC multiplex was designed to amplify a 16S rRNA gene target common to all Mycobacterium species, a chromosomal target called DT1 that is unique to M. avium subsp. avium serotypes 2 and 3, to M. avium subsp. silvaticum, and to M. intracellulare, and three insertion sequences, IS900, IS901, and IS1311. The pattern of amplification results allowed determination of whether isolates were mycobacteria, whether they were members of the MAC, and whether they belonged to one of three major MAC subspecies, M. avium subsp. paratuberculosis, M. avium subsp. avium, and M. avium subsp. hominissuis. Analytical sensitivity was 10 fg of M. avium subsp. paratuberculosis genomic DNA, 5 to 10 fg of M. avium subsp. avium genomic DNA, and 2 to 5 fg of DNA from other mycobacterial species. Identification accuracy of the MAC multiplex was evaluated by testing 53 bacterial reference strains consisting of 28 different mycobacterial species and 12 nonmycobacterial species. Identification accuracy in a clinical setting was evaluated for 223 clinical MAC isolates independently identified by other methods. Isolate identification agreement between the MAC multiplex and these comparison assays was 100%. The novel MAC multiplex is a rapid, reliable, and simple assay for discrimination of MAC species and subspecies in liquid culture media. PMID:20810779

  8. Comparison of four culture media for isolation of Mycobacterium avium complex from porcine tissues.

    PubMed

    Thoen, C O; Himes, E M; Jarnagin, J L; Harrington, R

    1979-02-01

    The efficiency of four culture media was compared for the isolation of Mycobacterium avium complex from 197 procine tissues. In 82 tissues with microscopic granulomas and acid-fast bacilli, a significantly greater number of isolates were obtained on Middlebrook 7H10 medium with sodium pyruvate than on Stonebrink medium, Herrold egg yolk agar medium, or Lowenstein-Jensen medium (P=0.01). In 46 tissues in which no microscopic granulomas or acid-fast bacilli were observed, a significantly greater number of isolates were made on Middlebrook 7H10 medium or Herrold egg yolk agar medium than on Stonebrink medium or on Lowenstein-Jensen medium (P=0.01). The time required to grow M. avium complex on Lowenstein-Jensen medium was significantly greater than the time required to observe growth on Stonebrink, Middlebrook 7H10, or Herrold egg yolk agar medium (p=0.001).

  9. Cnn: a Paradigm for Complexity

    NASA Astrophysics Data System (ADS)

    Chua, Leon O.

    The following sections are included: * What is a CNN? * Part I: Standard CNNs * Standard CNNs are uniquely specified by CNN genes * Oscillations and chaos from standard CNNs * Complete stability criteria for standard CNNs * Bistable criterion * Coding the CNN gene * Edge detection CNN * Corner detection CNN * A gallery of basic CNN genes * Does there exist a CNN gene for solving Minsky's global connectivity problem? * Decoding the CNN gene * Examples of input-output CNN operators * Uncoupled CNN genes * Boolean CNN genes and truth tables * What task can an uncoupled Boolean CNN gene Perform? * Bifurcation of CNN genes * The game-of-life CNN gene * The CNN universal machine * Generalized cellular automata * A glimpse at some real-world CNN applications * Part II: Autonomous CNNs * Pattern formation in standard CNNs * Characterization of stable equilibria * The dynamics of pattern formation * CNN pattern formation in biology and physics * Pattern formation in reaction-diffusion CNNs * Nonlinear waves in reaction-diffusion CNNs * Simulating nonlinear PDEs via autonomous CNNs * Part III: Local Activity: The Genesis of Complexity * Transistors and local activity: What do they have to common? * Nonlinear circuit models for reaction-diffusion CNNs * What is local activity? * Cell equilibrium points * Local state equations and local power flows * Local activity in reaction-diffusion CNN cells * Testing for local activity * Testing one-port CNN cells for local activity * Testing two-port CNN cells for local activity * Why is local activity necessary for pattern formation? * How to choose locally-active CNN parameters? * Local activity and stability are different concepts * The local activity dogma

  10. Multilocus enzyme electrophoresis analysis of the Mycobacterium avium complex and other mycobacteria.

    PubMed Central

    Wasem, C F; McCarthy, C M; Murray, L W

    1991-01-01

    Multilocus enzyme electrophoresis analysis was used to evaluate the Mycobacterium avium complex (MAC), M. paratuberculosis, and nine other mycobacterial species. The average number of alleles per locus was 2.8 for the 35 MAC and 2 M. paratuberculosis strains which represented 24 electrophoretic types (ETs) and two distinct groups. The M. avium group was resolved into 17 ETs and contained the M. paratuberculosis ET. The M. intracellulare group consisted of six ETs. There was complete agreement between Gen-Probe identification and group placement by multilocus enzyme electrophoresis. The mean genetic diversity per locus for the 24 MAC ETs was 0.38. This procedure subdivided some serovars and, if implemented, should prove to be a powerful epidemiologic tool for the MAC. Eleven additional ETs were formed after the data for the other mycobacterial species were pooled with those for the MAC. PMID:2007633

  11. Mycobacteriosis in ostriches (Struthio camelus) due to infection with Mycobacterium bovis and Mycobacterium avium complex.

    PubMed

    Kelly, Pamela; Jahns, Hanne; Power, Eugene; Bainbridge, John; Kenny, Kevin; Corpa, Juan M; Cassidy, Joseph P; Callanan, John J

    2013-12-01

    Avian tuberculosis rarely affects ratites compared to other bird species and is typically caused by Mycobacterium avium species. This study describes the pathological and microbiological findings in three adult ostriches with mycobacteriosis, in one of which Mycobacterium bovis was isolated from the lesions. Post mortem examinations on ostriches from two different zoological collections in Ireland revealed multifocal caseous granulomas affecting the spleen and liver in all cases, with additional involvement of intestines in two cases. In one case, granulomas were present within the pharynx, at the thoracic inlet and multifocally on the pleural surface. Acid-fast bacilli were observed in all lesions. Mycobacterium sp. of the M. avium complex was isolated from the intestinal lesions in the two cases with intestinal involvement, and M. bovis sp. oligotype SB0140 was cultured from the liver of the third ostrich. This represents the first reported case of M. bovis infection in an ostrich. Avian tuberculosis due to M. bovis is rare and to date has been reported in only parrots and experimentally inoculated birds. Mycobacterium bovis needs to be considered as a possible cause of tuberculosis in ostriches because the lesions are similar to those observed with M. avium complex infection.

  12. Experimental Reactivation of Pulmonary Mycobacterium avium Complex Infection in a Modified Cornell-Like Murine Model

    PubMed Central

    Kim, Woo Sik; Kim, Jong-Seok; Kim, Hong Min; Kwon, Kee Woong; Cho, Sang-Nae; Shin, Sung Jae; Koh, Won-Jung

    2015-01-01

    The latency and reactivation of Mycobacterium tuberculosis infection has been well studied. However, there have been few studies of the latency and reactivation of Mycobacterium avium complex (MAC), the most common etiological non-tuberculous Mycobacterium species next to M. tuberculosis in humans worldwide. We hypothesized that latent MAC infections can be reactivated following immunosuppression after combination chemotherapy with clarithromycin and rifampicin under experimental conditions. To this end, we employed a modified Cornell-like murine model of tuberculosis and investigated six strains consisting of two type strains and four clinical isolates of M. avium and M. intracellulare. After aerosol infection of each MAC strain, five to six mice per group were euthanized at 2, 4, 10, 18, 28 and 35 weeks post-infection, and lungs were sampled to analyze bacterial burden and histopathology. One strain of each species maintained a culture-negative state for 10 weeks after completion of 6 weeks of chemotherapy, but was reactivated after 5 weeks of immunosuppression in the lungs with dexamethasone (three out of six mice in M. avium infection) or sulfasalazine (four out of six mice in both M. avium and M. intracellulare infection). The four remaining MAC strains exhibited decreased bacterial loads in response to chemotherapy; however, they remained at detectable levels and underwent regrowth after immunosuppression. In addition, the exacerbated lung pathology demonstrated a correlation with bacterial burden after reactivation. In conclusion, our results suggest the possibility of MAC reactivation in an experimental mouse model, and experimentally demonstrate that a compromised immune status can induce reactivation and/or regrowth of MAC infection. PMID:26406237

  13. Cell-free system responsible for internal radiolabeling of glycopeptidolipids of the Mycobacterium avium complex.

    PubMed Central

    Ramasesh, N; Wright, E L; Barrow, W W

    1992-01-01

    Internal radiolabeling of serotype-specific glycopeptidolipids with [14C]mannose was accomplished with a cell-free system derived from serotype 20 of the Mycobacterium avium complex. Similar radiolabeling was not apparent with a cell-free system derived from the rough colony variant, previously shown to be devoid of glycopeptidolipids. Although a comparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein analysis of the parent and rough variant strains revealed a close similarity, there were some proteins unique to the parent strain. Images PMID:1729193

  14. Characterization of total deoxyribonucleic acid of Mycobacterium paratuberculosis (ATCC 19698) and of M. avium complex (ATCC 25291) using restriction enzymes.

    PubMed

    Labidi, A

    1988-01-01

    Total DNA was extracted from M. paratuberculosis (ATCC 19698) and from M. avium complex (ATCC 25291) cultivated on RVB-10 enriched liquid media. Restriction endonuclease analysis was conducted of Total DNA using 34 enzymes and DNA digestion profiles were compared. Fifteen enzymes revealed important differences between the two species. Two pairs of enzymes (EcoRII, BstNI) and (MboI, Sau3AI) provide evidence for the presence of dcmI and dam methylation in DNA of M. avium complex and M. paratuberculosis. The differences in DNA fragments of these two species could be of potential value in differentiating these clinically significant mycobacteria.

  15. THE ISOLATION AND IDENTIFICATION OF MYCOBACTERIUM AVIUM COMPLEX (MAC) RECOVERED FROM LOS ANGELES POTABLE WATER, A POSSIBLE SOURCE OF INFECTION IN AIDS PATIENTS

    EPA Science Inventory

    Los Angeles water was investigated as a possible source of Mycobacterium avium complex (MAC) infection in patients with AIDS. MAC consists of M.avium (MA), M. intracellulare (MI) and Mycobacterium X (MX)(positive for MAC by DNA probe but not MA or MI). The study included 13 reser...

  16. Modified lymphocyte response to mitogens after intraperitoneal injection of glycopeptidolipid antigens from Mycobacterium avium complex.

    PubMed Central

    Brownback, P E; Barrow, W W

    1988-01-01

    Intraperitoneal injection of glycopeptidolipid (GPL) antigens from Mycobacterium avium complex serovar 4 resulted in the decreased ability of murine splenic lymphocytes to respond to nonspecific-mitogen-induced blastogenesis when exposed to concanavalin A, phytohemagglutinin, and lipopolysaccharide. Adherent cell depletion and cell mixing experiments with T lymphocytes indicated that macrophages were not a major contributor to the immunosuppression observed in this study. Enumeration of splenic lymphocytes by means of flow-cytometry with fluorescein isothiocyanate-conjugated monoclonal antibodies demonstrated that intraperitoneal injection of GPL antigens resulted in a significant decrease in Thy-1+ and Lyt-1+ cells but no change in the numbers of Lyt-2+ cells. Treatment with GPL antigens in vitro affected the ability of splenic mononuclear cells to respond optimally for concanavalin A-induced blastogenesis at 40 micrograms of GPL per 4 X 10(5) cells per 0.2 ml and lipopolysaccharide-induced blastogenesis at concentrations ranging from 5 to 40 micrograms of GPL per 4 X 10(5) cells per 0.2 ml. However, in vitro treatment with GPL antigens did not affect phytohemagglutinin-induced blastogenesis at concentrations ranging from 5 to 40 micrograms of GPL per 4 X 10(5) cells per 0.2 ml. These findings suggest that GPL antigens or their metabolites affect lymphocyte function and may be important cofactors in the overall pathogenesis of M. avium complex infections. PMID:3258582

  17. Culture and molecular method for detection of Mycobacterium tuberculosis complex and Mycobacterium avium subsp. paratuberculosis in milk and dairy products.

    PubMed

    Messelhäusser, U; Kämpf, P; Hörmansdorfer, S; Wagner, B; Schalch, B; Busch, U; Höller, C; Wallner, P; Barth, G; Rampp, A

    2012-01-01

    A combined molecular and cultural method for the detection of the Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium subsp. paratuberculosis was developed and tested with artificially contaminated milk and dairy products. Results indicate that the method can be used for a reliable detection as a basis for first risk assessments.

  18. rpoB sequence-based identification of Mycobacterium avium complex species.

    PubMed

    Ben Salah, Iskandar; Adékambi, Toidi; Raoult, Didier; Drancourt, Michel

    2008-12-01

    The Mycobacterium avium complex (MAC) comprises slowly growing mycobacteria responsible for opportunistic infections and zoonoses. The ability to speciate MAC isolates in the clinical microbiology laboratory is critical for determining the organism implicated in clinical disease and for epidemiological investigation of the source of infection. Investigation of a 711 bp variable fragment of rpoB flanked by the Myco-F/Myco-R primers found a 0.7-5.1 % divergence among MAC reference strains, with Mycobacterium chimaera and Mycobacterium intracellulare being the most closely related. Using a 0.7 % divergence cut-off, 83 % of 100 clinical isolates, which had been previously identified by phenotypic characteristics and 16S-23S rDNA intergenic spacer (ITS) probing, were identified as M. avium, 8 % as M. intracellulare and 2 % as M. chimaera. The uniqueness of seven isolates, exhibiting < 99.3 % rpoB sequence similarity with MAC reference strains, was confirmed by 16S rDNA, ITS and hsp65 sequencing and phylogenetic analyses. Partial rpoB gene sequencing using the Myco-F/Myco-R primers permits one-step identification of MAC isolates at the species level and the detection of potentially novel MAC species.

  19. Mycobacterium avium complex in day care hot water systems, and persistence of live cells and DNA in hot water pipes.

    PubMed

    Bukh, Annette S; Roslev, Peter

    2014-04-01

    The Mycobacterium avium complex (MAC) is a group of opportunistic human pathogens that may thrive in engineered water systems. MAC has been shown to occur in drinking water supplies based on surface water, but less is known about the occurrence and persistence of live cells and DNA in public hot water systems based on groundwater. In this study, we examined the occurrence of MAC in hot water systems of public day care centers and determined the persistence of live and dead M. avium cells and naked DNA in model systems with the modern plumbing material cross-linked polyethylene (PEX). The occurrence of MAC and co-occurrence of Legionella spp. and Legionella pneumophila were determined using cultivation and qPCR. Co-occurrences of MAC and Legionella were detected in water and/or biofilms in all hot water systems at temperatures between 40 and 54 °C. Moderate correlations were observed between abundance of culturable MAC and that of MAC genome copies, and between MAC and total eubacterial genome copies. No quantitative relationship was observed between occurrence of Legionella and that of MAC. Persistence in hot water of live and dead M. avium cells and naked DNA was studied using PEX laboratory model systems at 44 °C. Naked DNA and DNA in dead M. avium cells persisted for weeks. Live M. avium increased tenfold in water and biofilms on PEX. The results suggest that water and biofilms in groundwater-based hot water systems can constitute reservoirs of MAC, and that amplifiable naked DNA is relatively short-lived, whereas PEX plumbing material supports persistence and proliferation of M. avium.

  20. Detection of Mycobacterium tuberculosis and Mycobacterium avium Complexes by Real-Time PCR in Bovine Milk from Brazilian Dairy Farms.

    PubMed

    Bezerra, André Vinícius Andrade; Dos Reis, Emily Marques; Rodrigues, Rogério Oliveira; Cenci, Alexander; Cerva, Cristine; Mayer, Fabiana Quoos

    2015-05-01

    Foodborne diseases are a public health problem worldwide. The consumption of contaminated raw milk has been recognized as a major cause of transmission of bovine tuberculosis to humans. Other mycobacteria that may be present in raw milk and may cause diseases are those belonging to the Mycobacterium avium complex. In this study, molecular biology tools were applied to investigate raw milk contamination with Mycobacterium spp. in family dairy farms from Rio Grande do Sul, southern Brazil. Furthermore, different variables related to the source of the milk, herd characteristics, and management were evaluated for their effect on milk contamination. Five hundred and two samples were analyzed, of which 354 were from the Northwest region (102 farms with samples from 93 bulk tanks and 261 animals) and 148 from the South region of the state (22 farms with samples from 23 bulk tanks and 125 animals). Among them, 10 (1.99%) and 7 (1.39%) were positive for Mycobacterium tuberculosis (9 confirmed as Mycobacterium bovis) and M. avium complexes, respectively. There was no difference in the frequencies of positive samples between the regions or the sample sources. Of the positive samples, 4 were collected from a bulk tank (1 positive for M. avium and 3 for M. tuberculosis). Moreover, 1 sample was positive concomitantly for M. tuberculosis and M. avium complexes. On risk analysis, no variable was associated with raw milk contamination by M. tuberculosis complex species. However, washing the udders of all animals and drying them with paper towels were weakly classified as risk factors for M. avium contamination. Positive samples were obtained from both animals and bulk tanks, which emphasizes the importance of tuberculosis control programs and provides evidence that milk monitoring can be used as a control practice. Moreover, the findings of this study reinforce the need for awareness of the problems of raw milk consumption among the general population.

  1. Clinical Evaluation of COBAS TaqMan PCR for the Detection of Mycobacterium tuberculosis and M. avium Complex

    PubMed Central

    Ikegame, Satoshi; Sakoda, Yoritake; Fujino, Nao; Taguchi, Kazuhito; Kawasaki, Masayuki; Kajiki, Akira

    2012-01-01

    A retrospective observational study was performed to determine the sensitivity and limitation of PCR test for the detection of Mycobacterium tuberculosis and M. avium complex. We obtained clinical specimens collected from the respiratory tract, cultured M. tuberculosis or M. avium complex, and performed PCR analysis. A total of 299 samples (M. tuberculosis, 177; M. avium, 35; M. intracellulare, 87) were analyzed by COBAS TaqMan PCR from April 2007 to March 2011. The PCR positivity rates were 50–55%, 70–100%, 88–98%, and 100% in smear-negative, smear 1+, 2+, and 3+ groups, respectively. The PCR positivity of tuberculosis in smear 1+ was 80.6%, which was statistically significantly (P < 0.001) lower than that of smear 2+ (97.3%). From January 2005 to March 2007, we collected an additional 138 samples (M. tuberculosis, 74; M. avium, 21; M. intracellulare, 43), which were analyzed by COBAS Amplicor PCR. The PCR positivity rates obtained using COBAS TaqMan PCR and COBAS Amplicor PCR were not significantly different. The sensitivity of PCR test for mycobacteria is not sufficient in case of smear 1+. Careful consideration must be given to the interpretation of negative PCR test results in smear 1+, because smear-positive tuberculosis is the criterion for isolation. PMID:23029612

  2. Disseminated Mycobacterium avium complex disease in a patient with left ventricular assist device (Heart Mate II).

    PubMed

    Cordioli, Maddalena; Del Bravo, Paola; Rigo, Fabio; Azzini, Anna Maria; Merighi, Mara; Forni, Alberto; Concia, Ercole

    2015-09-01

    Although disseminated Mycobacterium avium complex disease occurs mainly in immunocompromised hosts, especially HIV-infected patients in the last stage of the disease (AIDS), this condition is still rare in immunocompetent subjects. We report the case of a Caucasian man who received a left ventricular assist device two years before as a bridge to heart transplantation, that began to present signs and symptoms of mycobacterial infection. The diagnostic work-up we performed showed the presence of Mycobacterium intracellulare in lungs and both peripherical and bone marrow blood. Although evaluated, we found no abnormalities in the patient's immune system that can be related to mycobacterial infection. The beginning of a specific therapy made the patient slowly improve and further nuclear medicine assay (PET-TC) showed a good reduction in radio-labelled drug captation.

  3. Infection of Eurasian badgers (Meles meles) with Mycobacterium bovis and Mycobacterium avium complex in Spain.

    PubMed

    Balseiro, Ana; Rodríguez, Oscar; González-Quirós, Pablo; Merediz, Isabel; Sevilla, Iker A; Davé, Dipesh; Dalley, Deanna J; Lesellier, Sandrine; Chambers, Mark A; Bezos, Javier; Muñoz, Marta; Delahay, Richard J; Gortázar, Christian; Prieto, José M

    2011-11-01

    The prevalence, distribution and pathology related to infection with Mycobacterium bovis and other mycobacteria were determined in trapped (n=36) and road-killed (n=121) badgers in Spain from 2006 to 2010. The prevalence of M. bovis based on bacteriological culture from road-killed badgers was 8/121 (6.6%) and from trapped badgers was 0/36 (0%). Tuberculosis/M. bovis infection was evident in 15/121 (12.4%) road-killed badgers when bacteriology and histopathology were combined. Mycobacterium avium complex was isolated by culture from the tracheal aspirate of 1/36 (2.8%) trapped badgers and from tissue pools from 8/121 (6.6%) road-killed badgers.

  4. Mycobacterium avium Complex Osteomyelitis in Persons With Human Immunodeficiency Virus: Case Series and Literature Review

    PubMed Central

    Wood, Brian R.; Buitrago, Martha O.; Patel, Sugat; Hachey, David H.; Haneuse, Sebastien; Harrington, Robert D.

    2015-01-01

    In persons with advanced immunosuppression, Mycobacterium avium complex (MAC) typically causes disseminated disease with systemic symptoms. We report 2 cases in which MAC caused localized osteomyelitis in human immunodeficiency virus (HIV)-infected individuals on antiretroviral therapy with rising CD4 counts. We summarize 17 additional cases of HIV-associated MAC osteomyelitis from the literature and compare CD4 count at presentation for vertebral cases versus nonvertebral cases, which reveals a significantly higher CD4 at presentation for vertebral cases (median 251 cells/µL vs 50 cells/µL; P = .043; Mann–Whitney U test). The literature review demonstrates that the majority of cases of MAC osteomyelitis, especially vertebral, occurs in individuals with CD4 counts that have increased to above 100 cells/µL on antiretroviral therapy. Among HIV-infected individuals with osteomyelitis, MAC should be considered a possible etiology, particularly in the setting of immune reconstitution. PMID:26180837

  5. Rapid susceptibility testing of Mycobacterium avium complex and Mycobacterium tuberculosis isolated from AIDS patients

    NASA Technical Reports Server (NTRS)

    Dhople, Arvind M.

    1994-01-01

    In ominous projections issued by both U.S. Public Health Service and the World Health Organization, the epidemic of HIV infection will continue to rise more rapidly worldwide than predicted earlier. The AIDS patients are susceptible to diseases called opportunistic infections of which tuberculosis and Mycobacterium avium complex (MAC) infection are most common. This has created an urgent need to uncover new drugs for the treatment of these infections. In the seventies, NASA scientists at Goddard Space Flight Center, Greenbelt, MD, had adopted a biochemical indicator, adenosine triphosphate (ATP), to detect presence of life in extraterrestrial space. We proposed to develop ATP assay technique to determine sensitivity of antibacterial compounds against MAC and M. tuberculosis.

  6. Rapid drug susceptibility of Mycobacterium avium complex using a fluorescence quenching method.

    PubMed

    Marone, P; Bono, L; Carretto, E; Barbarini, D; Telecco, S

    1997-08-01

    Mycobacteria Growth Indicator Tube (MGIT) is a recently introduced rapid growth detection method which uses an oxygen quenched fluorescent indicator. The present study evaluated the ability of this new method to determine the drug susceptibility of Mycobacterium avium complex (MAC). Thirty strains recovered from patients with AIDS were tested for susceptibility to clarithromycin, rifabutin, ciprofloxacin, azithromycin and amikacin using MGIT. Results were compared to susceptibilities determined by the agar dilution method. The results obtained showed a 100% correlation between MGIT and the agar dilution method for rifabutin and clarithromycin. There was a 100% correlation between the two methods for azithromycin against 27 strains. MGIT was well correlated with the agar dilution method for detecting resistance to clarithromycin, rifabutin and azithromycin in 4 days, but the correlation was poor when susceptibilities to ciprofloxacin and amikacin were determined. This rapid method is non-radiometric, noninvasive and does not require any special instruments.

  7. Heat inactivation of Mycobacterium avium-Mycobacterium intracellulare complex organisms in meat products.

    PubMed Central

    Merkal, R S; Crawford, J A; Whipple, D L

    1979-01-01

    Wieners and sausages were prepared which contained the most heat-tolerant representative of the Mycobacterium avium-Mycobacterium intracellulare complex we were able to obtain. They also were prepared with infected tissues obtained from tuberculous swine. Processing conditions were as varied as possible. Neither incorporation of sodium nitrite in the emulsion nor presence of smoke during processing altered the heat susceptibility of the organisms. Substantial killing of the organisms occurred as wieners reached the upper processing temperatures, but hot oil or radiant heating of the "precooked" sausages allowed very short times within the killing range; hence, higher peak internal temperatures were necessary. The lethalities for these organisms of reaching and maintaining various processing temperatures are given. PMID:575610

  8. Comparative in vivo activities of rifabutin and rifapentine against Mycobacterium avium complex.

    PubMed Central

    Klemens, S P; Grossi, M A; Cynamon, M H

    1994-01-01

    The dose-response activity of rifabutin and the comparative activities of rifabutin and rifapentine were evaluated in the beige mouse model of disseminated Mycobacterium avium complex (MAC) infection. In the dose-response study, mice were infected intravenously with approximately 10(7) viable M. avium ATCC 49601. Treatment with rifabutin at 10, 20, or 40 mg/kg of body weight was started 7 days postinfection and was administered daily for 10 days. The mice were sacrificed 3 to 5 days after the last dose. Spleens, livers, and lungs were homogenized, and viable cell counts were determined by serial dilution and plating onto Middlebrook 7H10 agar. A dose-related reduction in MAC cell counts in the organs was noted for this MAC isolate. The comparative activities of rifabutin and rifapentine were determined against a total of five MAC isolates in the beige mouse model. Rifabutin or rifapentine (20 mg/kg each) was administered to infected mice for 10 days. Groups of treated mice were compared with untreated control animals. Despite favorable in vitro susceptibility results, rifabutin and rifapentine had activities in the spleens against only two of the five MAC isolates. For these two MAC isolates, rifabutin was more active than rifapentine. These agents had activities in the lungs against three of five isolates. Further study of rifabutin or rifapentine against a broader range of clinical isolates in a murine infection model may be useful as part of the continuing development of newer rifamycins as anti-MAC agents. PMID:8192449

  9. Mycobacterium avium complex suppurative parotitis in a patient with human immunodeficiency virus infection presenting with immune reconstitution inflammatory syndrome.

    PubMed

    Babiker, Zahir Osman Eltahir; Beeston, Christine; Purcell, Janet; Desai, Niranjan; Ustianowski, Andrew

    2010-11-01

    Restoration of the immune system following initiation of antiretroviral therapy can result in an adverse phenomenon known as immune reconstitution inflammatory syndrome (IRIS). Herein, we report a case of Mycobacterium avium complex (MAC) suppurative parotitis associated with IRIS in a patient with advanced human immunodeficiency virus disease. To the best of our knowledge, this is the first reported case of MAC parotitis in the setting of IRIS and clinicians should be aware of this condition.

  10. The clinical efficacy of a clarithromycin-based regimen for Mycobacterium avium complex disease: A nationwide post-marketing study.

    PubMed

    Kadota, Jun-Ichi; Kurashima, Atsuyuki; Suzuki, Katsuhiro

    2017-02-26

    The revised 2007 American Thoracic Society/Infectious Diseases Society of America statement recommend clarithromycin-based combination therapy for treatment of Mycobacterium avium complex lung disease and stipulates approximately 1 year of continuous treatment after bacilli negative conversion. However, supporting data are insufficient. Our objective was to obtain data on the clinical outcome of clarithromycin-based daily regimens by conducting a nationwide retrospective post-marketing study of M.avium complex lung disease. In accordance with the Japanese guidelines, patients were enrolled in this survey according to their chest radiographic findings and microbiologic test results. They were treated with a multidrug regimen including clarithromycin, rifampicin, and ethambutol (clarithromycin-based regimen) until bacilli negative conversion, and the treatment was continued for approximately 1 year after the initial conversion. Data were collected before administration, at the time of bacilli negative conversion, at the end of treatment, and at 6 months after the end of treatment. Of the 466 subjects enrolled in the study, 271 patients who received clarithromycin at 800 mg/day underwent evaluation for M.avium complex disease. The final bacilli negative conversion rate in those patients was 94.7%. The bacteriological relapse rate was 5.0% (5/100 patients). Bacteriological relapse was noted in patients treated for less than 15 months after conversion. No life-threatening or serious adverse drug reactions were observed. This study demonstrated that a clarithromycin-based daily regimen can yield a high bacteriological conversion rate in M.avium complex disease. After conversion, treatment for less than 15 months might be insufficient to prevent bacteriological relapse.

  11. The pncA gene from naturally pyrazinamide-resistant Mycobacterium avium encodes pyrazinamidase and confers pyrazinamide susceptibility to resistant M. tuberculosis complex organisms.

    PubMed

    Sun, Z; Scorpio, A; Zhang, Y

    1997-10-01

    The antituberculosis drug pyrazinamide (PZA) needs to be converted into pyrazinoic acid (POA) by the bacterial pyrazinamidase (PZase) in order to show bactericidal activity against Mycobacterium tuberculosis. M. avium is naturally resistant to PZA. To investigate whether this natural resistance to PZA is due to inability of the M. avium PZase to convert PZA to bactericidal POA, the M. avium PZase gene (pncA) was cloned by using the M. tuberculosis pncA gene as a probe. Sequence analysis showed that the M. avium pncA gene is 561 bp long, encoding a protein with a predicted size of about 19.8 kDa; but Western blotting showed that the M. avium PZase migrated as a 24 kDa band when expressed in M. bovis BCG and Escherichia coli. Sequence comparison revealed that M. avium PZase has 67.7% and 32.8% amino acid identity with the corresponding enzymes from M. tuberculosis and E. coli, respectively. Southern blot analysis with the M. avium pncA gene as a probe showed that M. terrae, M. gastri, M. marinum, M. fortuitum, M. xenopi, M. gordonae, M. szulgai, M. celatum and M. kansasii have close pncA homologues, whereas M. chelonae and M. smegmatis did not give significant hybridization signals. Transformation with the M. avium pncA gene conferred PZA susceptibility to PZA-resistant M. tuberculosis complex organisms, indicating that the nonsusceptibility of M. avium to PZA is not due to an ineffective PZase enzyme, but appears to be related to other factors such as transport of POA.

  12. Detection of Mycobacteria, Mycobacterium avium Subspecies, and Mycobacterium tuberculosis Complex by a Novel Tetraplex Real-Time PCR Assay

    PubMed Central

    Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M.

    2015-01-01

    Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses. PMID:25588660

  13. Detection of mycobacteria, Mycobacterium avium subspecies, and Mycobacterium tuberculosis complex by a novel tetraplex real-time PCR assay.

    PubMed

    Sevilla, Iker A; Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M; Juste, Ramón A

    2015-03-01

    Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses.

  14. Infection Sources of a Common Non-tuberculous Mycobacterial Pathogen, Mycobacterium avium Complex

    PubMed Central

    Nishiuchi, Yukiko; Iwamoto, Tomotada; Maruyama, Fumito

    2017-01-01

    Numerous studies have revealed a continuous increase in the worldwide incidence and prevalence of non-tuberculous mycobacteria (NTM) diseases, especially pulmonary Mycobacterium avium complex (MAC) diseases. Although it is not clear why NTM diseases have been increasing, one possibility is an increase of mycobacterial infection sources in the environment. Thus, in this review, we focused on the infection sources of pathogenic NTM, especially MAC. The environmental niches for MAC include water, soil, and dust. The formation of aerosols containing NTM arising from shower water, soil, and pool water implies that these niches can be infection sources. Furthermore, genotyping has shown that clinical isolates are identical to environmental ones from household tap water, bathrooms, potting soil, and garden soil. Therefore, to prevent and treat MAC diseases, it is essential to identify the infection sources for these organisms, because patients with these diseases often suffer from reinfections and recurrent infections with them. In the environmental sources, MAC and other NTM organisms can form biofilms, survive within amoebae, and exist in a free-living state. Mycobacterial communities are also likely to occur in these infection sources in households. Water distribution systems are a transmission route from natural water reservoirs to household tap water. Other infection sources include areas with frequent human contact, such as soil and bathrooms, indicating that individuals may carry NTM organisms that concomitantly attach to their household belongings. To explore the mechanisms associated with the global spread of infection and MAC transmission routes, an epidemiological population-wide genotyping survey would be very useful. A good example of the power of genotyping comes from M. avium subsp. hominissuis, where close genetic relatedness was found between isolates of it from European patients and pigs in Japan and Europe, implying global transmission of this bacterium

  15. Treatment of intracellular Mycobacterium avium complex infection by free and liposome-encapsulated sparfloxacin.

    PubMed Central

    Düzgüneş, N; Flasher, D; Reddy, M V; Luna-Herrera, J; Gangadharam, P R

    1996-01-01

    Mycobacterium avium-M. intracellulare complex (MAC) is the most frequent cause of opportunistic bacterial infection in patients with AIDS. Previous studies have indicated that liposome-encapsulated aminoglycosides are highly effective in treating MAC infections in mice. We investigated whether the fluoroquinolone sparfloxacin is effective in treating MAC infection in the murine macrophage-like cell line J774. Sparfloxacin was encapsulated in the membrane phase of multilamellar liposomes composed of phosphatidylglycerol-phosphatidylcholine-cholesterol (1:1:1 molar ratio). MAC-infected macrophages were treated for either 24 h or 4 days with free or liposome-encapsulated sparfloxacin. Treatment with free or liposome-encapsulated sparfloxacin (6 micrograms/ml) for 24 h resulted in the reduction of the growth index to 25 and 30% of that of untreated controls, respectively. When cultures were treated for 4 days, free sparfloxacin reduced the growth index to 6% of that of the untreated control, while liposome-encapsulated sparfloxacin reduced it to 8% of that of the control. PMID:8913475

  16. Mycobacterium avium complex--the role of potable water in disease transmission.

    PubMed

    Whiley, H; Keegan, A; Giglio, S; Bentham, R

    2012-08-01

    Mycobacterium avium complex (MAC) is a group of opportunistic pathogens of major public health concern. It is responsible for a wide spectrum of disease dependent on subspecies, route of infection and patients pre-existing conditions. Presently, there is limited research on the incidence of MAC infection that considers both pulmonary and other clinical manifestations. MAC has been isolated from various terrestrial and aquatic environments including natural waters, engineered water systems and soils. Identifying the specific environmental sources responsible for human infection is essential in minimizing disease prevalence. This paper reviews current literature and case studies regarding the wide spectrum of disease caused by MAC and the role of potable water in disease transmission. Potable water was recognized as a putative pathway for MAC infection. Contaminated potable water sources associated with human infection included warm water distribution systems, showers, faucets, household drinking water, swimming pools and hot tub spas. MAC can maintain long-term contamination of potable water sources through its high resistance to disinfectants, association with biofilms and intracellular parasitism of free-living protozoa. Further research is required to investigate the efficiency of water treatment processes against MAC and into construction and maintenance of warm water distribution systems and the role they play in MAC proliferation.

  17. Serodiagnosis of Mycobacterium avium complex disease in humans: translational research from basic mycobacteriology to clinical medicine.

    PubMed

    Kobayashi, Kazuo

    2014-01-01

    Rapid and accurate diagnosis of infectious diseases, including mycobacterial disease such as tuberculosis (TB) and diseases due to nontuberculous mycobacteria (NTM), is a very important element of global health. The gold standard in diagnosis of mycobacterial diseases remains clinical examination, combined with direct microscopic examination of sputum and culture of bacteria. Culture of slowly growing mycobacteria, including Mycobacterium tuberculosis and NTM (such as M. avium complex: MAC), can take up to 4 to 6 weeks, and in 10-20% of cases the bacillus is not successfully cultivated. Diagnosis of MAC pulmonary disease (MAC-PD) is complicated and time-consuming (usually at least 1 month). I have characterized the nature of MAC antigens and immune responses from the aspect of basic mycobacteriology, and then translated to clinical science. My multicenter study in Japan has demonstrated the usefulness of a serodiagnostic test to determine serum IgA antibodies against mycobacterial glycopeptidolipid (GPL) core antigen for diagnosing MAC-PD within a few hours. To validate in a larger number of patients, at diverse geographic locations, and among other races, the test was also assessed the usefulness internationally in the United States and Taiwan. In this review, I discuss development of serodiagnosis of MAC-PD by translational research and international collaboration study.

  18. Rapid susceptibility testing of mycobacterium avium complex and mycobacterium tuberculosis isolated from AIDS patients

    NASA Technical Reports Server (NTRS)

    Dhople, Arvind M.

    1993-01-01

    In ominous projections issued by both U.S. Public Health Service and the World Health Organization, the epidemic of the Human Immunodeficiency Virus (HIV) infection will continue to rise more rapidly worldwide than predicted earlier. The Acquired Immunodeficiency Syndrome (AIDS) patients are susceptible to diseases called opportunistic infections of which tuberculosis and M. avium Complex (MAC) infection are most common. This has created an urgent need to uncover new drugs for the treatment of these infections. In the seventies, NASA scientists at Goddard Space Flight Center, Greenbelt, Maryland, had adopted a biochemical indicator, adenosine triphosphate (ATP), to detect presence of life in extraterrestrial space. Therefore, we proposed to develop ATP assay technique to determine sensitivity of antibacterial compounds against MAC and M. tuberculosis. The work was initiated in June 1992. In the last report, we described our efforts in developing ATP assay method using MAC. Studies were continued further, and during the period of this report, we established the relationship between colony forming units and ATP levels of these organisms during the growth cycle. Also, we evaluated the effects of standard antimycobacterial drugs using ATP assay technique and compared the results with those obtained with conventional tube dilution proportional method.

  19. Isolation of Mycobacterium avium complex from bone marrow aspirates of AIDS patients in Brazil.

    PubMed

    Barreto, J A; Palaci, M; Ferrazoli, L; Martins, M C; Suleiman, J; Lorenço, R; Ferreira, O C; Riley, L W; Johnson, W D; Galvão, P A

    1993-09-01

    Mycobacterium avium complex (MAC) infection has not been reported as a major opportunistic infection among patients with AIDS in Latin America or Africa. In this study, 125 AIDS patients who had persistent fever, anemia, and leukopenia were examined among 2628 AIDS patients admitted to Instituto de Infectologia Emilio Ribas between May 1990 and April 1992. From the bone marrow aspirates of the 125 patients, MAC was isolated from 23 (18.4%) and Mycobacterium tuberculosis was isolated from 9 (7.2%). Between 1985 and 1990, only 11 MAC isolations among 60,000 cultures obtained from human immunodeficiency virus-seronegative patients were documented in São Paulo. Hence, the minimal estimated rate of MAC infection in AIDS patients in this city was 23/2628, or 0.88%. These findings suggest that MAC infection is an important opportunistic infection, especially among a subset of patients with AIDS in Brazil who have clinical characteristics and risk activities similar to those associated with MAC infections in North America and Europe.

  20. Peak Plasma Concentration of Azithromycin and Treatment Responses in Mycobacterium avium Complex Lung Disease.

    PubMed

    Jeong, Byeong-Ho; Jeon, Kyeongman; Park, Hye Yun; Moon, Seong Mi; Kim, Su-Young; Lee, Soo-Youn; Shin, Sung Jae; Daley, Charles L; Koh, Won-Jung

    2016-10-01

    Macrolides, such as azithromycin (AZM) and clarithromycin, are the cornerstones of treatment for Mycobacterium avium complex lung disease (MAC-LD). Current guidelines recommend daily therapy with AZM for cavitary MAC-LD and intermittent therapy for noncavitary MAC-LD, but the effectiveness of these regimens has not been thoroughly investigated. This study evaluated associations between microbiological response and estimated peak plasma concentrations (Cmax) of AZM. The AZM Cmax was measured in patients receiving daily therapy (250 mg of AZM daily, n = 77) or intermittent therapy (500 mg of AZM three times weekly, n = 89) for MAC-LD and daily therapy for Mycobacterium abscessus complex LD (MABC-LD) (250 mg of AZM daily, n = 55). The AZM Cmax was lower with the daily regimen for MAC-LD (median, 0.24 μg/ml) than with the intermittent regimen for MAC-LD (median, 0.65 μg/ml; P < 0.001) or daily therapy for MABC-LD (median, 0.53 μg/ml; P < 0.001). After adjusting for confounding factors, AZM Cmax was independently associated with favorable microbiological responses in MAC-LD patients receiving a daily regimen (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 1.01 to 2.48; P = 0.044) but not an intermittent regimen (aOR, 0.85; 95% CI, 0.58 to 1.23, P = 0.379). With the daily AZM-based multidrug regimen for MAC-LD, a low AZM Cmax was common, whereas a higher AZM Cmax was associated with favorable microbiologic responses. The results also suggested that the addition of rifampin may lower AZM Cmax When a daily AZM-based multidrug regimen is used for treating severe MAC-LD, such as cavitary disease, the currently recommended AZM dose might be suboptimal. (This study has been registered at ClinicalTrials.gov under identifier NCT00970801.).

  1. [A case of environmental infection with pulmonary Mycobacterium avium complex disease from a residential bathroom of a patient suggested by variable-number tandem-repeat typing of Mycobacterium avium tandem repeat loci].

    PubMed

    Taga, Shu; Niimi, Masaki; Kurokawa, Kazuhiro; Nakagawa, Taku; Ogawa, Kenji

    2012-05-01

    A 63-year-old woman was referred to our hospital because of bilateral infiltrations and nodular opacities in her chest radiograph taken in the mass radiography screening in September 2010. The chest computed tomography showed patchy infiltrations with bronchiectasis in the lower lung fields on both sides. She was diagnosed with pulmonary Mycobacterium avium complex (MAC) disease based on the bacteria recovered from the sputum and the bronchoalveolar lavage fluid. To elucidate an environmental MAC source, we investigated her home, and isolated M. avium and M. gordonae from the bathtub and shower tap, respectively, in her residential bathroom. Analysis of the hsp65-PRA variants digested with BamHI and some insertion sequences showed that the clinical strains recovered from sputum and strains from the bathtub were M. avium subsp. hominissuis. A dendrogram of the Mycobacterium avium tandem repeat loci variable-number tandem-repeat (MATR-VNTR) analysis of the MAC strains showed that the bathtub strains formed a polyclonal colonization, and that 1 of the 5 MATR-VNTR patterns was identical to the corresponding pattern of the sputum strain from the patient. In conclusion, we believe that the residential bathroom of the patient was the environmental source of her pulmonary MAC disease, as has been previously reported.

  2. Complexity: a potential paradigm for a health promotion discipline.

    PubMed

    Tremblay, Marie-Claude; Richard, Lucie

    2014-06-01

    Health promotion underpins a distancing from narrow, simplifying health approaches associated with the biomedical model. However, it has not yet succeeded in formally establishing its theoretical, epistemological and methodological foundations on a single paradigm. The complexity paradigm, which it has yet to broach head-on, might provide it with a disciplinary matrix in line with its implicit stances and basic values. This article seeks to establish complexity's relevance as a paradigm that can contribute to the development of a health promotion discipline. The relevance of complexity is justified primarily by its matching with several implicit epistemological and methodological/theoretical stances found in the cardinal concepts and principles of health promotion. The transcendence of ontological realism and determinism as well as receptiveness in respect of the reflexivity that complexity encompasses are congruent with the values of social justice, participation, empowerment and the concept of positive health that the field promotes. Moreover, from a methodological and theoretical standpoint, complexity assumes a holistic, contextual and transdisciplinary approach, toward which health promotion is tending through its emphasis on ecology and interdisciplinary action. In a quest to illustrate our position, developmental evaluation is presented as an example of practice stemming from a complexity paradigm that can be useful in the evaluation of health promotion initiatives. In short, we argue that it would be advantageous for health promotion to integrate this paradigm, which would provide it with a formal framework appropriate to its purposes and concerns.

  3. Relationship Between Lung Cancer and Mycobacterium Avium Complex Isolated Using Bronchoscopy

    PubMed Central

    Tamura, Atsuhisa; Hebisawa, Akira; Kusaka, Kei; Hirose, Takashi; Suzuki, Junko; Yamane, Akira; Nagai, Hideaki; Fukami, Takeshi; Ohta, Ken; Takahashi, Fumiaki

    2016-01-01

    Introduction: The incidence of Mycobacterium avium complex (MAC)-positive respiratory specimen cultures and MAC lung disease (MACLD) is increasing worldwide. This retrospective study aimed to assess the association between MAC culture-positive bronchoscopy specimens and lung cancer. Materials and Methods: The medical records of 1382 untreated lung cancer patients between 2003 and 2011 were collected using our hospital database. Of them, records for 1258 that had undergone bronchoscopy together with sampling for mycobacterial culture were reviewed. Patient characteristics were compared between those with MAC-positive/other nontuberculous mycobacteria (NTM)-negative bronchial washings and those with MAC-negative/other NTM-negative bronchial washings. Patients with MAC-positive lung cancer were cross-sectionally divided into MACLD and non-MACLD groups, and their features were assessed. Follow-up data for patients with lung cancer but without MACLD were reviewed for subsequent development of MACLD. Results: Of the 1258 patients with lung cancer, 25 (2.0%) had MAC-positive/other NTM-negative bronchial washings. The proportion of women (52% vs 30%; P = 0.0274) and patient age (72 years vs 69 years; P = 0.0380) were significantly higher in the MAC-positive/other NTM-negative lung cancer group (n = 25) than in the MAC-negative/other NTM-negative lung cancer group (n = 1223). There were 10 patients with lung cancer and MACLD and 15 without MACLD; significant differences in patient characteristics were not found between the two groups, and none of the 15 patients without MACLD subsequently developed MACLD. Conclusion: MAC culture-positive bronchial washing is positively associated with lung cancer. Female sex and advanced age, but not lung cancer characteristics, were found to be associated with MAC infection in patients with lung cancer. PMID:27335625

  4. THE EFFECT OF TEMPERATURE ON THE GROWTH OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS

    EPA Science Inventory

    MAC organisms are able to grow, persist, and colonize in water distribution systems and may amplify in hospital hot water systems. This study examined the response of MAC organisms (M. avium, M. intracellulare, and MX) to a range of temperatures commonly associated with drinking...

  5. Complex Engineered Systems: A New Paradigm

    NASA Astrophysics Data System (ADS)

    Mina, Ali A.; Braha, Dan; Bar-Yam, Yaneer

    Human history is often seen as an inexorable march towards greater complexity — in ideas, artifacts, social, political and economic systems, technology, and in the structure of life itself. While we do not have detailed knowledge of ancient times, it is reasonable to conclude that the average resident of New York City today faces a world of much greater complexity than the average denizen of Carthage or Tikal. A careful consideration of this change, however, suggests that most of it has occurred recently, and has been driven primarily by the emergence of technology as a force in human life. In the 4000 years separating the Indus Valley Civilization from 18th century Europe, human transportation evolved from the bullock cart to the hansom, and the methods of communication used by George Washington did not differ significantly from those used by Alexander or Rameses. The world has moved radically towards greater complexity in the last two centuries. We have moved from buggies and letter couriers to airplanes and the Internet — an increase in capacity, and through its diversity also in complexity, orders of magnitude greater than that accumulated through the rest of human history. In addition to creating iconic artifacts — the airplane, the car, the computer, the television, etc. — this change has had a profound effect on the scope of experience by creating massive, connected and multiultra- level systems — traffic networks, power grids, markets, multinational corporations — that defy analytical understanding and seem to have a life of their own. This is where complexity truly enters our lives.

  6. Isolation and identification of Mycobacterium avium complex and other nontuberculosis mycobacteria from drinking-water in Basra governorate, Iraq.

    PubMed

    Al-Sulami, A A; Al-Taee, A M R; Wida'a, Q H

    2012-03-01

    This study aimed to determine the occurrence of Mycobacterium avium complex and other nontuberculous mycobacteria in drinking-water in Basra governorate, Iraq and their susceptibility to several antibiotics and the effect of 0.5 mg/L of chlorine on their survival. A total of 404 samples of drinking-water were collected from 33 different districts of the governorate from November 2006 to August 2007. Filtered samples were incubated for 7 days or less in a monophasic-biphasic culture setup of tuberculosis broth and Lowenstein-Jensen agar. The 252 isolates were identified as M. avium complex (21), M. marinum (15), M. kansasii (30), M. simiae (20), M. szulgai (19), M. xenopi (16), M. malmoense (11), M. fortuitum (37), M. chelonae (50) and M. abscessus (33). Isolates were tested for antibiotic susceptibility as well as their ability to tolerate chlorine at a concentration of 0.5 mg/L. The presence of these pathogenic bacteria in drinking-water renders the water unfit for human consumption.

  7. [Identification of Mycobacterium avium-intracellulare complex by PCR of AIDS and disseminated mycobacteriosis].

    PubMed

    García-Elorriaga, Guadalupe; Degollado-Estrada, Edgar; Villagómez-Ruiz, Alfredo; Cortés-Torres, Nancy; Arreguín-Reséndiz, Lilián; Del Rey-Pineda, Guillermo; González-Bonilla, César

    2016-01-01

    Introducción: el objetivo de este artículo es Identificar y diferenciar el complejo MAC por PCR en pacientes con SIDA y micobacteriosis diseminada. Métodos: se llevó a cabo un estudio transversal para identificar MAC por biología molecular. Se sintetizaron dos conjuntos de iniciadores: MAV y MIN, para M. avium y M. intracellulare, respectivamente. El ADN total de células obtenidas de 29 aislados clínicos y muestras de suero de otros 24 pacientes con SIDA e infección micobacteriana diseminada fue extraído y se amplificó por PCR con los iniciadores MAV y MIN. Cada uno de los iniciadores MAV y MIN amplificó un segmento altamente específico de 1.3 kb del ADN homólogo, respectivamente. Resultados: veintinueve ADN de los aislados clínicos de MAC identificadas por Gen-Probe AccuProbes se amplificaron con los iniciadores MAV (M. avium). De las 24 muestras clínicas, 3 fueron positivas para M. avium y 6 para M. tuberculosis. Conclusiones: nuestros resultados demostraron que la técnica de PCR se puede aplicar para la diferenciación de M. avium y M. intracellulare por iniciadores específicos 16S rRNA. En pacientes con estadio avanzado de SIDA y en quienes se sospecha micobacteriosis diseminada, la presencia de anemia (incluso con cultivos negativos) fosfatasa alcalina elevada y una mediana de CD4 de 15.9/ml, se debe considerar seriamente el diagnóstico de infección por MAC; sugerimos que, de acuerdo con nuestros resultados, se justifica una estratificación más precisa de los pacientes en términos de sus recuentos de células T CD4.

  8. Preliminary Evaluation of a Sitafloxacin-Containing Regimen for Relapsed or Refractory Pulmonary Mycobacterium avium Complex Disease

    PubMed Central

    Fujita, Kohei; Fujita, Masaki; Ito, Yutaka; Hirai, Toyohiro; Mio, Tadashi; Watanabe, Kentaro; Mishima, Michiaki

    2016-01-01

    Although sitafloxacin (STFX) is known to have a favorable minimum inhibitory concentration for Mycobacterium avium, few studies have evaluated the clinical efficacy of an STFX-containing regimen for pulmonary M avium complex (MAC) disease. To evaluate the clinical efficacy of STFX-containing regimens for relapsed or refractory pulmonary MAC disease, we retrospectively reviewed 18 patients with pulmonary MAC disease who received STFX for at least 4 weeks for pulmonary MAC disease between January 2008 and February 2016. Of 18 patients, 10 (55.6%) showed improved radiological characteristics and 8 (44.4%) showed negative sputum cultures at 6 months. Regarding the clinical symptoms, improvements were observed in decreasing order in sputum production (77.8%), cough (72.2%), and malaise (55.6%). Common adverse events included nausea or vomiting (38.9%), followed by loose stool or diarrhea (27.8%) and sleepiness (11.1%). Although this study contained a small number of subjects, we describe a STFX-containing regimen that was effective in achieving sputum culture negative conversions and had an acceptable adverse events profile. PMID:27704005

  9. Clinical and epidemiological correlates of genotypes within the Mycobacterium avium complex defined by restriction and sequence analysis of hsp65.

    PubMed

    Smole, Sandra C; McAleese, Fionnuala; Ngampasutadol, Jutamas; Von Reyn, C Fordham; Arbeit, Robert D

    2002-09-01

    Species identification of isolates of the Mycobacterium avium complex (MAC) remains a difficult task. Although M. avium and Mycobacterium intracellulare can be identified with expensive, commercially available probes, many MAC isolates remain unresolved, including those representing Mycobacterium lentiflavum as well as other potentially undefined species. PCR restriction analysis (PRA) of the hsp65 gene has been proposed as a rapid and inexpensive approach. We applied PRA to 278 MAC isolates, including 126 from blood of human immunodeficiency virus (HIV)-infected patients, 59 from sputum of HIV-negative patients with chronic obstructive pulmonary disease, 88 from environmental sources, and 5 pulmonary isolates from a different study. A total of 15 different PRA patterns were observed. For 27 representative isolates, a 441-bp fragment of the hsp65 gene was sequenced; based on 54 polymorphic sites, 18 different alleles were defined, including 12 alleles not previously reported. Species and phylogenetic relationships were more accurately defined by sequencing than by PRA or commercial probe. The distribution of PRA types and, by implication, phylogenetic lineages among blood isolates was significantly different from that for pulmonary and environmental isolates, suggesting that particular lineages have appreciably greater virulence and invasive potential.

  10. Broncho-Pleural Fistula with Hydropneumothorax at CT: Diagnostic Implications in Mycobacterium avium Complex Lung Disease with Pleural Involvement

    PubMed Central

    Yoon, Hyun Jung; Chung, Myung Jin; Lee, Kyung Soo; Kim, Jung Soo; Park, Hye Yun

    2016-01-01

    Objective To determine the patho-mechanism of pleural effusion or hydropneumothorax in Mycobacterium avium complex (MAC) lung disease through the computed tomographic (CT) findings. Materials and Methods We retrospectively collected data from 5 patients who had pleural fluid samples that were culture-positive for MAC between January 2001 and December 2013. The clinical findings were investigated and the radiological findings on chest CT were reviewed by 2 radiologists. Results The 5 patients were all male with a median age of 77 and all had underlying comorbid conditions. Pleural fluid analysis revealed a wide range of white blood cell counts (410–100690/µL). The causative microorganisms were determined as Mycobacterium avium and Mycobacterium intracellulare in 1 and 4 patients, respectively. Radiologically, the peripheral portion of the involved lung demonstrated fibro-bullous changes or cavitary lesions causing lung destruction, reflecting the chronic, insidious nature of MAC lung disease. All patients had broncho-pleural fistulas (BPFs) and pneumothorax was accompanied with pleural effusion. Conclusion In patients with underlying MAC lung disease who present with pleural effusion, the presence of BPFs and pleural air on CT imaging are indicative that spread of MAC infection is the cause of the effusion. PMID:26957917

  11. [The dimension of the paradigm of complexity in health systems].

    PubMed

    Fajardo-Ortiz, Guillermo; Fernández-Ortega, Miguel Ángel; Ortiz-Montalvo, Armando; Olivares-Santos, Roberto Antonio

    2015-01-01

    This article presents elements to better understand health systems from the complety paradigm, innovative perspective that offers other ways in the conception of the scientific knowledge prevalent away from linear, characterized by the arise of emerging dissociative and behaviors, based on the intra and trans-disciplinarity concepts such knowledges explain and understand in a different way what happens in the health systems with a view to efficiency and effectiveness. The complexity paradigm means another way of conceptualizing the knowledge, is different from the prevalent epistemology, is still under construction does not separate, not isolated, is not reductionist, or fixed, does not solve the problems, but gives other bases to know them and study them, is a different strategy, a perspective that has basis in the systems theory, informatics and cybernetics beyond traditional knowledge, the positive logics, the newtonian physics and symmetric mathematics, in which everything is centered and balanced, joint the "soft sciences and hard sciences", it has present the Social Determinants of Health and organizational culture. Under the complexity paradigm the health systems are identified with the following concepts: entropy, neguentropy, the thermodynamic second law, attractors, chaos theory, fractals, selfmanagement and self-organization, emerging behaviors, percolation, uncertainty, networks and robusteness; such expressions open new possibilities to improve the management and better understanding of the health systems, giving rise to consider health systems as complex adaptive systems.

  12. The presence of opportunistic pathogens, Legionella spp., L. pneumophila and Mycobacterium avium complex, in South Australian reuse water distribution pipelines.

    PubMed

    Whiley, H; Keegan, A; Fallowfield, H; Bentham, R

    2015-06-01

    Water reuse has become increasingly important for sustainable water management. Currently, its application is primarily constrained by the potential health risks. Presently there is limited knowledge regarding the presence and fate of opportunistic pathogens along reuse water distribution pipelines. In this study opportunistic human pathogens Legionella spp., L. pneumophila and Mycobacterium avium complex were detected using real-time polymerase chain reaction along two South Australian reuse water distribution pipelines at maximum concentrations of 10⁵, 10³ and 10⁵ copies/mL, respectively. During the summer period of sampling the concentration of all three organisms significantly increased (P < 0.05) along the pipeline, suggesting multiplication and hence viability. No seasonality in the decrease in chlorine residual along the pipelines was observed. This suggests that the combination of reduced chlorine residual and increased water temperature promoted the presence of these opportunistic pathogens.

  13. Evaluation of a high-throughput repetitive-sequence-based PCR system for DNA fingerprinting of Mycobacterium tuberculosis and Mycobacterium avium complex strains.

    PubMed

    Cangelosi, Gerard A; Freeman, Robert J; Lewis, Kaeryn N; Livingston-Rosanoff, Devon; Shah, Ketan S; Milan, Sparrow Joy; Goldberg, Stefan V

    2004-06-01

    Repetitive-sequence-based PCR (rep-PCR) is useful for generating DNA fingerprints of diverse bacterial and fungal species. Rep-PCR amplicon fingerprints represent genomic segments lying between repetitive sequences. A commercial system that electrophoretically separates rep-PCR amplicons on microfluidic chips, and provides computer-generated readouts of results has been adapted for use with Mycobacterium species. The ability of this system to type M. tuberculosis and M. avium complex (MAC) isolates was evaluated. M. tuberculosis strains (n = 56) were typed by spoligotyping with rep-PCR as a high-resolution adjunct. Results were compared with those generated by a standard approach of spoligotyping with IS6110-targeted restriction fragment length polymorphism (IS6110-RFLP) as the high-resolution adjunct. The sample included 11 epidemiologically and genotypically linked outbreak isolates and a population-based sample of 45 isolates from recent immigrants to Seattle, Wash., from the African Horn countries of Somalia, Eritrea, and Ethiopia. Twenty isolates exhibited unique spoligotypes and were not analyzed further. Of the 36 outbreak and African Horn isolates with nonunique spoligotypes, 23 fell into four clusters identified by IS6110-RFLP and rep-PCR, with 97% concordance observed between the two methods. Both approaches revealed extensive strain heterogeneity within the African Horn sample, consistent with a predominant pattern of reactivation of latent infections in this immigrant population. Rep-PCR exhibited 89% concordance with IS1245-RFLP typing of 28 M. avium subspecies avium strains. For M. tuberculosis as well as M. avium subspecies avium, the discriminative power of rep-PCR equaled or exceeded that of RFLP. Rep-PCR also generated DNA fingerprints from M. intracellulare (n = 8) and MAC(x) (n = 2) strains. It shows promise as a fast, unified method for high-throughput genotypic fingerprinting of multiple Mycobacterium species.

  14. Absence of Mycobacterium intracellulare and Presence of Mycobacterium chimaera in Household Water and Biofilm Samples of Patients in the United States with Mycobacterium avium Complex Respiratory Disease

    PubMed Central

    Iakhiaeva, Elena; Williams, Myra D.; Brown-Elliott, Barbara A.; Vasireddy, Sruthi; Vasireddy, Ravikiran; Lande, Leah; Peterson, Donald D.; Sawicki, Janet; Kwait, Rebecca; Tichenor, Wellington S.; Turenne, Christine; Falkinham, Joseph O.

    2013-01-01

    Recent studies have shown that respiratory isolates from pulmonary disease patients and household water/biofilm isolates of Mycobacterium avium could be matched by DNA fingerprinting. To determine if this is true for Mycobacterium intracellulare, household water sources for 36 patients with Mycobacterium avium complex (MAC) lung disease were evaluated. MAC household water isolates from three published studies that included 37 additional MAC respiratory disease patients were also evaluated. Species identification was done initially using nonsequencing methods with confirmation by internal transcribed spacer (ITS) and/or partial 16S rRNA gene sequencing. M. intracellulare was identified by nonsequencing methods in 54 respiratory cultures and 41 household water/biofilm samples. By ITS sequencing, 49 (90.7%) respiratory isolates were M. intracellulare and 4 (7.4%) were Mycobacterium chimaera. In contrast, 30 (73%) household water samples were M. chimaera, 8 (20%) were other MAC X species (i.e., isolates positive with a MAC probe but negative with species-specific M. avium and M. intracellulare probes), and 3 (7%) were M. avium; none were M. intracellulare. In comparison, M. avium was recovered from 141 water/biofilm samples. These results indicate that M. intracellulare lung disease in the United States is acquired from environmental sources other than household water. Nonsequencing methods for identification of nontuberculous mycobacteria (including those of the MAC) might fail to distinguish closely related species (such as M. intracellulare and M. chimaera). This is the first report of M. chimaera recovery from household water. The study underscores the importance of taxonomy and distinguishing the many species and subspecies of the MAC. PMID:23536397

  15. Absence of Mycobacterium intracellulare and presence of Mycobacterium chimaera in household water and biofilm samples of patients in the United States with Mycobacterium avium complex respiratory disease.

    PubMed

    Wallace, Richard J; Iakhiaeva, Elena; Williams, Myra D; Brown-Elliott, Barbara A; Vasireddy, Sruthi; Vasireddy, Ravikiran; Lande, Leah; Peterson, Donald D; Sawicki, Janet; Kwait, Rebecca; Tichenor, Wellington S; Turenne, Christine; Falkinham, Joseph O

    2013-06-01

    Recent studies have shown that respiratory isolates from pulmonary disease patients and household water/biofilm isolates of Mycobacterium avium could be matched by DNA fingerprinting. To determine if this is true for Mycobacterium intracellulare, household water sources for 36 patients with Mycobacterium avium complex (MAC) lung disease were evaluated. MAC household water isolates from three published studies that included 37 additional MAC respiratory disease patients were also evaluated. Species identification was done initially using nonsequencing methods with confirmation by internal transcribed spacer (ITS) and/or partial 16S rRNA gene sequencing. M. intracellulare was identified by nonsequencing methods in 54 respiratory cultures and 41 household water/biofilm samples. By ITS sequencing, 49 (90.7%) respiratory isolates were M. intracellulare and 4 (7.4%) were Mycobacterium chimaera. In contrast, 30 (73%) household water samples were M. chimaera, 8 (20%) were other MAC X species (i.e., isolates positive with a MAC probe but negative with species-specific M. avium and M. intracellulare probes), and 3 (7%) were M. avium; none were M. intracellulare. In comparison, M. avium was recovered from 141 water/biofilm samples. These results indicate that M. intracellulare lung disease in the United States is acquired from environmental sources other than household water. Nonsequencing methods for identification of nontuberculous mycobacteria (including those of the MAC) might fail to distinguish closely related species (such as M. intracellulare and M. chimaera). This is the first report of M. chimaera recovery from household water. The study underscores the importance of taxonomy and distinguishing the many species and subspecies of the MAC.

  16. Bordetella avium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bordetellosis is an acute, highly contagious disease of the upper respiratory tract of young turkeys (4-8 wk of age). The disease is caused by a gram-negative, nonfermentative bacterium, Bordetella avium. Members of the genus Bordetella are well known for their ability to colonize and damage ciliate...

  17. [Nursing education in the light of the complexity paradigm].

    PubMed

    da Silva, Ana Lúcia; Camillo, Simone de Oliveira

    2007-09-01

    The objectives of this research were to recognize, interpret and discuss themes that arise out of the speeches of instructors of an undergraduate course of Nursing as guiding sources to a humanized teaching-learning experience in the light of Edgard Morin's Theory of Complexity. It is a qualitative, exploratory and analytic research. The study tried to verify principles of the paradigm of complexity through content analysis, theme modality, in the speeches of 11 instructors, obtained in 2004. The themes that were found were: teaching the instructor's responsibility; combining knowledge: connections and interrelations to face reality; teaching human complexity; stimulating creativity and curiosity; facing uncertainty: building life's continuous, dynamic knowledge; experiencing the teaching-learning process through transdisciplinarity; and teaching citizenship. This study shows that it is possible to have a university education based on the human condition, solidarity and knowledge interconnection.

  18. Clarithromycin Susceptibility Testing of Mycobacterium avium Complex Using 2,3-Diphenyl-5-thienyl-(2)-tetrazolium Chloride Microplate Assay with Middlebrook 7H9 Broth

    PubMed Central

    Park, Young Kil; Koh, Won-Jung; Kim, Shin Ok; Shin, Sonya; Kim, Bum Joon; Cho, Sang-Nae; Lee, Sun Min

    2009-01-01

    A series of 119 Mycobacterium avium complex isolates were subjected to clarithromycin susceptibility testing using microplates containing 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC). Among 119 isolates, 114 (95.8%) were susceptible to clarithromycin and 5 were resistant according to the new and the standard method. STC counts the low cost and reduces the number of procedures needed for susceptibility testing. PMID:19543518

  19. Characterization and growth in human macrophages of Mycobacterium avium complex strains isolated from the blood of patients with acquired immunodeficiency syndrome.

    PubMed Central

    Meylan, P R; Richman, D D; Kornbluth, R S

    1990-01-01

    Strains of the Mycobacterium avium complex (MAC) yield opaque and transparent colonial variants when cultivated in vitro. The transparent variants are more virulent than the opaque for animals, but little is known about the respective roles of these colonial variants in humans. To assess which variant infects humans, various blood fractions from eight patients with MAC bacteremia were plated directly onto 7H10 agar. In cell fractionation studies, all the M. avium complex CFU were associated with leukocytes and none were found free in plasma. All colonies on the primary culture plate exhibited the transparent phenotype. However, during subculture in 7H9 broth or on Lowenstein-Jensen agar, opaque variants appeared in seven of eight strains. Isogenic pairs of transparent and opaque variants were prepared and used to infect in vitro human monocyte-derived macrophages from healthy seronegative individuals. Transparent variants invariably grew inside macrophages, but only one of seven opaque variants did so. These observations indicate that the bacteremia of M. avium complex in acquired immunodeficiency syndrome patients consists exclusively of the transparent variants, perhaps because these variants are able to multiply inside macrophages. In contrast, opaque variants appear after in vitro subculture and are controlled by human macrophages, consistent with their reduced virulence in animals. Images PMID:2370109

  20. Early bactericidal activity of rifabutin versus that of placebo in treatment of disseminated Mycobacterium avium complex bacteremia in AIDS patients.

    PubMed Central

    Dautzenberg, B; Castellani, P; Pellegrin, J L; Vittecoq, D; Truffot-Pernot, C; Pirotta, N; Sassella, D

    1996-01-01

    Rifabutin, 600 mg/day, was compared with a placebo in the early treatment of culture-proven Mycobacterium avium bacteremia in patients with AIDS. Following 14 days' treatment, bacteriological success, defined as a negative culture or a reduction in the number of CFU of M. avium organisms per milliliter of blood by a factor of > or = 0.5 log from the baseline, was observed in 7 of 10 (70%) evaluable rifabutin patients and in 1 of 13 (8%) evaluable placebo patients (P = 0.002). Rifabutin is active against M. avium as a single agent and can make a significant contribution to combination regimens for the treatment of disseminated M. avium infection in AIDS patients. PMID:8807071

  1. Loop-Mediated Isothermal Amplification for Direct Detection of Mycobacterium tuberculosis Complex, M. avium, and M. intracellulare in Sputum Samples

    PubMed Central

    Iwamoto, Tomotada; Sonobe, Toshiaki; Hayashi, Kozaburo

    2003-01-01

    Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method in which reagents react under isothermal conditions with high specificity, efficiency, and rapidity. We used LAMP for detection of Mycobacterium tuberculosis complex, Mycobacterium avium, and Mycobacterium intracellulare directly from sputum specimens as well as for detection of culture isolates grown in a liquid medium (MGIT; Nippon Becton Dickinson Co., Ltd., Tokyo, Japan) or on a solid medium (Ogawa's medium). Species-specific primers were designed by targeting the gyrB gene, and their specificities were validated on 24 mycobacterial species and 7 nonmycobacterial species. The whole procedure is quite simple, starting with the mixing of all reagents in a single tube, followed by an isothermal reaction during which the reaction mixture is held at 63°C. The resulting amplicons are visualized by adding SYBR Green I to the reaction tube. The only equipment needed for the amplification reaction is a regular laboratory water bath or heat block that furnishes a constant temperature of 63°C. The assay had a detection limit of 5 to 50 copies of purified DNA with a 60-min incubation time. The reaction time could be shortened to 35 min for the species identification of M. tuberculosis complex, M. avium, and M. intracellulare from a solid-medium culture. Residual DNA lysates prepared for the Amplicor assay (Roche Diagnostics GmbH) from 66 sputum specimens were tested in the LAMP assay. Although the sample size used for the latter assay was small, 2.75 μl of the DNA lysates, it showed a performance comparable with that of the Amplicor assay, which required 50 μl of the lysates. This LAMP-based assay is simple, rapid, and sensitive; a result is available in 35 min for a solid-medium culture and in 60 min for a liquid-medium culture or for a sputum specimen that contains a corresponding amount of DNA available for testing. PMID:12791888

  2. Azithromycin, rifabutin, and rifapentine for treatment and prophylaxis of Mycobacterium avium complex in rats treated with cyclosporine.

    PubMed Central

    Brown, S T; Edwards, F F; Bernard, E M; Tong, W; Armstrong, D

    1993-01-01

    Azithromycin, rifabutin, and rifapentine were used to treat or prevent disseminated Mycobacterium avium complex (MAC) infections produced in rats immunosuppressed with cyclosporine. Animals with bacteremic infections were treated 1 week after intravenous inoculation with 10(7) CFU of MAC with azithromycin, 100 mg/kg of body weight administered subcutaneously for 5 days and then 75 mg/kg on Monday, Wednesday, and Friday, or with rifabutin or rifapentine, 20 mg/kg administered intraperitoneally on Monday through Friday. All three drugs showed efficacy after 1 and 2 months. Rifabutin cleared the organisms from tissues more rapidly than azithromycin or rifapentine. To approximate prophylaxis, treatment was started 2 weeks before intravenous inoculation with 10(4) organisms. MAC infections were undetectable in treated animals after 4 months, while control animals had disseminated infections. These findings support the rationale for clinical trials of treatment and prophylaxis with these agents. The cyclosporine-treated rat appears to be a useful model in which to evaluate compounds for the treatment and prophylaxis of disseminated MAC infections. PMID:8384809

  3. Beyond the oncogene paradigm: understanding complexity in cancerogenesis.

    PubMed

    Bizzarri, M; Cucina, A; Conti, F; D'Anselmi, F

    2008-09-01

    In the past decades, an enormous amount of precious information has been collected about molecular and genetic characteristics of cancer. This knowledge is mainly based on a reductionistic approach, meanwhile cancer is widely recognized to be a 'system biology disease'. The behavior of complex physiological processes cannot be understood simply by knowing how the parts work in isolation. There is not solely a matter how to integrate all available knowledge in such a way that we can still deal with complexity, but we must be aware that a deeply transformation of the currently accepted oncologic paradigm is urgently needed. We have to think in terms of biological networks: understanding of complex functions may in fact be impossible without taking into consideration influences (rules and constraints) outside of the genome. Systems Biology involves connecting experimental unsupervised multivariate data to mathematical and computational approach than can simulate biologic systems for hypothesis testing or that can account for what it is not known from high-throughput data sets. Metabolomics could establish the requested link between genotype and phenotype, providing informations that ensure an integrated understanding of pathogenic mechanisms and metabolic phenotypes and provide a screening tool for new targeted drug.

  4. Evaluation of the MycoAKT latex agglutination test for rapid diagnosis of Mycobacterium avium complex infections.

    PubMed

    Olano, J P; Holmes, H; Woods, G L

    1998-01-01

    Rapid diagnosis of Mycobacterium avium complex (MAC) bacteremia is important for management of patients with the acquired immunodeficiency syndrome who have disseminated MAC. The purpose of this study was to determine the reliability of the MycoAKT latex agglutination test for direct detection of MAC in positive mycobacterial blood cultures. First, colonies of isolates of previously identified mycobacteria, including 35 MAC, were tested. Of the 55 isolates evaluated, 33 were identified as MAC by the latex test, including 31 of the known MAC and 2 M. chelonae (sensitivity, 88.6%; specificity, 90.0%). Second, broth from 20 ESP II and 20 BACTEC 12B bottles seeded with isolates of MAC were tested. Aliquots from 19 (95%) ESP II cultures and 16 (80%) 12B cultures were positive by the latex test. In phase 3, broth from 115 signal-positive ESP II blood cultures were tested by latex agglutination. Forty-three subcultures from these bottles grew mycobacteria (41 MAC and 2 Mycobacterium tuberculosis complex); the remainder grew no organisms. Broth from 40 of the blood cultures (39 that grew MAC and 1 from which no organisms were recovered) were latex positive; thus, the sensitivity, specificity, and positive and negative predictive values of the latex test for direct identification of MAC in ESP II blood cultures were 95.1, 98.6, 97.5, and 97.3%, respectively. The mean time to detection of MAC was 14.6 days (range, 6-34 days) with the direct latex test, compared with 18.3 days (range, 9-36 days) with subculture and probe (p < 0.05).

  5. Distribution of Mycobacterium avium Complex Isolates in Tissue Samples of Pigs Fed Peat Naturally Contaminated with Mycobacteria as a Supplement

    PubMed Central

    Matlova, Ludmila; Dvorska, Lenka; Ayele, Wuhib Yayo; Bartos, Milan; Amemori, Takashi; Pavlik, Ivo

    2005-01-01

    In early 1999, there was an increased incidence of tuberculous lesions in the lymph nodes of slaughtered pigs in the Czech Republic. In part 1 of this study, tuberculous lesions were detected in 140 (62%) tissue samples collected from pigs coming from 15 farms in 15 districts at routine veterinary meat inspections in abattoirs. Mycobacteria were isolated from 37 (16%) tissue samples: 34 Mycobacterium avium subsp. hominissuis isolates and three environmentally derived mycobacteria. In search of infection sources, M. avium subsp. hominissuis was isolated from 38 (79%) samples of peat used as a feed supplement. In part 2 of our study, the head, mesenteric, and inguinal lymph nodes of 117 randomly selected slaughtered pigs from one farm with young piglets fed peat as a supplement were investigated for mycobacterial infection. From 65 (56%) pigs, a total of 76 mycobacterial isolates were identified (56 M. avium subsp. hominissuis isolates, 5 M. avium subsp. avium isolates, 3 M. intracellulare isolates, and 12 environmentally derived mycobacterial isolates). IS1245 restriction fragment length polymorphism (RFLP) types with >20 bands of 45 distinct RFLP types were found in 49 M. avium subsp. hominissuis isolates from pigs (n = 31) and peat (n = 18). Identical RFLP types were found in only four pig isolates. Five randomly selected isolates from pigs and peat were subcultured to six independent clones or colonies. Among the IS1245 RFLP types of 30 clones, identical RFLP types obtained from pigs and peat were identified, which confirmed the hypothesis that peat contaminated with mycobacteria represents a significant source of mycobacterial infection for pigs. PMID:15750094

  6. Clinical Characteristics, Treatment Outcomes, and Resistance Mutations Associated with Macrolide-Resistant Mycobacterium avium Complex Lung Disease.

    PubMed

    Moon, Seong Mi; Park, Hye Yun; Kim, Su-Young; Jhun, Byung Woo; Lee, Hyun; Jeon, Kyeongman; Kim, Dae Hun; Huh, Hee Jae; Ki, Chang-Seok; Lee, Nam Yong; Kim, Hong Kwan; Choi, Yong Soo; Kim, Jhingook; Lee, Seung-Heon; Kim, Chang Ki; Shin, Sung Jae; Daley, Charles L; Koh, Won-Jung

    2016-11-01

    Macrolide antibiotics are key components of the multidrug treatment regimen for treating lung disease (LD) due to Mycobacterium avium complex (MAC). Despite the emergence of macrolide resistance, limited data are available on macrolide-resistant MAC-LD. This study evaluated the clinical features and treatment outcomes of patients with macrolide-resistant MAC-LD and the molecular characteristics of the macrolide-resistant isolates. A retrospective review of the medical records of 34 patients with macrolide-resistant MAC-LD who were diagnosed between January 2002 and December 2014 was performed, along with genetic analysis of 28 clinical isolates. Nineteen (56%) patients had the fibrocavitary form of MAC-LD, and 15 (44%) had the nodular bronchiectatic form. M. intracellulare was the etiologic organism in 21 (62%) patients. Approximately two-thirds (22/34 [65%]) of the patients had been treated with currently recommended multidrug regimens that included macrolide, ethambutol, and rifamycin prior to the emergence of macrolide resistance, and none had been treated with macrolide monotherapy. The median duration of treatment after the detection of macrolide resistance was 23.0 months (interquartile range, 16.8 to 45.3 months). Treatment outcomes were poor after the development of macrolide resistance, with favorable treatment outcomes achieved in only five (15%) patients, including two patients who underwent surgical resection. One-, 3-, and 5-year mortality rates were 9, 24, and 47%, respectively. Molecular analysis of 28 clinical isolates revealed that 96% (27/28) had point mutations at position 2058 or 2059 of the 23S rRNA gene. Our analyses indicate that more effective therapy is needed to treat macrolide-resistant MAC-LD and prevent its development.

  7. Activities of sparfloxacin, azithromycin, temafloxacin, and rifapentine compared with that of clarithromycin against multiplication of Mycobacterium avium complex within human macrophages.

    PubMed Central

    Perronne, C; Gikas, A; Truffot-Pernot, C; Grosset, J; Vilde, J L; Pocidalo, J J

    1991-01-01

    The activities of sparfloxacin, azithromycin, temafloxacin, and rifapentine against two virulent strains of the Mycobacterium avium complex isolated from patients with AIDS were evaluated in a model of intracellular infection and were compared with that of clarithromycin. Human monocyte-derived macrophages were infected with the M. avium complex at day 6 of culture. The intracellular CFU was counted 60 min after inoculation. The intracellular and supernatant CFU was counted on days 4 and 7 after inoculation. The concentrations used, which were equal to peak levels in serum, were 10 micrograms of rifapentine per ml (MICs for the two strains, 4 and 16 micrograms/ml), 4 micrograms of clarithromycin per ml (MICs, 8 and 4 micrograms/ml), 1 microgram of azithromycin per ml (MICs, 32 and 16 micrograms/ml), 4 micrograms of temafloxacin per ml (MICs, 2 and 16 micrograms/ml), and 1 microgram of sparfloxacin per ml (MICs, 0.5 and 2 micrograms/ml). Compared with controls on day 7 after inoculation, clarithromycin (P less than 0.001), sparfloxacin (P less than 0.001), and azithromycin (P less than 0.001 for the first strain, P less than 0.02 for the second) slowed intracellular replication. Rifapentine (P less than 0.001) and temafloxacin (P less than 0.001) slowed intracellular replication of the first strain but not of the second strain. Azithromycin plus sparfloxacin was as effective as sparfloxacin alone. In this macrophage model, sparfloxacin or clarithromycin (difference not significant) exhibited a better efficacy than rifapentine, azithromycin, or temafloxacin against intracellular M. avium complex infection. PMID:1656860

  8. Virulence and Immune Response Induced by Mycobacterium avium Complex Strains in a Model of Progressive Pulmonary Tuberculosis and Subcutaneous Infection in BALB/c Mice

    PubMed Central

    González-Pérez, Mónica; Mariño-Ramírez, Leonardo; Parra-López, Carlos Alberto; Murcia, Martha Isabel; Marquina, Brenda; Mata-Espinoza, Dulce; Rodriguez-Míguez, Yadira; Baay-Guzman, Guillermina J.; Huerta-Yepez, Sara

    2013-01-01

    The genus Mycobacterium comprises more than 150 species, including important pathogens for humans which cause major public health problems. The vast majority of efforts to understand the genus have been addressed in studies with Mycobacterium tuberculosis. The biological differentiation between M. tuberculosis and nontuberculous mycobacteria (NTM) is important because there are distinctions in the sources of infection, treatments, and the course of disease. Likewise, the importance of studying NTM is not only due to its clinical significance but also due to the mechanisms by which some species are pathogenic while others are not. Mycobacterium avium complex (MAC) is the most important group of NTM opportunistic pathogens, since it is the second largest medical complex in the genus after the M. tuberculosis complex. Here, we evaluated the virulence and immune response of M. avium subsp. avium and Mycobacterium colombiense, using experimental models of progressive pulmonary tuberculosis and subcutaneous infection in BALB/c mice. Mice infected intratracheally with a high dose of MAC strains showed high expression of tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthase with rapid bacillus elimination and numerous granulomas, but without lung consolidation during late infection in coexistence with high expression of anti-inflammatory cytokines. In contrast, subcutaneous infection showed high production of the proinflammatory cytokines TNF-α and gamma interferon with relatively low production of anti-inflammatory cytokines such as interleukin-10 (IL-10) or IL-4, which efficiently eliminate the bacilli but maintain extensive inflammation and fibrosis. Thus, MAC infection evokes different immune and inflammatory responses depending on the MAC species and affected tissue. PMID:23959717

  9. Proposal to elevate the genetic variant MAC-A, included in the Mycobacterium avium complex, to species rank as Mycobacterium chimaera sp. nov.

    PubMed

    Tortoli, Enrico; Rindi, Laura; Garcia, Maria J; Chiaradonna, Patrizia; Dei, Rosanna; Garzelli, Carlo; Kroppenstedt, Reiner M; Lari, Nicoletta; Mattei, Romano; Mariottini, Alessandro; Mazzarelli, Gianna; Murcia, Martha I; Nanetti, Anna; Piccoli, Paola; Scarparo, Claudio

    2004-07-01

    The possibility that the strains included within the Mycobacterium avium complex (MAC), but not belonging either to M. avium or to Mycobacterium intracellulare, may be members of undescribed taxa, has already been questioned by several taxonomists. A very homogeneous cluster of 12 strains characterized by identical nucleotide sequences both in the 16S rDNA and in the 16S-23S internal transcribed spacer was investigated. Similar strains, previously reported in the literature, had been assigned either to the species M. intracellulare on the basis of the 16S rDNA similarity or to the group of MAC intermediates. However, several phenotypical and epidemiological characteristics seem to distinguish these strains from all other MAC organisms. The unique mycolic acid pattern obtained by HPLC is striking as it is characterized by two clusters of peaks, instead of the three presented by all other MAC organisms. All of the strains have been isolated from humans and all but one came from the respiratory tract of elderly people. The clinical significance of these strains, ascertained for seven patients, seems to suggest an unusually high virulence. The characteristics of all the strains reported in the literature, genotypically identical to the ones described here, seem to confirm our data, without reports of isolations from animals or the environment or, among humans, from AIDS patients. Therefore, an elevation of the MAC variant was proposed and characterized here, with the name Mycobacterium chimaera sp. nov.; this increases the number of species included in the M. avium complex. The type strain is FI-01069T (=CIP 107892T=DSM 44623T).

  10. Dose response models and a quantitative microbial risk assessment framework for the Mycobacterium avium complex that account for recent developments in molecular biology, taxonomy, and epidemiology.

    PubMed

    Hamilton, Kerry A; Weir, Mark H; Haas, Charles N

    2017-02-01

    Mycobacterium avium complex (MAC) is a group of environmentally-transmitted pathogens of great public health importance. This group is known to be harbored, amplified, and selected for more human-virulent characteristics by amoeba species in aquatic biofilms. However, a quantitative microbial risk assessment (QMRA) has not been performed due to the lack of dose response models resulting from significant heterogeneity within even a single species or subspecies of MAC, as well as the range of human susceptibilities to mycobacterial disease. The primary human-relevant species and subspecies responsible for the majority of the human disease burden and present in drinking water, biofilms, and soil are M. avium subsp. hominissuis, M. intracellulare, and M. chimaera. A critical review of the published literature identified important health endpoints, exposure routes, and susceptible populations for MAC risk assessment. In addition, data sets for quantitative dose-response functions were extracted from published in vivo animal dosing experiments. As a result, seven new exponential dose response models for human-relevant species of MAC with endpoints of lung lesions, death, disseminated infection, liver infection, and lymph node lesions are proposed. Although current physical and biochemical tests used in clinical settings do not differentiate between M. avium and M. intracellulare, differentiating between environmental species and subspecies of the MAC can aid in the assessment of health risks and control of MAC sources. A framework is proposed for incorporating the proposed dose response models into susceptible population- and exposure route-specific QMRA models.

  11. Mycobacterium marseillense sp. nov., Mycobacterium timonense sp. nov. and Mycobacterium bouchedurhonense sp. nov., members of the Mycobacterium avium complex.

    PubMed

    Ben Salah, Iskandar; Cayrou, Caroline; Raoult, Didier; Drancourt, Michel

    2009-11-01

    An rpoB sequence-based evaluation of 100 Mycobacterium avium complex (MAC) clinical isolates led to the identification of five respiratory tract isolates that were potential representatives of three novel MAC species. Distinctive phenotypic features of isolates 62863 and 5356591(T) included a pseudomycelium morphology and both esterase and acid phosphatase activities. These two isolates exhibited sequence similarities of 99.8 % for the 16S rRNA gene, 86.3 and 86.1 % for 16S-23S rRNA gene internal transcribed spacer (ITS-1) sequence, 96.7 and 97.8 % for rpoB and 97.6 and 97.4 % for hsp65, respectively, with the type strain of Mycobacterium chimaera, the most closely related species. Isolates 3256799 and 5351974(T) lacked alpha-mannosidase and beta-glucosidase activities. They exhibited sequence similarities of 99.6 % for the 16S rRNA gene, 90.1 and 90.4 % for ITS-1, 97.8 % for rpoB and 98.0 and 98.1 % for hsp65, respectively, with the type strain of M. chimaera, the most closely related species. Isolate 4355387(T) lacked urease and alpha-glucosidase activities, but it exhibited valine arylamidase, cystine arylamidase and acid phosphatase activities. It had sequence similarities of 99.3 % for the 16S rRNA gene, 51.8 % for ITS-1, 97.1 % for rpoB and 97.8 % for hsp65 with the type strain of Mycobacterium colombiense, the most closely related species. A phylogenetic tree based on concatenated 16S rRNA gene, ITS-1, rpoB and hsp65 sequences showed the uniqueness of these five isolates as representatives of three novel species, with bootstrap values >/=95 % in all nodes. On the basis of these phenotypic and genetic characteristics, these five isolates are proposed as representatives of three novel MAC species: Mycobacterium marseillense sp. nov., with strain 5356591(T) (=CCUG 56325(T) =CIP 109828(T) =CSUR P30(T)) as the type strain; Mycobacterium timonense sp. nov., with strain 5351974(T) (=CCUG 56329(T) =CIP 109830(T) =CSUR P32(T)) as the type strain; and Mycobacterium

  12. Complex slow potential generators in a simplified attention paradigm.

    PubMed

    Basile, Luis F H; Brunetti, Enzo P; Pereira, José F; Ballester, Gerson; Amaro, Edson; Anghinah, Renato; Ribeiro, Pedro; Piedade, Roberto; Gattaz, Wagner F

    2006-08-01

    We have recently obtained evidence for complex multifocal, individually variable generators of slow cortical potentials, elicited during performance of visual tasks involving expecting attention, comparison and memory [Basile, L.F.H., Ballester, G., Castro, C.C., and Gattaz, W.F., 2002. Multifocal slow potential generators revealed by high-resolution EEG and current density reconstruction. Int. J. Psychophysiol., 45 (3), 227-240; Basile, L.F.H, Baldo, M.V., Castro, C.C., and Gattaz, W.F. 2003. The generators of slow potentials obtained during verbal, pictorial and spatial tasks. Int. J. Psychophysiol., 48, 55-65]. The cue-target aspect of traditional paradigms for attention studies is equivalent to 'warning S1'-'imperative S2' in slow potential designs. We simplified Posner's spatial cueing task [Posner, M.I. 1980. Orienting of attention.Q. J. Exp. Psychol. Feb;32 (1), 3-25; Posner, M.I., Snyder, C.R., Davidson, B.J. 1980. Attention and the detection of signals. J Exp Psychol. Jun; 109 (2), 160-174] to temporal cuing only, by using visual cues to indicate the mere presence, on a known central position, of the eventual target (17 ms duration, +/-0.3 degrees grey circle). We recorded slow potentials on 12 healthy subjects, by 124-channel EEG system (Neuroscan Inc.), and modeled their generators using current density reconstruction (CDR) by L(p) 1.2 norm minimization ("Curry V4.6", Neurosoft Inc.) applied to the target onset time. MRIs were obtained for each subject for constraining source models to individual brain anatomy. Average slow potentials were computed from above 60 artifact-free EEG-epochs (ISI=1.6 s, average ITI=2.5 s). We tabulated individual cortical current distributions by cytoarchitectonic area of Brodmann, after scaling into negligible, low, moderate and strong local density, based on percentile bands with respect to absolute maximum current. Despite the task's simplicity, the main result was individual variability and complexity in both scalp

  13. Antigenicity in sheep of synthetic peptides derived from stress-regulated Mycobacterium avium subsp. paratuberculosis proteins and comparison with recombinant protein and complex native antigens.

    PubMed

    Gurung, Ratna B; Begg, Douglas J; Purdie, Auriol C; Whittington, Richard J

    2014-03-15

    Serum antibody enzyme-linked immunosorbent assay is the most commonly used test for diagnosis of Mycobacterium avium subsp. paratuberculosis infection in ruminants. However, the assay requires serum preabsorption with Mycobacterium phlei proteins to reduce cross reactions potentially contributed by the exposure of livestock to environmental mycobacteria. To trial the discovery of novel antigens which do not require serum absorption, synthetic MAP-specific peptides were selected based on in silico research to identify putative B cell epitopes. Four peptides from previously identified stress-regulated proteins were synthesized and evaluated using enzyme linked immunosorbent assay to detect Mycobacterium avium subsp. paratuberculosis specific antibodies in sheep. Two peptides were from hypothetical MAP proteins (MAP3567 and MAP1168c) and two were from proteins with known function (MAP2698c, an acyl-acyl carrier protein desaturase-DesA2 and MAP2487c a carbonic anhydrase). The ability of each peptide to discriminate between unexposed and MAP exposed (infected and vaccinated) animals was similar to that of the parent recombinant MAP antigen, with area under receiver operating curve values of 0.86-0.93. Assays run with a combination of two peptides showed slightly higher reactivity than those of individual peptides. Peptides evaluated in this study had diagnostic potential similar to corresponding recombinant proteins but not superior to a complex native MAP antigen or a commercial assay. Further study is required to investigate other peptides for their diagnostic potential, and this may be simpler and cheaper than subunit protein-based research.

  14. Changes in Serum IgA Antibody Levels against the Glycopeptidolipid Core Antigen during Antibiotic Treatment of Mycobacterium avium Complex Lung Disease.

    PubMed

    Jhun, Byung Woo; Kim, Su-Young; Park, Hye Yun; Jeon, Kyeongman; Shin, Sung Jae; Koh, Won-Jung

    2017-03-28

    We evaluated serial changes in the levels of serum immunoglobulin A (IgA) antibody to the glycopeptidolipid (GPL) core antigen during antibiotic treatment in 57 patients with M. avium complex (MAC) lung disease, at baseline (T0) and after 3 months (T3) and 6 months (T6) of treatment. The median patient age was 59 years and 37 (65%) were female. Etiologic organisms included M. avium in 32 (56%) patients and M. intracellulare in 25 (44%). Seven (12%) patients had the fibrocavitary form of the disease on computed tomography. After 12 months of treatment, 42 (74%) patients achieved favorable responses, whereas 15 (26%) patients had unfavorable responses defined as no sputum culture conversion within 12 months of treatment. The initial median serum anti-GPL IgA levels in the 57 patients was 3.50 U/mL, and measurements at T0 (median 3.50 U/mL), T3 (median 2.71 U/mL), and T6 (median 2.61 U/mL) revealed significant decreases following treatment (P < 0.001). Multivariate analysis showed that an initially elevated anti-GPL IgA level (> 3.50 U/mL) was associated with an unfavorable response (P = 0.049). Our data suggest that elevated anti-GPL IgA levels may reflect disease activity, which may help to predict treatment response in patients with MAC lung disease.

  15. Complexity, Training Paradigm Design, and the Contribution of Memory Subsystems to Grammar Learning

    PubMed Central

    Ettlinger, Marc; Wong, Patrick C. M.

    2016-01-01

    Although there is variability in nonnative grammar learning outcomes, the contributions of training paradigm design and memory subsystems are not well understood. To examine this, we presented learners with an artificial grammar that formed words via simple and complex morphophonological rules. Across three experiments, we manipulated training paradigm design and measured subjects' declarative, procedural, and working memory subsystems. Experiment 1 demonstrated that passive, exposure-based training boosted learning of both simple and complex grammatical rules, relative to no training. Additionally, procedural memory correlated with simple rule learning, whereas declarative memory correlated with complex rule learning. Experiment 2 showed that presenting corrective feedback during the test phase did not improve learning. Experiment 3 revealed that structuring the order of training so that subjects are first exposed to the simple rule and then the complex improved learning. The cumulative findings shed light on the contributions of grammatical complexity, training paradigm design, and domain-general memory subsystems in determining grammar learning success. PMID:27391085

  16. Complexity, Training Paradigm Design, and the Contribution of Memory Subsystems to Grammar Learning.

    PubMed

    Antoniou, Mark; Ettlinger, Marc; Wong, Patrick C M

    2016-01-01

    Although there is variability in nonnative grammar learning outcomes, the contributions of training paradigm design and memory subsystems are not well understood. To examine this, we presented learners with an artificial grammar that formed words via simple and complex morphophonological rules. Across three experiments, we manipulated training paradigm design and measured subjects' declarative, procedural, and working memory subsystems. Experiment 1 demonstrated that passive, exposure-based training boosted learning of both simple and complex grammatical rules, relative to no training. Additionally, procedural memory correlated with simple rule learning, whereas declarative memory correlated with complex rule learning. Experiment 2 showed that presenting corrective feedback during the test phase did not improve learning. Experiment 3 revealed that structuring the order of training so that subjects are first exposed to the simple rule and then the complex improved learning. The cumulative findings shed light on the contributions of grammatical complexity, training paradigm design, and domain-general memory subsystems in determining grammar learning success.

  17. Contributions of the complexity paradigm to the understanding of Cerrado's organization and dynamics.

    PubMed

    Mattos, Sérgio H V L DE; Vicente, Luiz E; Perez, Archimedes; Piqueira, José R C

    2016-01-01

    The Brazilian Cerrado is a vegetation mosaic composed of different physiognomies. Discussions remain open regarding the factors and processes responsible for the dynamic and spatial organization of the Cerrado - in its different physiognomies. The contributions of the complexity paradigm in this context are still less exploited, despite its great potential for explanations and predictions presented in previous diverse dynamic systems of complex behavior researches, a category in which the Cerrado can be included. This article has the intention of contributing to the construction of this new perspective, discussing - from theoretical concepts - the paradigm of complexity for the understanding of the organization and the dynamics of the Cerrado.

  18. Disseminated Mycobacterium avium complex infection in a child with partial dominant interferon gamma receptor 1 deficiency in India.

    PubMed

    Sharma, Varun K; Pai, Gautham; Deswarte, Caroline; Lodha, Rakesh; Singh, Sarman; Kang, Liew Woei; Yin, Chong Chia; Casanova, Jean-Laurent; Bustamante, Jacinta; Kabra, Sushil K

    2015-07-01

    Mendelian susceptibility to mycobacterial disease (MSMD) is a rare condition characterized by clinical disease caused by weakly virulent mycobacteria. All genes mutated in MSMD patients are involved in IFN-γ immunity. Autosomal partial dominant (PD) interferon-γ receptor 1 (IFN-γR1) deficiency is the most frequent abnormality affecting the group of MSMD patients leading to impaired response of IFN-γ. We describe here a patient from India with disseminated infection due to Mycobacterium avium intracellulare (MAC) including multifocal osteomyelitis and BCG disease. A heterozygous mutation in exon 6 of IFNGR1 gene was identified, conferring an autosomal PD IFN-γR1 deficiency. Patient had recurrence of mycobacterial disease during antibiotic therapy for which subcutaneous IFN-γ was added as a modality of treatment for resistant MAC infection.

  19. Toward a Complexity Paradigm for Understanding Gender Role Conflict

    ERIC Educational Resources Information Center

    Enns, Carolyn Zerbe

    2008-01-01

    The well-developed body of theory and research on men's gender role conflict provides an excellent foundation for developing increasingly complex models of men's gender-related concerns. Theorists and researchers are encouraged to incorporate themes related to social structural aspects of gender as well as to examine the ways in which men's…

  20. Paradigms of Complexity: Fractals and Structures in the Sciences

    NASA Astrophysics Data System (ADS)

    Novak, Miroslav M.

    The Table of Contents for the book is as follows: * Preface * The Origin of Complexity (invited talk) * On the Existence of Spatially Uniform Scaling Laws in the Climate System * Multispectral Backscattering: A Fractal-Structure Probe * Small-Angle Multiple Scattering on a Fractal System of Point Scatterers * Symmetric Fractals Generated by Cellular Automata * Bispectra and Phase Correlations for Chaotic Dynamical Systems * Self-Organized Criticality Models of Neural Development * Altered Fractal and Irregular Heart Rate Behavior in Sick Fetuses * Extract Multiple Scaling in Long-Term Heart Rate Variability * A Semi-Continous Box Counting Method for Fractal Dimension Measurement of Short Single Dimension Temporal Signals - Preliminary Study * A Fractional Brownian Motion Model of Cracking * Self-Affine Scaling Studies on Fractography * Coarsening of Fractal Interfaces * A Fractal Model of Ocean Surface Superdiffusion * Stochastic Subsurface Flow and Transport in Fractal Fractal Conductivity Fields * Rendering Through Iterated Function Systems * The σ-Hull - The Hull Where Fractals Live - Calculating a Hull Bounded by Log Spirals to Solve the Inverse IFS-Problem by the Detected Orbits * On the Multifractal Properties of Passively Convected Scalar Fields * New Statistical Textural Transforms for Non-Stationary Signals: Application to Generalized Mutlifractal Analysis * Laplacian Growth of Parallel Needles: Their Mullins-Sekerka Instability * Entropy Dynamics Associated with Self-Organization * Fractal Properties in Economics (invited talk) * Fractal Approach to the Regional Seismic Event Discrimination Problem * Fractal and Topological Complexity of Radioactive Contamination * Pattern Selection: Nonsingular Saffman-Taylor Finger and Its Dynamic Evolution with Zero Surface Tension * A Family of Complex Wavelets for the Characterization of Singularities * Stabilization of Chaotic Amplitude Fluctuations in Multimode, Intracavity-Doubled Solid-State Lasers * Chaotic

  1. Challenging the Limits of Critique in Education through Morin's Paradigm of Complexity

    ERIC Educational Resources Information Center

    Alhadeff-Jones, Michel

    2010-01-01

    The position adopted in this paper is inspired by Edgar Morin's paradigm of complexity and his critique of scientific and philosophical forms of reductionism. This paper is based on research focusing on the diversity of conceptions of critique developed in academic discourses. It aims to challenge the fragmentation and the reduction framing the…

  2. Complexity aided design. The FuturICT technological innovation paradigm

    NASA Astrophysics Data System (ADS)

    Carbone, A.; Ajmone-Marsan, M.; Axhausen, K. W.; Batty, M.; Masera, M.; Rome, E.

    2012-11-01

    "In the next century, planet earth will don an electronic skin. It will use the Internet as a scaffold to support and transmit its sensations. This skin is already being stitched together. It consists of millions of embedded electronic measuring devices: thermostats, pressure gauges, pollution detectors, cameras, microphones, glucose sensors, EKGs, electroencephalographs. These will probe and monitor cities and endangered species, the atmosphere, our ships, highways and fleets of trucks, our conversations, our bodies-even our dreams ....What will the earth's new skin permit us to feel? How will we use its surges of sensation? For several years-maybe for a decade-there will be no central nervous system to manage this vast signaling network. Certainly there will be no central intelligence...some qualities of self-awareness will emerge once the Net is sensually enhanced. Sensuality is only one force pushing the Net toward intelligence". These statements are quoted by an interview by Cherry Murray, Dean of the Harvard School of Engineering and Applied Sciences and Professor of Physics. It is interesting to outline the timeliness and highly predicting power of these statements. In particular, we would like to point to the relevance of the question "What will the earth's new skin permit us to feel?" to the work we are going to discuss in this paper. There are many additional compelling questions, as for example: "How can the electronic earth's skin be made more resilient?"; "How can the earth's electronic skin be improved to better satisfy the need of our society?";"What can the science of complex systems contribute to this endeavour?"

  3. Descriptive analysis of the prevalence and the molecular epidemiology of Mycobacterium avium complex-infected pigs that were slaughtered on the main island of Okinawa.

    PubMed

    Hibiya, K; Kazumi, Y; Nishiuchi, Y; Sugawara, I; Miyagi, K; Oda, Y; Oda, E; Fujita, J

    2010-09-01

    Recent genetic studies have revealed that several epidemiological factors affect Mycobacterium avium complex (MAC) infection in pig populations. However, mechanisms underlying the spread of MAC infection among hog farms have not been clarified. In consideration of this situation, we cross-sectionally investigated the mechanisms underlying the spread of MAC on the island of Okinawa. Pigs slaughtered (n=706,763) and 331 hog farms on Okinawa were surveyed during the years 2002-2004. Two outbreaks of MAC infection were occurred in several farms during survey period. Bacteria were isolated from randomly selected pigs and genotype of isolates was determined by using genetic finger printing methods with the insertion sequence (IS) 1245 restriction fragment length polymorphism (RFLP). Most isolates had large numbers of IS1245 copies, while strains with low copy numbers of IS1245 and isolates without IS1245 were seen in few farms. MACs strains were repeatedly isolated from pigs of the affected farms during the survey period. Those farms with an identical pig rearing systems showed synchronic changes in the prevalence of MAC infection. An industrial farm without an outbreak had an independent pig flow, but maintained distinct MAC strains. Multivariate analysis did not reveal independent factors for the prevalence of the MAC infection. These findings suggest that there were three clusters distinguished genetically in the main island of Okinawa, which were potentially spread by common pig flow. However, the outbreaks occurred because of unspecified conditions on each farm environment.

  4. Attenuation of lymphocyte immune responses during Mycobacterium avium complex-induced lung disease due to increasing expression of programmed death-1 on lymphocytes

    PubMed Central

    Shu, Chin-Chung; Wang, Jann-Yuan; Wu, Ming-Fang; Wu, Chen-Tu; Lai, Hsin-Chih; Lee, Li-Na; Chiang, Bor-Luen; Yu, Chong-Jen

    2017-01-01

    Mycobacterium avium complex-induced lung disease (MAC-LD) becomes important due to its increasing prevalence. Attenuated cellular immunity associated with programmed cell death (PD)–1 may play a pathophysiological role in MAC-LD but lacks of investigation. We enrolled 80 participants in this prospective study, including 50 with MAC-LD and 30 healthy controls. Peripheral blood mononuclear cells (PBMCs), lymphocytes and monocyte-derived macrophages were used for MAC antigen stimulation. Patients with MAC-LD had lower tumor necrosis factor-α and interferon-γ responses compared to the healthy controls in PBMC stimulation assays with MAC bacilli. These responses improved after MAC treatment. The PD-1 and PD ligand expressions and apoptosis were higher in the lymphocytes of the patients with MAC-LD compared to the controls. Both PD-1 and apoptosis on T lymphocytes were significantly increased in the patients with MAC-LD, either by direct MAC stimulation or by MAC-primed macrophage activation. Partially blocking PD-1 and the PD ligand with antagonizing antibodies in the stimulation assay significantly increased the cytokine production of IFN-γ and decreased the apoptosis on T lymphocytes. In conclusion, the patients with MAC-LD have attenuated lymphocyte immunity, which might be associated with increasing activation of PD-1 and PD-1 ligand. Regulating such activation might improve the lymphocytic secretion of IFN-γ and reduce apoptosis. PMID:28169347

  5. Relationship between IS901 in the Mycobacterium avium Complex Strains Isolated from Birds, Animals, Humans, and the Environment and Virulence for Poultry

    PubMed Central

    Pavlik, Ivo; Svastova, Petra; Bartl, Jiri; Dvorska, Lenka; Rychlik, Ivan

    2000-01-01

    A total of 738 strains of Mycobacterium avium complex (MAC) were examined in biological experiments on poultry by use of PCR methods with primers for detection of the insertion sequence IS901. Serotype strains of MAC from all known 28 serotypes were examined. Further strains were isolated from human immunodeficiency virus (HIV)-negative and HIV-positive patients, 6 animal species, 17 bird species, and the environment. Of 165 strains virulent for poultry, characterized by generalized tuberculosis, 164 strains contained IS901, a result which is statistically highly significant (P, 0.01). The remaining 573 strains were nonvirulent; however, IS901 was present in 24 strains. From among 20 strains of serotypes 1, 2, and 3, IS901 was found in 15 strains, only 5 of which were virulent for poultry. The remaining 111 strains, of serotypes 4 to 28, were nonvirulent and did not incorporate IS901. None of the 152 strains isolated from humans was virulent for poultry, including 12 strains which were IS901 positive. PMID:10702495

  6. An eye-tracking paradigm for analyzing the processing time of sentences with different linguistic complexities.

    PubMed

    Wendt, Dorothea; Brand, Thomas; Kollmeier, Birger

    2014-01-01

    An eye-tracking paradigm was developed for use in audiology in order to enable online analysis of the speech comprehension process. This paradigm should be useful in assessing impediments in speech processing. In this paradigm, two scenes, a target picture and a competitor picture, were presented simultaneously with an aurally presented sentence that corresponded to the target picture. At the same time, eye fixations were recorded using an eye-tracking device. The effect of linguistic complexity on language processing time was assessed from eye fixation information by systematically varying linguistic complexity. This was achieved with a sentence corpus containing seven German sentence structures. A novel data analysis method computed the average tendency to fixate the target picture as a function of time during sentence processing. This allowed identification of the point in time at which the participant understood the sentence, referred to as the decision moment. Systematic differences in processing time were observed as a function of linguistic complexity. These differences in processing time may be used to assess the efficiency of cognitive processes involved in resolving linguistic complexity. Thus, the proposed method enables a temporal analysis of the speech comprehension process and has potential applications in speech audiology and psychoacoustics.

  7. Pilot Quasi-Randomized Controlled Study of Herbal Medicine Hochuekkito as an Adjunct to Conventional Treatment for Progressed Pulmonary Mycobacterium avium Complex Disease

    PubMed Central

    Enomoto, Yasunori; Hagiwara, Eri; Komatsu, Shigeru; Nishihira, Ryuichi; Baba, Tomohisa; Kitamura, Hideya; Sekine, Akimasa; Nakazawa, Atsuhito; Ogura, Takashi

    2014-01-01

    Introduction Hochuekkito, a traditional herbal medicine, is occasionally prescribed in Japan to treat patients with a poor general condition. We aimed to examine whether this medicine was beneficial and tolerable for patients with progressed pulmonary Mycobacterium avium complex (MAC) disease. Methods This pilot open-label quasi-randomized controlled trial enrolled 18 patients with progressed pulmonary MAC disease who had initiated antimycobacterial treatment over one year ago but were persistently culture-positive or intolerant. All patients continued their baseline treatment regimens with (n = 9) or without (n = 9) oral Hochuekkito for 24 weeks. Results Baseline characteristics were generally similar between the groups. Most patients were elderly (median age 70 years), female, had a low body mass index (<20 kg/m2), and a long-term disease duration (median approximately 8 years). After the 24-week treatment period, no patient achieved sputum conversion. Although the number of colonies in sputum tended to increase in the control group, it generally remained stable in the Hochuekkito group. Radiological disease control was frequently observed in the Hochuekkito group than the control group (8/9 vs. 3/9; p = 0.05). Patients in the Hochuekkito group tended to experience increase in body weight and serum albumin level compared with those in the control group (median body weight change: +0.4 kg vs. −0.8 kg; median albumin change: +0.2 g/dl vs. ±0.0 g/dl). No severe adverse events occurred. Conclusions Hochuekkito could be an effective, feasible adjunct to conventional therapy for patients with progressed pulmonary MAC disease. Future study is needed to explore this possibility. Trial Registration UMIN Clinical Trials Registry UMIN000009920 PMID:25093868

  8. Diagnostic test accuracy of anti-glycopeptidolipid-core IgA antibodies for Mycobacterium avium complex pulmonary disease: systematic review and meta-analysis

    PubMed Central

    Shibata, Yuji; Horita, Nobuyuki; Yamamoto, Masaki; Tsukahara, Toshinori; Nagakura, Hideyuki; Tashiro, Ken; Watanabe, Hiroki; Nagai, Kenjiro; Nakashima, Kentaro; Ushio, Ryota; Ikeda, Misako; Narita, Atsuya; Kanai, Akinori; Sato, Takashi; Kaneko, Takeshi

    2016-01-01

    Currently, an anti-glycopeptidolipid (GPL)-core IgA antibody assay kit for diagnosing Mycobacterium avium complex (MAC) is commercially available. We conducted this systematic review and meta-analysis to reveal the precise diagnostic accuracy of anti-GPL-core IgA antibodies for MAC pulmonary disease (MAC-PD). We systematically searched reports that could provide data for both sensitivity and specificity by anti-GPL-core IgA antibody for clinically diagnosed MAC-PD. Diagnostic test accuracy was estimated using the bivariate model. Of the 257 articles that we had found through primary search, we finally included 16 reports consisted of 1098 reference positive subjects and 2270 reference negative subjects. The diagnostic odds ratio was 24.8 (95% CI 11.6–52.8, I2 = 5.5%) and the area under the hierarchical summary receiver operating characteristic curves was 0.873 (95% CI 0.837–0.913). With a cutoff value of 0.7 U/mL, the summary estimates of sensitivity and specificity were 0.696 (95% CI 0.621–0.761) and 0.906 (95% CI 0.836–0.951), respectively. The positive and negative likelihood ratios were 7.4 (95% CI 4.1–13.8) and 0.34 (95% CI 0.26–0.43), respectively. The demanding clinical diagnostic criteria may be a cause of false positive of the index test. The index test had good overall diagnostic accuracy and was useful to ruling in MAC-PD with the cutoff value. PMID:27373718

  9. Characterization of clinical and environmental Mycobacterium avium spp. isolates and their interaction with human macrophages

    EPA Science Inventory

    Members of the Mycobacterium avium complex (MAC) are naturally occurring bacteria in the environment. A link has been suggested between M. avium strains in drinking water and clinical isolates from infected individuals. There is a need to develop new screening methodologies tha...

  10. Clinical findings in relation to mortality in non-tuberculous mycobacterial infections: patients with Mycobacterium avium complex have better survival than patients with other mycobacteria.

    PubMed

    Kotilainen, H; Valtonen, V; Tukiainen, P; Poussa, T; Eskola, J; Järvinen, A

    2015-09-01

    We compared the clinical findings and survival in patients with Mycobacterium avium complex (MAC) and other non-tuberculous mycobacteria (NTM). A total of 167 adult non-human immunodeficiency virus (HIV) patients with at least one positive culture for NTM were included. Medical records were reviewed. The patients were categorised according to the 2007 American Thoracic Society (ATS) criteria. MAC comprised 59 % of all NTM findings. MAC patients were more often female (70 % vs. 34 %, p < 0.001) and had less fatal underlying diseases (23 % vs. 47 %, p = 0.001) as compared to other NTM patients. Symptoms compatible with NTM infection had lasted for less than a year in 34 % of MAC patients but in 54 % of other NTM patients (p = 0.037). Pulmonary MAC patients had a significantly lower risk of death compared to pulmonary other NTM (hazard ratio [HR] 0.50, 95 % confidence interval [CI] 0.33-0.77, p = 0.002) or subgroup of other slowly growing NTM (HR 0.55, 95 % CI 0.31-0.99, p = 0.048) or as rapidly growing NTM (HR 0.47, 95 % CI 0.25-0.87, p = 0.02). The median survival time was 13.0 years (95 % CI 5.9-20.1) for pulmonary MAC but 4.6 years (95 % CI 3.4-5.9) for pulmonary other NTM. Serious underlying diseases (HR 3.21, 95 % CI 2.05-5.01, p < 0.001) and age (HR 1.07, 95 % CI 1.04-1.09, p < 0.001) were the significant predictors of mortality and female sex was a predictor of survival (HR 0.38, 95 % CI 0.24-0.59, p < 0.001) in the multivariate analysis. Pulmonary MAC patients had better prognosis than pulmonary other NTM patients. The symptom onset suggests a fairly rapid disease course.

  11. IS1311 and IS1245 Restriction Fragment Length Polymorphism Analyses, Serotypes, and Drug Susceptibilities of Mycobacterium avium Complex Isolates Obtained from a Human Immunodeficiency Virus-Negative Patient

    PubMed Central

    Dvorska, Lenka; Bartos, Milan; Ostadal, Oldrich; Kaustova, Jarmila; Matlova, Ludmila; Pavlik, Ivo

    2002-01-01

    Six isolates of Mycobacterium avium of genotype dnaJ+ IS901− IS1311+ IS1245+ and serotypes 6 (n = 1), 6/9, (n = 2), and 9 (n = 3) were obtained within a 5-month period from a human immunodeficiency virus-negative patient treated for tuberculosis. The isolates were identified with PvuII restriction fragment length polymorphism (RFLP) analysis as a single IS1311 RFLP type and six different IS1245 RFLP types. Six separate colonies/clones obtained by subculture from each of the six isolates were tested for MICs of a set of 10 drugs. This report documents the appearance of isolates that are resistant to antimycobacterial drugs as the duration of therapy increases. Because isolates recovered from the patient following longer duration of treatment were more likely to be resistant to more antimycobacterial drugs, we would conclude that there was selection for antimycobacterial drug-resistant isolates. Analyses of all 36 clones identified three IS1311 and 22 IS1245 types forming three clusters. Tests of 105 environmental samples collected in the home and the work place of the patient yielded 16 mycobacterial isolates, of which one M. avium from soil was of genotype dnaJ+ IS901+ IS1311+ IS1245+ and serotype 2, and the second M. avium from a vacuum cleaner was of genotype dnaJ+ IS901− IS1311+ IS1245+ and serotype 9. Overall analyses of the results did not reveal any relation between serotype, RFLP type, and drug susceptibility. Based on the course of the disease in the patient and different serotypes, IS1311 and IS1245 RFLP types of isolates of M. avium we suppose represent polyclonal infection. PMID:12354870

  12. Paradigms in the structural biology of the mitogenic ternary complex FGF:FGFR:heparin.

    PubMed

    Pomin, Vitor H

    2016-08-01

    The main achievements regarding the molecular interaction involving fibroblast growth factors (FGFs), canonical receptors (FGFRs) and the glycosaminoglycans (GAGs) heparan sulfate (HS)/heparin (Hp) are overviewed. Despite the recent works concerning the subject, conflicting paradigms in the structural biology of the resultant ternary complex FGF:FGFR:HS/Hp seem to persist up to these days. The principal dilemma, centered on the functional intermolecular complex of mitogenesis and angiogenesis, has been lasting for approximately a decade and a half since the publications of the two contradicting crystal structures, the asymmetric 2:2:1 versus the symmetric 2:2:2 complex model. When the principal results regarding this ternary complex are analyzed as a whole and through an impartial manner, conclusion heavily and reliably supports the existence and activity of both complex models. Selection of each complex is driven by multiple factors of different degrees of impact. Specificity in protein-binding motifs in ligands (although the minimal binding sequences are yet controversial), slight differences on the structure of the GAG-binding sites of FGF and of FGFR isoforms as well as on the possible ligand-induced conformational changes of FGFR are examples of these factors. Here, the structural biology of the mitogenic FGF:FGFR:HS/Hp ternary complex is revisited. Discussion is focused on the major attributes of this intermolecular complex including the existing conflicts about the righter biologically active model and information regarding ligand structure, conformation and minimal length required for binding to the growth factors and receptors. This review is very timely in light of the 100(th) anniversary of the discovery of Hp.

  13. Using Common Graphics Paradigms Implemented in a Java Applet to Represent Complex Scheduling Requirements

    NASA Technical Reports Server (NTRS)

    Jaap, John; Meyer, Patrick; Davis, Elizabeth

    1997-01-01

    The experiments planned for the International Space Station promise to be complex, lengthy and diverse. The scarcity of the space station resources will cause significant competition for resources between experiments. The scheduling job facing the Space Station mission planning software requires a concise and comprehensive description of the experiments' requirements (to ensure a valid schedule) and a good description of the experiments' flexibility (to effectively utilize available resources). In addition, the continuous operation of the station, the wide geographic dispersion of station users, and the budgetary pressure to reduce operations manpower make a low-cost solution mandatory. A graphical representation of the scheduling requirements for station payloads implemented via an Internet-based application promises to be an elegant solution that addresses all of these issues. The graphical representation of experiment requirements permits a station user to describe his experiment by defining "activities" and "sequences of activities". Activities define the resource requirements (with alternatives) and other quantitative constraints of tasks to be performed. Activities definitions use an "outline" graphics paradigm. Sequences define the time relationships between activities. Sequences may also define time relationships with activities of other payloads or space station systems. Sequences of activities are described by a "network" graphics paradigm. The bulk of this paper will describe the graphical approach to representing requirements and provide examples that show the ease and clarity with which complex requirements can be represented. A Java applet, to run in a web browser, is being developed to support the graphical representation of payload scheduling requirements. Implementing the entry and editing of requirements via the web solves the problems introduced by the geographic dispersion of users. Reducing manpower is accomplished by developing a concise

  14. "To Give an Example Is a Complex Act": Agamben's Pedagogy of the Paradigm

    ERIC Educational Resources Information Center

    Meskin, Jacob; Shapiro, Harvey

    2014-01-01

    Agamben's notion of the "paradigm" has far-reaching implications for educational thinking, curriculum design and pedagogical conduct. In his approach, examples--or paradigms--deeply engage our powers of analogy, enabling us to discern previously unseen affinities among singular objects by stepping outside established systems of…

  15. In vitro activity of amikacin against isolates of Mycobacterium avium complex with proposed MIC breakpoints and finding of a 16S rRNA gene mutation in treated isolates.

    PubMed

    Brown-Elliott, Barbara A; Iakhiaeva, Elena; Griffith, David E; Woods, Gail L; Stout, Jason E; Wolfe, Cameron R; Turenne, Christine Y; Wallace, Richard J

    2013-10-01

    Amikacin is a major drug used for the treatment of Mycobacterium avium complex (MAC) disease, but standard laboratory guidelines for susceptibility testing are not available. This study presents in vitro amikacin MICs for 462 consecutive clinical isolates of the MAC using a broth microdilution assay. Approximately 50% of isolates had amikacin MICs of 8 μg/ml, and 86% had MICs of ≤16 μg/ml. Of the eight isolates (1.7%) with MICs of 64 μg/ml, five had an MIC of 32 μg/ml on repeat testing. Ten isolates (2.1%) had an initial amikacin MIC of >64 μg/ml, of which seven (1.5%) had MICs of >64 μg/ml on repeat testing. These seven isolates had a 16S rRNA gene A1408G mutation and included M. avium, Mycobacterium intracellulare, and Mycobacterium chimaera. Clinical data were available for five of these seven isolates, all of which had received prolonged (>6 months) prior therapy, with four that were known to be treated with amikacin. The 16S mutation was not detected in isolates with MICs of ≤64 μg/ml. We recommend primary testing of amikacin against isolates of the MAC and propose MIC guidelines for breakpoints that are identical to the CLSI guidelines for Mycobacterium abscessus: ≤16 μg/ml for susceptible, 32 μg/ml for intermediate, and ≥64 μg/ml for resistant. If considered and approved by the CLSI, this will be only the second drug recommended for primary susceptibility testing against the MAC and should facilitate its use for both intravenous and inhaled drug therapies.

  16. Characterization of a Mycobacterium avium subsp. avium Operon Associated with Virulence and Drug Detoxification

    PubMed Central

    Viale, Mariana Noelia; Imperiale, Belén; Gioffre, Andrea Karina; Colombatti Olivieri, María Alejandra; Moyano, Roberto Damián; Morcillo, Nora; Santangelo, María de la Paz; Davis, William; Romano, María Isabel

    2014-01-01

    The lprG-p55 operon of Mycobacterium tuberculosis and Mycobacterium bovis is involved in the transport of toxic compounds. P55 is an efflux pump that provides resistance to several drugs, while LprG is a lipoprotein that modulates the host's immune response against mycobacteria. The knockout mutation of this operon severely reduces the replication of both mycobacterial species during infection in mice and increases susceptibility to toxic compounds. In order to gain insight into the function of LprG in the Mycobacterium avium complex, in this study, we assayed the effect of the deletion of lprG gene in the D4ER strain of Mycobacterium avium subsp. avium. The replacement of lprG gene with a hygromycin cassette caused a polar effect on the expression of p55. Also, a twofold decrease in ethidium bromide susceptibility was observed and the resistance to the antibiotics rifampicin, amikacin, linezolid, and rifabutin was impaired in the mutant strain. In addition, the mutation decreased the virulence of the bacteria in macrophages in vitro and in a mice model in vivo. These findings clearly indicate that functional LprG and P55 are necessary for the correct transport of toxic compounds and for the survival of MAA in vitro and in vivo. PMID:24967408

  17. Lymphadenitis in children is caused by Mycobacterium avium hominissuis and not related to ‘bird tuberculosis’

    PubMed Central

    de Haas, P. E. W.; Lindeboom, J. A.; Kuijper, E. J.; van Soolingen, D.

    2008-01-01

    Mycobacterium avium is the most commonly encountered mycobacterium species among non-Mycobacterium tuberculosis complex (nontuberculous mycobacteria) isolates worldwide and frequently causes lymphadenitis in children. During a multi-centre study in The Netherlands that was performed to determine the optimal treatment for mycobacterial lymphadenitis, concern was expressed in the media about the possible role of birds as sources of these M. avium infections, referred to as ‘bird tuberculosis.’ To examine the involvement of birds in mycobacterial lymphadenitis, 34 M. avium isolates from lymphadenitis cases were subjected to IS1245 restriction fragment length polymorphism (RFLP) typing. This genotyping method enables the distinction of the subspecies M. avium subsp. hominissuis and the ‘bird-type’ M. avium spp. avium. Highly variable RFLP patterns were found among the lymphadenitis M. avium isolates, and all belonged to the M. avium hominissuis subspecies. A relation to pet birds in the etiology of mycobacterial lymphadenitis could not be established, and the source of the infections may be environmental. PMID:18320245

  18. Genotyping of Mycobacterium avium subsp. avium isolates from naturally infected lofts of domestic pigeons in Ahvaz by IS901 RFLP

    PubMed Central

    Parvandar-Asadollahi, Kaveh; Mosavari, Nader; Mayahi, Mansoor

    2015-01-01

    Background and Objectives: Avian tuberculosis is one of the most important infections affecting most species of birds. Mycobacterium avium can not only infect all species of birds, but also infect some domesticated mammals. The most crucial aspect of control and eradication scheme is identification of infection sources and transmission routs. Molecular techniques such as restriction fragment length polymorphism and pulse field gel electrophoresis have been shown to be much more discriminatory and suitable for use in the epidemiological study. Materials and Methods: Eighty suspected pigeons to avian tuberculosis based on their clinical signs, were subjected to the study. Forty Mycobacterium avium subsp. avium isolates out of a total of 51 identified isolates were subjected to the test. Results: IS901-RFLP using Pvu II was successfully conducted and produced 7 patterns. The majority of isolates (60%) were RFLP type PI.1. This type was the most similar type to standard strain. However, all the patterns obtained in this study were different from the standard strain. Conclusion: The result of this study indicate that these isolates probably are limited to Khuzestan region. We recommend DNA fingerprinting differentiation of non tuberculous Mycobacteria particularly Mycobacterium avium complex isolated from infected birds and human to possibly find source of infections. PMID:26719782

  19. Mycobacterium avium MAV2054 protein induces macrophage apoptosis by targeting mitochondria and reduces intracellular bacterial growth

    PubMed Central

    Lee, Kang-In; Whang, Jake; Choi, Han-Gyu; Son, Yeo-Jin; Jeon, Haet Sal; Back, Yong Woo; Park, Hye-Soo; Paik, Seungwha; Park, Jeong-Kyu; Choi, Chul Hee; Kim, Hwa-Jung

    2016-01-01

    Mycobacterium avium complex induces macrophage apoptosis. However, the M. avium components that inhibit or trigger apoptosis and their regulating mechanisms remain unclear. We recently identified the immunodominant MAV2054 protein by fractionating M. avium culture filtrate protein by multistep chromatography; this protein showed strong immuno-reactivity in M. avium complex pulmonary disease and in patients with tuberculosis. Here, we investigated the biological effects of MAV2054 on murine macrophages. Recombinant MAV2054 induced caspase-dependent macrophage apoptosis. Enhanced reactive oxygen species production and JNK activation were essential for MAV2054-mediated apoptosis and MAV2054-induced interleukin-6, tumour necrosis factor, and monocyte chemoattractant protein-1 production. MAV2054 was targeted to the mitochondrial compartment of macrophages treated with MAV2054 and infected with M. avium. Dissipation of the mitochondrial transmembrane potential (ΔΨm) and depletion of cytochrome c also occurred in MAV2054-treated macrophages. Apoptotic response, reactive oxygen species production, and ΔΨm collapse were significantly increased in bone marrow-derived macrophages infected with Mycobacterium smegmatis expressing MAV2054, compared to that in M. smegmatis control. Furthermore, MAV2054 expression suppressed intracellular growth of M. smegmatis and increased the survival rate of M. smegmatis-infected mice. Thus, MAV2054 induces apoptosis via a mitochondrial pathway in macrophages, which may be an innate cellular response to limit intracellular M. avium multiplication. PMID:27901051

  20. Emergence and decline of scientific paradigms in a dynamic complex network.

    PubMed

    Yao, Chao; Zhang, Mei

    2013-01-01

    We study the idea spreading process by extending a recent model proposed by Bornholdt et al. [Phys. Rev. Lett. 106, 058701 (2011)] to the population on a two-dimensional square area either in the presence of static topological randomness or in which agents are allowed to freely move. We find that the static topological randomness induced by the random distribution of agents in the square area disfavors the common pattern of scientific paradigms, which is characterized by quick rise and slow decline of an arbitrary dominant idea. However, the common pattern of scientific paradigms is recovered when the movement of agents is enabled. In addition, we find that, when the moving speed of agents is low, the average lifetime of a dominant idea displays an optimal behavior. In contrast, the evolution of the model is no more sensitive to the movement speed once it is high enough.

  1. Isolation of Mycobacterium avium from waterfowl with polycystic livers.

    USGS Publications Warehouse

    Roffe, Thomas J.

    1989-01-01

    An unusual gross appearance of avian tuberculosis, where fluid-filled thin-walled cysts are produced and grossly apparent in preference to granulomas, is presented. Histopathology confirmed the granulomatous nature of the lesions and the presence of intracellular acid-fast organisms. Mycobacterium avium complex was cultured from affected organs. The unusual gross presentation in these cases indicates the need to consider tuberculosis in the differential of cystic diseases of avian livers.

  2. The SocioBox: A Novel Paradigm to Assess Complex Social Recognition in Male Mice.

    PubMed

    Krueger-Burg, Dilja; Winkler, Daniela; Mitkovski, Mišo; Daher, Fernanda; Ronnenberg, Anja; Schlüter, Oliver M; Dere, Ekrem; Ehrenreich, Hannelore

    2016-01-01

    Impairments in social skills are central to mental disease, and developing tools for their assessment in mouse models is essential. Here we present the SocioBox, a new behavioral paradigm to measure social recognition. Using this paradigm, we show that male wildtype mice of different strains can readily identify an unfamiliar mouse among 5 newly acquainted animals. In contrast, female mice exhibit lower locomotor activity during social exploration in the SocioBox compared to males and do not seem to discriminate between acquainted and unfamiliar mice, likely reflecting inherent differences in gender-specific territorial tasks. In addition to a simple quantification of social interaction time of mice grounded on predefined spatial zones (zone-based method), we developed a set of unbiased, data-driven analysis tools based on heat map representations and characterized by greater sensitivity. First proof-of-principle that the SocioBox allows diagnosis of social recognition deficits is provided using male PSD-95 heterozygous knockout mice, a mouse model related to psychiatric pathophysiology.

  3. The SocioBox: A Novel Paradigm to Assess Complex Social Recognition in Male Mice

    PubMed Central

    Krueger-Burg, Dilja; Winkler, Daniela; Mitkovski, Mišo; Daher, Fernanda; Ronnenberg, Anja; Schlüter, Oliver M.; Dere, Ekrem; Ehrenreich, Hannelore

    2016-01-01

    Impairments in social skills are central to mental disease, and developing tools for their assessment in mouse models is essential. Here we present the SocioBox, a new behavioral paradigm to measure social recognition. Using this paradigm, we show that male wildtype mice of different strains can readily identify an unfamiliar mouse among 5 newly acquainted animals. In contrast, female mice exhibit lower locomotor activity during social exploration in the SocioBox compared to males and do not seem to discriminate between acquainted and unfamiliar mice, likely reflecting inherent differences in gender-specific territorial tasks. In addition to a simple quantification of social interaction time of mice grounded on predefined spatial zones (zone-based method), we developed a set of unbiased, data-driven analysis tools based on heat map representations and characterized by greater sensitivity. First proof-of-principle that the SocioBox allows diagnosis of social recognition deficits is provided using male PSD-95 heterozygous knockout mice, a mouse model related to psychiatric pathophysiology. PMID:27563287

  4. Viewing Complex, Dynamic Scenes “Through the Eyes” of Another Person: The Gaze-Replay Paradigm

    PubMed Central

    Morin Duchesne, Xavier; Kagemann, Sebastian Alexander; Kennedy, Daniel Patrick

    2015-01-01

    We present a novel “Gaze-Replay” paradigm that allows the experimenter to directly test how particular patterns of visual input—generated from people’s actual gaze patterns—influence the interpretation of the visual scene. Although this paradigm can potentially be applied across domains, here we applied it specifically to social comprehension. Participants viewed complex, dynamic scenes through a small window displaying only the foveal gaze pattern of a gaze “donor.” This was intended to simulate the donor’s visual selection, such that a participant could effectively view scenes “through the eyes” of another person. Throughout the presentation of scenes presented in this manner, participants completed a social comprehension task, assessing their abilities to recognize complex emotions. The primary aim of the study was to assess the viability of this novel approach by examining whether these Gaze-Replay windowed stimuli contain sufficient and meaningful social information for the viewer to complete this social perceptual and cognitive task. The results of the study suggested this to be the case; participants performed better in the Gaze-Replay condition compared to a temporally disrupted control condition, and compared to when they were provided with no visual input. This approach has great future potential for the exploration of experimental questions aiming to unpack the relationship between visual selection, perception, and cognition. PMID:26252493

  5. Liposome encapsulation of clofazimine reduces toxicity in vitro and in vivo and improves therapeutic efficacy in the beige mouse model of disseminated Mycobacterium avium-M. intracellulare complex infection.

    PubMed Central

    Mehta, R T

    1996-01-01

    Disseminated infections caused by the Mycobacterium avium-M. intracellulare complex (MAC) are the most frequent opportunistic bacterial infections in patients with AIDS. MAC isolates are resistant to many of the standard antituberculous drugs. Failure to obtain significant activities of certain drugs is due to difficulty in achieving high concentrations at the sites where the infections reside. New and improved agents for the treatment of mycobacterial infections are therefore required. Earlier, the anti-MAC activities of various agents in free or liposomal form were studied; liposomes were used as drug carriers to ultimately target the drugs to macrophages where mycobacterial infections reside. Clofazimine was chosen for further studies because it could be effectively encapsulated and its activity was well maintained in liposomal form. The present studies with both erythrocytes and macrophages as the model systems show that liposomal drug is far less toxic in vitro than the free drug. The in vivo toxicity of clofazimine was also significantly reduced after liposome encapsulation. The therapeutic efficacies of free and liposomal drugs were compared in a beige mouse model of disseminated MAC infection. An equivalent dose of liposomal drug (10 mg/kg of body weight) was more effective in eliminating the bacterial from the various organs studied, particularly from the liver. Moreover, because of the reduced toxicity of liposomal drug, higher doses could be administered, resulting in a significant reduction in the numbers of CFU in the liver, spleen, and kidneys. The data demonstrate that liposomal clofazimine is highly effective in the treatment of MAC infections, even if the treatment is initiated after a disseminated infection has been established. The present studies thus suggest the potential usefulness of liposomal clofazimine for the treatment of disseminated MAC infections. PMID:8843300

  6. Tuberculosis in swine co-infected with Mycobacterium avium subsp. hominissuis and Mycobacterium bovis in a cluster from Argentina.

    PubMed

    Barandiaran, S; Pérez, A M; Gioffré, A K; Martínez Vivot, M; Cataldi, A A; Zumárraga, M J

    2015-04-01

    SUMMARY In Argentina little is known about the epidemiology of tuberculosis (TB) infection in swine. We characterized the epidemiological dynamics of Mycobacterium avium complex (MAC) infection in a swine population of Argentina using molecular tools and spatial analysis techniques. Isolates (n = 196) obtained from TB-like lesions (n = 200) were characterized by polymerase chain reaction. The isolates were positive to either M. bovis (IS6110) (n = 160) or M. avium (IS1245) (n = 16) while the remaining 20 (10.2%) isolates were positive to both M. bovis and M. avium. The detection of both bacteria together suggests co-infection at the animal level. In addition, MAC-positive isolates (n = 36) were classified as M. avium subsp. avium (MAA) (n = 30) and M. avium subsp. hominissuis (MAH) (n = 6), which resulted in five genotypes when they were typed using mycobacterial interspersed repetitive unit, variable number of tandem repeats (MIRU-VNTR). One significant (P = 0.017) spatial clustering of genotypes was detected, in which the proportion of MAH isolates was larger than expected under the null hypothesis of even distribution of genotypes. These results show that in Argentina the proportion of TB cases in pigs caused by M. avium is larger than that reported in earlier studies. The proportion of M. bovis-MAC co-infections was also higher than in previous reports. These results provide valuable information on the epidemiology of MAC infection in swine in Argentina.

  7. A paradigm shift in the construction of heterobimetallic complexes: synthesis of group 2 & 4 metal-calix[6]arene complexes.

    PubMed

    Petrella, Antonella J; Craig, Donald C; Lamb, Robert N; Raston, Colin L; Roberts, Nicholas K

    2004-01-21

    Deprotonation of calix[6]arenes with barium in methanol followed by the addition of [Ti(OPr(i))(4)] or [Zr(OBu(n))(4)] is effective in the formation of novel dimeric 2:1 barium-titanium(IV)/zirconium(IV) calix[6]arene complexes. In these complexes a central Ti(IV)/Zr(IV) coordinated in the exo-position connects the two calix[6]arenes in the 1,3-alternate conformation, each with an endo-barium sharing common phenolate groups with the titanium/zirconium centre and participating in cation-pi interactions. A homometallic barium calix[6]arene dimer was also prepared wherein the calix[6]arenes are in the 1,3-alternate conformation with each coordinating one endo- and one exo-barium centre. The exo-barium cations connect the two calix[6]arenes through bridging methanol ligands. In this and the heterometallic complexes, cation-pi complexation of the Ba(2+) ion within the 1,3 alternate conformation of calix[6]arene facilitates the formation of the dimeric complexes in methanol. In contrast, the smaller Sr(2+) ion did not form similar complexes in methanol, and the formation of an analogous 2:1 strontium-titanium calixarene complex required the use of the more sterically demanding donor alcohol, isopropanol, the resulting complex being devoid of cation-pi interaction. The results show (i) that a subtle interplay of solvation strength, coordination array type and cavity/cation size influences the accessibility of heterobimetallic complexes based on calix[6]arenes, and (ii) a synergistic endo-exo binding behaviour.

  8. Complexity and Chaos Theories as Potential Paradigms for Understanding and Treating Dissociative Disorders.

    NASA Astrophysics Data System (ADS)

    Drinkard, Lynne Bradford

    1995-01-01

    Early systems theory was a precursor of complexity theory, a global theory that suggests that the universe is an open system interacting on many dimensions. Chaos theory, a subset of complexity theory, states that in seeming chaos there is an underlying order. Between chaos and order lies emergence, from which healthy growth and change occur. Twenty years ago, chaos theory did not have a name and dissociative disorders were largely written off as rare or more imaginative than real. After physicists and mathematicians explained chaos and complexity in language understood by those outside their fields, scientists and practitioners from disparate disciplines were struck by the potential for applying the theories to their respective fields. Complexity and chaos theory combine reductionistic and holistic approaches to explain phenomena. Many mental health practitioners have suggested that a systems framework based in complexity theory may lead to greater understanding of human nature and ultimately toward more effective treatment of different disorders. This paper proposes that complexity and chaos theories may offer insight into the efficacy of various treatments for dissociative disorders.

  9. Clarithromycin-ciprofloxacin-amikacin for therapy of Mycobacterium avium-Mycobacterium intracellulare bacteremia in patients with AIDS.

    PubMed Central

    de Lalla, F; Maserati, R; Scarpellini, P; Marone, P; Nicolin, R; Caccamo, F; Rigoli, R

    1992-01-01

    A combination of clarithromycin, ciprofloxacin, and amikacin for the treatment of Mycobacterium avium-Mycobacterium intracellulare bacteremia was evaluated in 12 AIDS patients. Mycobacteremia cleared in all patients by 2 to 8 weeks of treatment, and symptoms resolved. Four patients died; all had negative blood cultures until death, and disseminated M. avium-M. intracellulare complex infection was not considered the primary cause of death. PMID:1387303

  10. Palatal Actinomycosis and Kaposi Sarcoma in an HIV-Infected Subject with Disseminated Mycobacterium avium-intracellulare Infection

    PubMed Central

    Ablanedo-Terrazas, Yuria; Ormsby, Christopher E.; Reyes-Terán, Gustavo

    2012-01-01

    Actinomyces and Mycobacterium avium-intracellulare are facultative intracellular organisms, members of the bacterial order actinomycetales. Although Actinomyces can behave as copathogen when anatomic barriers are compromised, its coinfection with Mycobacterium avium-intracellulare has not previously been reported. We present the first reported case of palatal actinomycosis co-infection with disseminated MAC, in an HIV-infected subject with Kaposi sarcoma and diabetes. We discuss the pathogenesis of the complex condition of this subject. PMID:22481952

  11. Bovine Immunoinhibitory Receptors Contribute to Suppression of Mycobacterium avium subsp. paratuberculosis-Specific T-Cell Responses.

    PubMed

    Okagawa, Tomohiro; Konnai, Satoru; Nishimori, Asami; Ikebuchi, Ryoyo; Mizorogi, Seiko; Nagata, Reiko; Kawaji, Satoko; Tanaka, Shogo; Kagawa, Yumiko; Murata, Shiro; Mori, Yasuyuki; Ohashi, Kazuhiko

    2015-10-19

    Johne's disease (paratuberculosis) is a chronic enteritis in cattle that is caused by intracellular infection with Mycobacterium avium subsp. paratuberculosis. This infection is characterized by the functional exhaustion of T-cell responses to M. avium subsp. paratuberculosis antigens during late subclinical and clinical stages, presumably facilitating the persistence of this bacterium and the formation of clinical lesions. However, the mechanisms underlying T-cell exhaustion in Johne's disease are poorly understood. Thus, we performed expression and functional analyses of the immunoinhibitory molecules programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) and lymphocyte activation gene 3 (LAG-3)/major histocompatibility complex class II (MHC-II) in M. avium subsp. paratuberculosis-infected cattle during the late subclinical stage. Flow cytometric analyses revealed the upregulation of PD-1 and LAG-3 in T cells in infected animals, which suffered progressive suppression of interferon gamma (IFN-γ) responses to the M. avium subsp. paratuberculosis antigen. In addition, PD-L1 and MHC-II were expressed on macrophages from infected animals, consistent with PD-1 and LAG-3 pathways contributing to the suppression of IFN-γ responses during the subclinical stages of M. avium subsp. paratuberculosis infection. Furthermore, dual blockade of PD-L1 and LAG-3 enhanced M. avium subsp. paratuberculosis-specific IFN-γ responses in blood from infected animals, and in vitro LAG-3 blockade enhanced IFN-γ production from M. avium subsp. paratuberculosis-specific CD4(+) and CD8(+) T cells. Taken together, the present data indicate that M. avium subsp. paratuberculosis-specific T-cell exhaustion is in part mediated by PD-1/PD-L1 and LAG-3/MHC-II interactions and that LAG-3 is a molecular target for the control of M. avium subsp. paratuberculosis-specific T-cell responses.

  12. Bovine Immunoinhibitory Receptors Contribute to Suppression of Mycobacterium avium subsp. paratuberculosis-Specific T-Cell Responses

    PubMed Central

    Okagawa, Tomohiro; Konnai, Satoru; Nishimori, Asami; Ikebuchi, Ryoyo; Mizorogi, Seiko; Nagata, Reiko; Kawaji, Satoko; Tanaka, Shogo; Kagawa, Yumiko; Murata, Shiro; Mori, Yasuyuki

    2015-01-01

    Johne's disease (paratuberculosis) is a chronic enteritis in cattle that is caused by intracellular infection with Mycobacterium avium subsp. paratuberculosis. This infection is characterized by the functional exhaustion of T-cell responses to M. avium subsp. paratuberculosis antigens during late subclinical and clinical stages, presumably facilitating the persistence of this bacterium and the formation of clinical lesions. However, the mechanisms underlying T-cell exhaustion in Johne's disease are poorly understood. Thus, we performed expression and functional analyses of the immunoinhibitory molecules programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) and lymphocyte activation gene 3 (LAG-3)/major histocompatibility complex class II (MHC-II) in M. avium subsp. paratuberculosis-infected cattle during the late subclinical stage. Flow cytometric analyses revealed the upregulation of PD-1 and LAG-3 in T cells in infected animals, which suffered progressive suppression of interferon gamma (IFN-γ) responses to the M. avium subsp. paratuberculosis antigen. In addition, PD-L1 and MHC-II were expressed on macrophages from infected animals, consistent with PD-1 and LAG-3 pathways contributing to the suppression of IFN-γ responses during the subclinical stages of M. avium subsp. paratuberculosis infection. Furthermore, dual blockade of PD-L1 and LAG-3 enhanced M. avium subsp. paratuberculosis-specific IFN-γ responses in blood from infected animals, and in vitro LAG-3 blockade enhanced IFN-γ production from M. avium subsp. paratuberculosis-specific CD4+ and CD8+ T cells. Taken together, the present data indicate that M. avium subsp. paratuberculosis-specific T-cell exhaustion is in part mediated by PD-1/PD-L1 and LAG-3/MHC-II interactions and that LAG-3 is a molecular target for the control of M. avium subsp. paratuberculosis-specific T-cell responses. PMID:26483406

  13. Complex Glycan Catabolism by the Human Gut Microbiota: The Bacteroidetes Sus-like Paradigm*

    PubMed Central

    Martens, Eric C.; Koropatkin, Nicole M.; Smith, Thomas J.; Gordon, Jeffrey I.

    2009-01-01

    Trillions of microbes inhabit the distal gut of adult humans. They have evolved to compete efficiently for nutrients, including a wide array of chemically diverse, complex glycans present in our diets, secreted by our intestinal mucosa, and displayed on the surfaces of other gut microbes. Here, we review how members of the Bacteroidetes, one of two dominant gut-associated bacterial phyla, process complex glycans using a series of similarly patterned, cell envelope-associated multiprotein systems. These systems provide insights into how gut, as well as terrestrial and aquatic, Bacteroidetes survive in highly competitive ecosystems. PMID:19553672

  14. Iron Acquisition in Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Wang, Joyce; Moolji, Jalal; Dufort, Alex; Staffa, Alfredo; Domenech, Pilar; Reed, Michael B.

    2015-01-01

    ABSTRACT Mycobacterium avium subsp. paratuberculosis is a host-adapted pathogen that evolved from the environmental bacterium M. avium subsp. hominissuis through gene loss and gene acquisition. Growth of M. avium subsp. paratuberculosis in the laboratory is enhanced by supplementation of the media with the iron-binding siderophore mycobactin J. Here we examined the production of mycobactins by related organisms and searched for an alternative iron uptake system in M. avium subsp. paratuberculosis. Through thin-layer chromatography and radiolabeled iron-uptake studies, we showed that M. avium subsp. paratuberculosis is impaired for both mycobactin synthesis and iron acquisition. Consistent with these observations, we identified several mutations, including deletions, in M. avium subsp. paratuberculosis genes coding for mycobactin synthesis. Using a transposon-mediated mutagenesis screen conditional on growth without myobactin, we identified a potential mycobactin-independent iron uptake system on a M. avium subsp. paratuberculosis-specific genomic island, LSPP15. We obtained a transposon (Tn) mutant with a disruption in the LSPP15 gene MAP3776c for targeted study. The mutant manifests increased iron uptake as well as intracellular iron content, with genes downstream of the transposon insertion (MAP3775c to MAP3772c [MAP3775-2c]) upregulated as the result of a polar effect. As an independent confirmation, we observed the same iron uptake phenotypes by overexpressing MAP3775-2c in wild-type M. avium subsp. paratuberculosis. These data indicate that the horizontally acquired LSPP15 genes contribute to iron acquisition by M. avium subsp. paratuberculosis, potentially allowing the subsequent loss of siderophore production by this pathogen. IMPORTANCE Many microbes are able to scavenge iron from their surroundings by producing iron-chelating siderophores. One exception is Mycobacterium avium subsp. paratuberculosis, a fastidious, slow-growing animal pathogen whose growth

  15. Network, degeneracy and bow tie. Integrating paradigms and architectures to grasp the complexity of the immune system

    PubMed Central

    2010-01-01

    Recently, the network paradigm, an application of graph theory to biology, has proven to be a powerful approach to gaining insights into biological complexity, and has catalyzed the advancement of systems biology. In this perspective and focusing on the immune system, we propose here a more comprehensive view to go beyond the concept of network. We start from the concept of degeneracy, one of the most prominent characteristic of biological complexity, defined as the ability of structurally different elements to perform the same function, and we show that degeneracy is highly intertwined with another recently-proposed organizational principle, i.e. 'bow tie architecture'. The simultaneous consideration of concepts such as degeneracy, bow tie architecture and network results in a powerful new interpretative tool that takes into account the constructive role of noise (stochastic fluctuations) and is able to grasp the major characteristics of biological complexity, i.e. the capacity to turn an apparently chaotic and highly dynamic set of signals into functional information. PMID:20701759

  16. Laser chimeras as a paradigm for multistable patterns in complex systems

    PubMed Central

    Larger, Laurent; Penkovsky, Bogdan; Maistrenko, Yuri

    2015-01-01

    A chimera state is a rich and fascinating class of self-organized solutions developed in high-dimensional networks. Necessary features of the network for the emergence of such complex but structured motions are non-local and symmetry breaking coupling. An accurate understanding of chimera states is expected to bring important insights on deterministic mechanism occurring in many structurally similar high-dimensional dynamics such as living systems, brain operation principles and even turbulence in hydrodynamics. Here we report on a powerful and highly controllable experiment based on an optoelectronic delayed feedback applied to a wavelength tuneable semiconductor laser, with which a wide variety of chimera patterns can be accurately investigated and interpreted. We uncover a cascade of higher-order chimeras as a pattern transition from N to N+1 clusters of chaoticity. Finally, we follow visually, as the gain increases, how chimera state is gradually destroyed on the way to apparent turbulence-like system behaviour. PMID:26169585

  17. Laser chimeras as a paradigm for multistable patterns in complex systems

    NASA Astrophysics Data System (ADS)

    Larger, Laurent; Penkovsky, Bogdan; Maistrenko, Yuri

    2015-07-01

    A chimera state is a rich and fascinating class of self-organized solutions developed in high-dimensional networks. Necessary features of the network for the emergence of such complex but structured motions are non-local and symmetry breaking coupling. An accurate understanding of chimera states is expected to bring important insights on deterministic mechanism occurring in many structurally similar high-dimensional dynamics such as living systems, brain operation principles and even turbulence in hydrodynamics. Here we report on a powerful and highly controllable experiment based on an optoelectronic delayed feedback applied to a wavelength tuneable semiconductor laser, with which a wide variety of chimera patterns can be accurately investigated and interpreted. We uncover a cascade of higher-order chimeras as a pattern transition from N to N+1 clusters of chaoticity. Finally, we follow visually, as the gain increases, how chimera state is gradually destroyed on the way to apparent turbulence-like system behaviour.

  18. Genomics and Machine Learning for Taxonomy Consensus: The Mycobacterium tuberculosis Complex Paradigm.

    PubMed

    Azé, Jérôme; Sola, Christophe; Zhang, Jian; Lafosse-Marin, Florian; Yasmin, Memona; Siddiqui, Rubina; Kremer, Kristin; van Soolingen, Dick; Refrégier, Guislaine

    2015-01-01

    Infra-species taxonomy is a prerequisite to compare features such as virulence in different pathogen lineages. Mycobacterium tuberculosis complex taxonomy has rapidly evolved in the last 20 years through intensive clinical isolation, advances in sequencing and in the description of fast-evolving loci (CRISPR and MIRU-VNTR). On-line tools to describe new isolates have been set up based on known diversity either on CRISPRs (also known as spoligotypes) or on MIRU-VNTR profiles. The underlying taxonomies are largely concordant but use different names and offer different depths. The objectives of this study were 1) to explicit the consensus that exists between the alternative taxonomies, and 2) to provide an on-line tool to ease classification of new isolates. Genotyping (24-VNTR, 43-spacers spoligotypes, IS6110-RFLP) was undertaken for 3,454 clinical isolates from the Netherlands (2004-2008). The resulting database was enlarged with African isolates to include most human tuberculosis diversity. Assignations were obtained using TB-Lineage, MIRU-VNTRPlus, SITVITWEB and an algorithm from Borile et al. By identifying the recurrent concordances between the alternative taxonomies, we proposed a consensus including 22 sublineages. Original and consensus assignations of the all isolates from the database were subsequently implemented into an ensemble learning approach based on Machine Learning tool Weka to derive a classification scheme. All assignations were reproduced with very good sensibilities and specificities. When applied to independent datasets, it was able to suggest new sublineages such as pseudo-Beijing. This Lineage Prediction tool, efficient on 15-MIRU, 24-VNTR and spoligotype data is available on the web interface "TBminer." Another section of this website helps summarizing key molecular epidemiological data, easing tuberculosis surveillance. Altogether, we successfully used Machine Learning on a large dataset to set up and make available the first consensual

  19. Genomics and Machine Learning for Taxonomy Consensus: The Mycobacterium tuberculosis Complex Paradigm

    PubMed Central

    Azé, Jérôme; Sola, Christophe; Zhang, Jian; Lafosse-Marin, Florian; Yasmin, Memona; Siddiqui, Rubina; Kremer, Kristin; van Soolingen, Dick; Refrégier, Guislaine

    2015-01-01

    Infra-species taxonomy is a prerequisite to compare features such as virulence in different pathogen lineages. Mycobacterium tuberculosis complex taxonomy has rapidly evolved in the last 20 years through intensive clinical isolation, advances in sequencing and in the description of fast-evolving loci (CRISPR and MIRU-VNTR). On-line tools to describe new isolates have been set up based on known diversity either on CRISPRs (also known as spoligotypes) or on MIRU-VNTR profiles. The underlying taxonomies are largely concordant but use different names and offer different depths. The objectives of this study were 1) to explicit the consensus that exists between the alternative taxonomies, and 2) to provide an on-line tool to ease classification of new isolates. Genotyping (24-VNTR, 43-spacers spoligotypes, IS6110-RFLP) was undertaken for 3,454 clinical isolates from the Netherlands (2004-2008). The resulting database was enlarged with African isolates to include most human tuberculosis diversity. Assignations were obtained using TB-Lineage, MIRU-VNTRPlus, SITVITWEB and an algorithm from Borile et al. By identifying the recurrent concordances between the alternative taxonomies, we proposed a consensus including 22 sublineages. Original and consensus assignations of the all isolates from the database were subsequently implemented into an ensemble learning approach based on Machine Learning tool Weka to derive a classification scheme. All assignations were reproduced with very good sensibilities and specificities. When applied to independent datasets, it was able to suggest new sublineages such as pseudo-Beijing. This Lineage Prediction tool, efficient on 15-MIRU, 24-VNTR and spoligotype data is available on the web interface “TBminer.” Another section of this website helps summarizing key molecular epidemiological data, easing tuberculosis surveillance. Altogether, we successfully used Machine Learning on a large dataset to set up and make available the first

  20. THE HUMAN MAJOR HISTOCOMPATIBILITY COMPLEX AS A PARADIGM IN GENOMICS RESEARCH

    PubMed Central

    Vandiedonck, Claire; Knight, Julian C

    2010-01-01

    Since its discovery more than 50 years ago, the human Major Histocompatibility Complex (MHC) on chromosome 6p21.3 has been at the forefront of human genetic research. Here, we review from a historical perspective the major advances in our understanding of the nature and consequences of genetic variation which have involved the MHC, as well as highlighting likely future directions. As a consequence of its particular genomic structure, its remarkable polymorphism and its early implication in numerous diseases, the MHC has been considered as a model region for genomics, being the first substantial region to be sequenced and establishing fundamental concepts of linkage disequilibrium, haplotypic structure and meiotic recombination. Recently, the MHC became the first genomic region to be entirely re-sequenced for common haplotypes, while studies mapping gene expression phenotypes across the genome have strongly implicated variation in the MHC. This review shows how the MHC continues to provide new insights and remains in the vanguard of contemporary research in human genomics. PMID:19468039

  1. Evolving paradigms in the treatment of relapsed/refractory multiple myeloma: increased options and increased complexity

    PubMed Central

    Cornell, R F; Kassim, A A

    2016-01-01

    The use of modern therapies such as thalidomide, bortezomib and lenalidomide coupled with upfront high-dose therapy and autologous stem cell transplant (ASCT) has resulted in improved survival in patients with newly diagnosed multiple myeloma (MM). However, patients with relapsed/refractory multiple myeloma (RRMM) often have poorer clinical outcomes and might benefit from novel therapeutic strategies. Emerging therapies, such as deacetylase inhibitors, monoclonal antibodies and new proteasome inhibitors, appear promising and may change the therapeutic landscape in RRMM. A limited number of studies has shown a benefit with salvage ASCT in patients with RRMM, although there remains ongoing debate about its timing and effectiveness. Improvement in transplant outcomes has re-ignited a debate on the timing and possible role for salvage ASCT and allogeneic stem cell transplant in RRMM. As the treatment options for management of patients with RRMM become increasingly complex, physicians must consider both disease- and patient-related factors in choosing the appropriate therapeutic approach, with the goal of improving efficacy while minimizing toxicity. PMID:26726946

  2. From link-prediction in brain connectomes and protein interactomes to the local-community-paradigm in complex networks

    PubMed Central

    Cannistraci, Carlo Vittorio; Alanis-Lobato, Gregorio; Ravasi, Timothy

    2013-01-01

    Growth and remodelling impact the network topology of complex systems, yet a general theory explaining how new links arise between existing nodes has been lacking, and little is known about the topological properties that facilitate link-prediction. Here we investigate the extent to which the connectivity evolution of a network might be predicted by mere topological features. We show how a link/community-based strategy triggers substantial prediction improvements because it accounts for the singular topology of several real networks organised in multiple local communities - a tendency here named local-community-paradigm (LCP). We observe that LCP networks are mainly formed by weak interactions and characterise heterogeneous and dynamic systems that use self-organisation as a major adaptation strategy. These systems seem designed for global delivery of information and processing via multiple local modules. Conversely, non-LCP networks have steady architectures formed by strong interactions, and seem designed for systems in which information/energy storage is crucial. PMID:23563395

  3. Syndromal complexity, paradigm shifts, and the future of validation research: comments on Nichols and Rogers, Sewell, Harrison, and Jordan.

    PubMed

    Weed, Nathan C

    2006-10-01

    In this comment, I address a number of the points raised in the reviews of the MMPI-2 Restructured Clinical (RC; Tellegen et al., 2003) Scales by Nichols (2006/this issue) and Rogers, Sewell, Harrison, and Jordan (2006/this issue), and I advocate for changes in assessment validation research. There is little evidence that the "syndromal complexity" Nichols ascribes to the original MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) Clinical Scales is worth preserving. Although their construction does not constitute the paradigm shift claimed by Rogers et al., the RC Scales are promising, psychometrically defensible measures of core features of the original MMPI-2 Clinical Scales. However, validation of inferences from multiscale inventories such as the MMPI-2 is limited at present by a disconnection between the integrative manner in which MMPI-2 profiles are interpreted and the scale-by-scale nature of most MMPI-2 validation studies. Q-sort procedures show promise for operationalizing integrated MMPI-2 interpretations, with both research and teaching applications.

  4. MYCOBACTERIUM AVIUM AND DRINKING WATER WHAT ARE THE CONNECTIONS?

    EPA Science Inventory

    Background: Human Mycobacterium avium infections are only known to be acquired from environmental sources such as water and soil. We compared M. avium isolates from clinical and drinking water sources using molecular tools. Methods: M. avium was isolated from water samples colle...

  5. Keap1 regulates inflammatory signaling in Mycobacterium avium-infected human macrophages.

    PubMed

    Awuh, Jane Atesoh; Haug, Markus; Mildenberger, Jennifer; Marstad, Anne; Do, Chau Phuc Ngoc; Louet, Claire; Stenvik, Jørgen; Steigedal, Magnus; Damås, Jan Kristian; Halaas, Øyvind; Flo, Trude Helen

    2015-08-04

    Several mechanisms are involved in controlling intracellular survival of pathogenic mycobacteria in host macrophages, but how these mechanisms are regulated remains poorly understood. We report a role for Kelch-like ECH-associated protein 1 (Keap1), an oxidative stress sensor, in regulating inflammation induced by infection with Mycobacterium avium in human primary macrophages. By using confocal microscopy, we found that Keap1 associated with mycobacterial phagosomes in a time-dependent manner, whereas siRNA-mediated knockdown of Keap1 increased M. avium-induced expression of inflammatory cytokines and type I interferons (IFNs). We show evidence of a mechanism whereby Keap1, as part of an E3 ubiquitin ligase complex with Cul3 and Rbx1, facilitates ubiquitination and degradation of IκB kinase (IKK)-β thus terminating IKK activity. Keap1 knockdown led to increased nuclear translocation of transcription factors NF-κB, IFN regulatory factor (IRF) 1, and IRF5 driving the expression of inflammatory cytokines and IFN-β. Furthermore, knockdown of other members of the Cul3 ubiquitin ligase complex also led to increased cytokine expression, further implicating this ligase complex in the regulation of the IKK family. Finally, increased inflammatory responses in Keap1-silenced cells contributed to decreased intracellular growth of M. avium in primary human macrophages that was reconstituted with inhibitors of IKKβ or TANK-binding kinase 1 (TBK1). Taken together, we propose that Keap1 acts as a negative regulator for the control of inflammatory signaling in M. avium-infected human primary macrophages. Although this might be important to avoid sustained or overwhelming inflammation, our data suggest that a negative consequence could be facilitated growth of pathogens like M. avium inside macrophages.

  6. Effects of Stop-Signal Probability in the Stop-Signal Paradigm: The N2/p3 Complex Further Validated

    ERIC Educational Resources Information Center

    Ramautar, J.R.; Kok, A.; Ridderinkhof, K.R.

    2004-01-01

    The aim of this study was to examine the effects of frequency of occurrence of stop signals in the stop-signal paradigm. Presenting stop signals less frequently resulted in faster reaction times to the go stimulus and a lower probability of inhibition. Also, go stimuli elicited larger and somewhat earlier P3 responses when stop signals occurred…

  7. Molecular Epidemiology of Mycobacterium avium subsp. paratuberculosis Isolates Recovered from Wild Animal Species

    PubMed Central

    Motiwala, Alifiya S.; Amonsin, Alongkorn; Strother, Megan; Manning, Elizabeth J. B.; Kapur, Vivek; Sreevatsan, Srinand

    2004-01-01

    Mycobacterial isolates were obtained by radiometric culture from 33 different species of captive or free-ranging animals (n = 106) and environmental sources (n = 3) from six geographic zones within the United States. The identities of all 109 isolates were confirmed by using mycobactin J dependence and characterization of five well-defined molecular markers, including two integration loci of IS900 (loci L1 and L9), one Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis)-specific sequence (locus 251), and one M. avium subsp. avium-specific marker (IS1245), as well as hsp65 and IS1311 restriction endonuclease analyses. Seventy-six acid-fast isolates were identified as M. paratuberculosis, 15 were identified as belonging to the M. avium-M. intracellulare complex (but not M. paratuberculosis), and the remaining 18 were identified as mycobacteria outside the M. avium-M. intracellulare complex. Fingerprinting by multiplex PCR for IS900 integration loci clustered 67 of the 76 M. paratuberculosis strains into a single clade (designated clade A18) and had a Simpson's diversity index (D) of 0.53. In contrast, sequence-based characterization of a recently identified M. paratuberculosis short sequence repeat (SSR) region enabled the differentiation of the M. paratuberculosis isolates in clade A18 into seven distinct alleles (D = 0.75). The analysis revealed eight subtypes among the 33 species of animals, suggesting the interspecies transmission of specific strains. Taken together, the results of our analyses demonstrate that SSR analysis enables the genetic characterization of M. paratuberculosis isolates from different host species and provide evidence for the host specificity of some M. paratuberculosis strains as well as sharing of strains between wild and domesticated animal species. PMID:15071028

  8. Diversity of Mycobacterium avium subsp. hominissuis mycobacteria causing lymphadenitis, France.

    PubMed

    Despierres, L; Cohen-Bacrie, S; Richet, H; Drancourt, M

    2012-07-01

    The knowledge of Mycobacterium avium complex (MAC) genotypes responsible for lymphadenitis is limited. We retrospectively characterized all of the MAC isolates made in our laboratory in the last 18 years by sequence-based identification and genotyping, and compared the clinical and laboratory data for lymphadenitis-associated and non-lymphadenitis-associated MAC isolates. Of 67 MAC-infected patients, 25 lymphadenitis patients were significantly younger than 42 non-lymphadenitis patients, while the male/female ratio did not significantly differ between the two groups. Cervical topography found in 76.5% of lymphadenitis patients was significantly more frequent in non-immunocompromised patients (p=0.04). M. avium subsp. hominissuis was identified in 53 patients (24 lymphadenitis, 29 non-lymphadenitis), M. colombiense in six patients (five non-lymphadenitis, one lymphadenitis), M. intracellulare in four non-lymphadenitis patients, and M. chimaera in three non-lymphadenitis patients, while negative controls remained negative. M. hominissuis was significantly associated with lymphadenitis (p=0.03). M. hominissuis isolates yielded 15 genotypes in 29 non-lymphadenitis isolates (molecular diversity, 0.622) versus 11 genotypes in 24 lymphadenitis isolates (molecular diversity, 0.578), demonstrating a non-significant lower diversity of M. hominissuis isolates cultured from lymphadenitis. The genotypes did not correlate with the clinical features. These data suggest the presence of several environmental reservoirs for M. hominissuis causing lymphadenitis in France.

  9. Disseminated Mycobacterium avium infection in a cat

    PubMed Central

    Barry, Maureen; Taylor, Judith; Woods, Paul

    2002-01-01

    A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture. PMID:12001504

  10. Disparate host immunity to Mycobacterium avium subsp. paratuberculosis antigens in calves inoculated with M. avium subsp. paratuberculosis, M. avium subsp. avium, M. kansasii and M. bovis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cross-reactivity of mycobacterial antigens in immune-based diagnostic assays has been a major concern and criticism of current tests for the detection of paratuberculosis. In the present study, host immune responses to antigen preparations of Mycobacterium avium subsp. paratuberculosis (MAP), consis...

  11. Iron-chelating compound from Mycobacterium avium.

    PubMed Central

    McCullough, W G; Merkal, R S

    1976-01-01

    A iron-chelating monohydroxamate was isolated from cultures of Mycobacterium avium grown on an iron-limiting medium. The hydroxyamate metabolite was characterized by chemical degradation and spectral measurements as L-alpha-asparaginyl-L-alpha-(N-hydroxy)-asparagine. PMID:185194

  12. Systems Analysis of Early Host Gene Expression Provides Clues for Transient Mycobacterium avium ssp avium vs. Persistent Mycobacterium avium ssp paratuberculosis Intestinal Infections

    PubMed Central

    Khare, Sangeeta; Drake, Kenneth L.; Lawhon, Sara D.; Nunes, Jairo E. S.; Figueiredo, Josely F.; Rossetti, Carlos A.; Gull, Tamara; Everts, Robin E.; Lewin, Harris. A.; Adams, Leslie Garry

    2016-01-01

    It has long been a quest in ruminants to understand how two very similar mycobacterial species, Mycobacterium avium ssp. paratuberculosis (MAP) and Mycobacterium avium ssp. avium (MAA) lead to either a chronic persistent infection or a rapid-transient infection, respectively. Here, we hypothesized that when the host immune response is activated by MAP or MAA, the outcome of the infection depends on the early activation of signaling molecules and host temporal gene expression. To test our hypothesis, ligated jejuno-ileal loops including Peyer’s patches in neonatal calves were inoculated with PBS, MAP, or MAA. A temporal analysis of the host transcriptome profile was conducted at several times post-infection (0.5, 1, 2, 4, 8 and 12 hours). When comparing the transcriptional responses of calves infected with the MAA versus MAP, discordant patterns of mucosal expression were clearly evident, and the numbers of unique transcripts altered were moderately less for MAA-infected tissue than were mucosal tissues infected with the MAP. To interpret these complex data, changes in the gene expression were further analyzed by dynamic Bayesian analysis. Bayesian network modeling identified mechanistic genes, gene-to-gene relationships, pathways and Gene Ontologies (GO) biological processes that are involved in specific cell activation during infection. MAP and MAA had significant different pathway perturbation at 0.5 and 12 hours post inoculation. Inverse processes were observed between MAP and MAA response for epithelial cell proliferation, negative regulation of chemotaxis, cell-cell adhesion mediated by integrin and regulation of cytokine-mediated signaling. MAP inoculated tissue had significantly lower expression of phagocytosis receptors such as mannose receptor and complement receptors. This study reveals that perturbation of genes and cellular pathways during MAP infection resulted in host evasion by mucosal membrane barrier weakening to access entry in the ileum

  13. Infants with complex congenital heart diseases show poor short-term memory in the mobile paradigm at 3 months of age.

    PubMed

    Chen, Chao-Ying; Harrison, Tondi; Heathcock, Jill

    2015-08-01

    The purpose of this study was to examine learning, short-term memory and general development including cognitive, motor, and language domains in infants with Complex Congenital Heart Defects (CCDH). Ten infants with CCHD (4 males, 6 females) and 14 infants with typical development (TD) were examined at 3 months of age. The mobile paradigm, where an infant's leg is tethered to an overhead mobile, was used to evaluate learning and short-term memory. The Bayley Scales of Infant Development 3rd edition (Bayley-III) was used to evaluate general development in cognitive, motor, and language domains. Infants with CCHD and infants with TD both showed learning with significant increase in kicking rate (p<0.001) across periods of the mobile paradigm, but only infants with TD demonstrated short-term memory (p=0.017) in the mobile paradigm. There were no differences on cognitive, motor, and language development between infants with CCHD and infants with TD on the Bayley-III. Early assessment is necessary to guide targeted treatment in infants with CCHD. One-time assessment may fail to detect potential cognitive impairments during early infancy in infants with CCHD. Supportive intervention programs for infants with CCHD that focuses on enhancing short-term memory are recommended.

  14. Mycobacterium avium infection in mice is associated with time-related expression of Th1 and Th2 CD4+ T-lymphocyte response.

    PubMed Central

    Azouaou, N; Petrofsky, M; Young, L S; Bermudez, L E

    1997-01-01

    Disseminated infection caused by organisms of Mycobacterium avium complex is common in acquired immune deficiency syndrome (AIDS) patients. M. avium is an intracellular bacterium that multiplies within macrophages. We examined the effect of M. avium infection on the T-helper cell response in C57/BL/6 black mice. At weekly intervals, CD4+ T-cells were isolated from spleens and lines were created. T-cell lines were exposed to sonicated M. avium in the presence of feeder cells and macrophages and the supernatant were collected to measure the concentrations of interferon-gamma (IFN-gamma and interleukin-10 (IL-10). Production of IFN-gamma in CD4+ T-cells obtained from uninfected mice did not vary significantly during the 5 weeks. Levels of IFN-gamma produced by T-cell lines of infected mice were similar to the control mice during the first 2 weeks but significantly reduced (approximately 30 ng/ml) thereafter. In contrast, production of IL-10 by T-cell lines of infected mice was in a range of 190 to 342 pg/ml in weeks 1, 2 and 3, but increased to an average of 1300 pg/ml at weeks 4 and 5. Pre-immunized mice, when infected with M. avium strain 101, showed a different profile of T-cell cytokines, with high IFN-gamma and low IL-10 production. Proteins purified from a number of disease-associated (D-A) and non-D-A strains of M. avium were tested for the ability to induce IL-10. 65,000 MW and 60,000 MW proteins of M. avium induced significantly more IL-10 than 45,000 MW, 33,000 MW and 27,000 MW proteins. These results showed that M. avium predominantly stimulates either Th1 or Th2 T-helper cells according to the phase of the infection. PMID:9301531

  15. Immunization with a DNA Vaccine Cocktail Induces a Th1 Response and Protects Mice Against Mycobacterium avium subsp. paratuberculosis Challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several novel antigens of Mycobacterium avium subsp. paratuberculosis have been studied as vaccine components and their immunogenicity has been evaluated. Previously, we reported that 85 antigen complex (85A, 85B, and 85C), superoxide dismutase (SOD), and 35kDa protein could induce significant lymph...

  16. Identification of Two Novel Mycobacterium avium Allelic Variants in Pig and Human Isolates from Brazil by PCR-Restriction Enzyme Analysis

    PubMed Central

    Leão, Sylvia Cardoso; Briones, Marcelo R. S.; Sircili, Marcelo Palma; Balian, Simone Carvalho; Mores, Nelson; Ferreira-Neto, José Soares

    1999-01-01

    Mycobacterium avium complex (MAC) is composed of environmental mycobacteria found widely in soil, water, and aerosols that can cause disease in animals and humans, especially disseminated infections in AIDS patients. MAC consists of two closely related species, M. avium and M. intracellulare, and may also include other, less-defined groups. The precise differentiation of MAC species is a fundamental step in epidemiological studies and for the evaluation of possible reservoirs for MAC infection in humans and animals. In this study, which included 111 pig and 26 clinical MAC isolates, two novel allelic M. avium PCR-restriction enzyme analysis (PRA) variants were identified, differing from the M. avium PRA prototype in the HaeIII digestion pattern. Mutations in HaeIII sites were confirmed by DNA sequencing. Identification of these isolates as M. avium was confirmed by PCR with DT1-DT6 and IS1245 primers, nucleic acid hybridization with the AccuProbe system, 16S ribosomal DNA sequencing, and biochemical tests. The characterization of M. avium PRA variants can be useful in the elucidation of factors involved in mycobacterial virulence and routes of infection and also has diagnostic significance, since they can be misidentified as M. simiae II and M. kansasii I if the PRA method is used in the clinical laboratory for identification of mycobacteria. PMID:10405407

  17. Experimental inoculation of BFDV-positive budgerigars (Melopsittacus undulatus) with two Mycobacterium avium subsp. avium isolates.

    PubMed

    Ledwoń, Aleksandra; Sapierzyński, Rafał; Augustynowicz-Kopeć, Ewa; Szeleszczuk, Piotr; Kozak, Marcin

    2014-01-01

    Beak and feather disease virus- (BFDV-) positive (naturally infected) but clinically healthy budgerigars (Melopsittacus undulatus) were inoculated with two isolates of Mycobacterium avium subsp. avium isolated from naturally infected golden pheasant (Chrysolophus pictus) and peafowl (Pavo cristatus). During a period of more than two months after inoculation, samples of cloacal and crop swabs, faeces, and blood were obtained for BFDV and Mycobacterium avium testing with PCR. Birds were euthanized nine weeks after inoculation. All infected budgerigars developed signs typical of mycobacteriosis, but more advanced clinical and pathological changes were visible in the group infected with the pheasant isolate. Only a few cloacal and crop swab samples were positive for Mycobacterium avium subsp. avium despite advanced pathological changes in the internal organs. In the groups infected with mycobacterium isolates the frequency of BFDV-positive samples was higher than in the control group. In the infected groups the frequency of BFDV was substantially higher in the cloacal swabs of birds inoculated with the pheasant isolate than in the peafowl-isolate-infected group.

  18. Experimental Inoculation of BFDV-Positive Budgerigars (Melopsittacus undulatus) with Two Mycobacterium avium subsp. avium Isolates

    PubMed Central

    Sapierzyński, Rafał; Szeleszczuk, Piotr

    2014-01-01

    Beak and feather disease virus- (BFDV-) positive (naturally infected) but clinically healthy budgerigars (Melopsittacus undulatus) were inoculated with two isolates of Mycobacterium avium subsp. avium isolated from naturally infected golden pheasant (Chrysolophus pictus) and peafowl (Pavo cristatus). During a period of more than two months after inoculation, samples of cloacal and crop swabs, faeces, and blood were obtained for BFDV and Mycobacterium avium testing with PCR. Birds were euthanized nine weeks after inoculation. All infected budgerigars developed signs typical of mycobacteriosis, but more advanced clinical and pathological changes were visible in the group infected with the pheasant isolate. Only a few cloacal and crop swab samples were positive for Mycobacterium avium subsp. avium despite advanced pathological changes in the internal organs. In the groups infected with mycobacterium isolates the frequency of BFDV-positive samples was higher than in the control group. In the infected groups the frequency of BFDV was substantially higher in the cloacal swabs of birds inoculated with the pheasant isolate than in the peafowl-isolate-infected group. PMID:24738057

  19. Mycobacterium avium subsp. avium found in raptors exposed to infected domestic fowl.

    PubMed

    Kriz, Petr; Kaevska, Marija; Bartejsova, Iva; Pavlik, Ivo

    2013-09-01

    We report a case of a falcon breeding facility, where raptors (both diurnal and nocturnal) were raised in contact with domestic fowl (Gallus gallus f. domesticus) infected by Mycobacterium avium subsp. avium. Fecal and environmental samples from 20 raptors and four common ravens (Corvus corax) were collected. Mycobacterium a. avium DNA was detected in feces of four raptors (bald eagle [Haliaeetus leucocephalus], eagle owl [Bubo bubo], barn owl [Tyto alba], and little owl [Athene noctua]) using triplex quantitative real-time PCR. As both the flock of domestic fowl and one of the infected raptors had the same origin (zoological collection), they might have had a common source of colonization/infection. However, the detection of M. a. avium in feces of three other raptors may point at transmission of the agent between the birds in the facility. Contact of raptors with domestic fowl infected by M. a. avium may pose a risk for transmission of the infection for them; however, raptors from the falcon breeding facility seemed to be relatively resistant to the infection.

  20. Loci of Mycobacterium avium ser2 gene cluster and their functions.

    PubMed Central

    Mills, J A; McNeil, M R; Belisle, J T; Jacobs, W R; Brennan, P J

    1994-01-01

    The highly antigenic glycopeptidolipids present on the surface of members of the Mycobacterium avium complex serve to distinguish these bacteria from all others and to define the various serovars that compose this complex. Previously, the genes responsible for the biosynthesis of the disaccharide hapten [2,3-di-O-methyl-alpha-L-fucopyranosyl-(1-->3)-alpha-L-rhamnopyranose] of serovar 2 of the M. avium complex were isolated, localized to a contiguous 22- to 27-kb fragment of the M. avium genome, and designated the ser2 gene cluster (J. T. Belisle, L. Pascopella, J. M. Inamine, P. J. Brennan, and W. R. Jacobs, Jr., J. Bacteriol. 173:6991-6997, 1991). In the present study, transposon saturation mutagenesis was used to map the specific genetic loci within the ser2 gene cluster required for expression of this disaccharide. Four essential loci, termed ser2A, -B, -C, and -D, constituting a total of 5.7 kb within the ser2 gene cluster, were defined. The ser2B and ser2D loci encode the methyltransferases required to methylate the fucose at the 3 and 2 positions, respectively. The rhamnosyltransferase was encoded by ser2A, whereas either ser2C or ser2D encoded the fucosyltransferase. The ser2C and ser2D loci are also apparently involved in the de novo synthesis of fucose. Isolation of the truncated versions of the hapten induced by the transposon insertions provides genetic evidence that the glycopeptidolipids of M. avium serovar 2 are synthesized by an initial transfer of the rhamnose unit to the peptide core followed by fucose and finally O methylation of the fucosyl unit. PMID:8050992

  1. Genetic IS901 RFLP diversity among Mycobacterium avium subsp. avium isolates from four pheasant flocks.

    PubMed

    Moravkova, Monika; Lamka, Jiri; Slany, Michal; Pavlik, Ivo

    2013-01-01

    IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four pheasant farms was performed. Using this method, six different IS901 RFLP types (E, F, G, M, Q, and V) were identified. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles observed in the present study indicate MAA transmission between pheasants and goshawks in the same locality. In two flocks, different pheasants within a flock as well as in various organs of five individual pheasants were found to have two distinct IS901 RFLP profiles.

  2. Bacteriocin from Honeybee Beebread Enterococcus avium, Active against Listeria monocytogenes

    PubMed Central

    Audisio, M. Carina; Terzolo, Horacio R.; Apella, María C.

    2005-01-01

    Enterococcus avium isolated from Apis mellifera beebread produces a thermoresistant bacteriocin with a strain-dependent inhibitory effect on Listeria and without effect on gram-negative bacteria. The bacteriocin appeared to be a polypeptide of about 6 kDa. Genetic analyses revealed no extrachromosomal material in E. avium. PMID:15933045

  3. Identification of Mycobacterium avium subsp. hominissuis Isolated From Drinking Water

    EPA Science Inventory

    Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...

  4. Formulation of indomethacin emulsion using biopolymer of Prunus avium.

    PubMed

    Verma, Shivangi; Dabral, Prashant; Rana, Vinod; Upadhaya, Kumud; Bhardwaj

    2012-03-01

    The aim of the investigation was to formulate Indomethacin Emulsion using Bio-polymer as Emulsifier. Different batches of emulsions were prepared by varying concentration of biopolymer prunus avium. Based evaluation of the prepared polymers, a conclusion can be drawn that in the Prunus avium bio-material can serve as a promising film forming agent for formulating various drug.

  5. Avian mycobacteriosis caused by Mycobacterium avium subspecies avium in four ornamental birds and in vitro drug sensitivity testing of isolates.

    PubMed

    Stepień-Pyśniak, Dagmara; Puk, Krzysztof; Guz, Leszek; Wawrzyniak, Agata; Marek, Agnieszka; Kosikowska, Urszula

    2016-01-01

    Avian tuberculosis, one of the most important diseases affecting various species of birds, is most often caused by Mycobacterium (M.) avium. This report describes cases of M. avium subsp. avium (MAA) infection in a white-crested Holland dwarf rooster, a male and a female golden pheasant and a male peacock. We also investigated the prevalence of mycobacteria in 60 other birds and 40 alpacas. Tissue samples of necropsied birds were cultured for mycobacteria. From non-necropsied 60 other birds and alpacas only faecal samples were collected. Clinical signs in the affected white-crested Holland cock included gradual loss of body weight and hoarse attempts at crowing during its last 3 weeks, with a dramatic loss of body condition and depression over the final week. Only slight weakening was observed in the peacock just before its death, and the golden pheasants died suddenly. Diagnosis was confirmed by microbiological, molecular and pathological results. Mycobacterium avium subsp. avium strains were isolated from the internal organs of the affected birds. Only one faecal sample from 60 other birds was culture- and PCR-positive for M. avium subsp. avium, while another one was only PCR-positive for M. chelonae. We did not isolate any Mycobacterium spp. from faecal samples of alpacas and all of them were PCR-negative. All 18 isolated M. avium strains were resistant to rifampicin, isoniazid, ethambutol, ethionamide, capreomycin and ofloxacin, and susceptible to cycloserine and streptomycin.

  6. Chemotaxis in Densely Populated Tissue Determines Germinal Center Anatomy and Cell Motility: A New Paradigm for the Development of Complex Tissues

    PubMed Central

    Hawkins, Jared B.; Jones, Mark T.; Plassmann, Paul E.; Thorley-Lawson, David A.

    2011-01-01

    Germinal centers (GCs) are complex dynamic structures that form within lymph nodes as an essential process in the humoral immune response. They represent a paradigm for studying the regulation of cell movement in the development of complex anatomical structures. We have developed a simulation of a modified cyclic re-entry model of GC dynamics which successfully employs chemotaxis to recapitulate the anatomy of the primary follicle and the development of a mature GC, including correctly structured mantle, dark and light zones. We then show that correct single cell movement dynamics (including persistent random walk and inter-zonal crossing) arise from this simulation as purely emergent properties. The major insight of our study is that chemotaxis can only achieve this when constrained by the known biological properties that cells are incompressible, exist in a densely packed environment, and must therefore compete for space. It is this interplay of chemotaxis and competition for limited space that generates all the complex and biologically accurate behaviors described here. Thus, from a single simple mechanism that is well documented in the biological literature, we can explain both higher level structure and single cell movement behaviors. To our knowledge this is the first GC model that is able to recapitulate both correctly detailed anatomy and single cell movement. This mechanism may have wide application for modeling other biological systems where cells undergo complex patterns of movement to produce defined anatomical structures with sharp tissue boundaries. PMID:22145018

  7. Apa antigen of Mycobacterium avium subsp. paratuberculosis as a target for species-specific immunodetection of the bacteria in infected tissues of cattle with paratuberculosis.

    PubMed

    Souza, Giliane S; Rodrigues, Ana Bárbara F; Gioffré, Andrea; Romano, Maria I; Carvalho, Eulógio C Q; Ventura, Thatiana L B; Lasunskaia, Elena B

    2011-09-15

    Comparative genomics of Mycobacterium spp. have revealed conservative genes and respective proteins differently expressed in mycobacteria that could be used as targets for the species-specific immunodiagnostics. The alanine and proline-rich antigen Apa is a mycobacterial protein that present significant variability in primary sequence length and composition between members of M. avium and M. tuberculosis complexes. In this study, the recombinant Apa protein encoded by the MAP1569/ModD gene of M. avium subsp. paratuberculosis (Map) was used to generate a panel of monoclonal antibodies which were shown to recognize the most important veterinary pathogens of the M. avium complex, specifically Map and M. avium subsp. hominissuis, and which did not cross-react with M. bovis or M. tuberculosis. The produced antibodies were demonstrated to be a useful tool for the species-specific immunofluorescence or immunohistochemical detection of Map in experimentally infected cell cultures or intestinal tissues from cattle with bovine paratuberculosis and, additionally, they may be employed for the discrimination of pathogenic M. avium subspecies via Western blotting.

  8. Characterization of a Novel Plasmid, pMAH135, from Mycobacterium avium Subsp. hominissuis

    PubMed Central

    Uchiya, Kei-ichi; Takahashi, Hiroyasu; Nakagawa, Taku; Yagi, Tetsuya; Moriyama, Makoto; Inagaki, Takayuki; Ichikawa, Kazuya; Nikai, Toshiaki; Ogawa, Kenji

    2015-01-01

    Mycobacterium avium complex (MAC) causes mainly two types of disease. The first is disseminated disease in immunocompromised hosts, such as individuals infected by human immunodeficiency virus (HIV). The second is pulmonary disease in individuals without systemic immunosuppression, and the incidence of this type is increasing worldwide. M. avium subsp. hominissuis, a component of MAC, causes infection in pigs as well as in humans. Many aspects of the different modes of M. avium infection and its host specificity remain unclear. Here, we report the characteristics and complete sequence of a novel plasmid, designated pMAH135, derived from M. avium strain TH135 in an HIV-negative patient with pulmonary MAC disease. The pMAH135 plasmid consists of 194,711 nucleotides with an average G + C content of 66.5% and encodes 164 coding sequences (CDSs). This plasmid was unique in terms of its homology to other mycobacterial plasmids. Interestingly, it contains CDSs with sequence homology to mycobactin biosynthesis proteins and type VII secretion system-related proteins, which are involved in the pathogenicity of mycobacteria. It also contains putative conserved domains of the multidrug efflux transporter. Screening of isolates from humans and pigs for genes located on pMAH135 revealed that the detection rate of these genes was higher in clinical isolates from pulmonary MAC disease patients than in those from HIV-positive patients, whereas the genes were almost entirely absent in isolates from pigs. Moreover, variable number tandem repeats typing analysis showed that isolates carrying pMAH135 genes are grouped in a specific cluster. Collectively, the pMAH135 plasmid contains genes associated with M. avium’s pathogenicity and resistance to antimicrobial agents. The results of this study suggest that pMAH135 influence not only the pathological manifestations of MAC disease, but also the host specificity of MAC infection. PMID:25671431

  9. Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

    USGS Publications Warehouse

    Fullerton, Aimee H.; Torgersen, Christian; Lawler, Joshua J.; Faux, Russell N.; Steel, E. Ashley; Beechie, Timothy J.; Ebersole, Joseph L.; Leibowitz, Scott J.

    2015-01-01

    Prevailing theory suggests that stream temperature warms asymptotically in a downstream direction, beginning at the temperature of the source in the headwaters and leveling off downstream as it converges to match meteorological conditions. However, there have been few empirical examples of longitudinal patterns of temperature in large rivers due to a paucity of data. We constructed longitudinal thermal profiles (temperature versus distance) for 53 rivers in the Pacific Northwest (USA) using an extensive dataset of remotely sensed summertime river temperatures and classified each profile into one of five patterns of downstream warming: asymptotic (increasing then flattening), linear (increasing steadily), uniform (not changing), parabolic (increasing then decreasing), or complex (not fitting other classes). We evaluated (1) how frequently profiles warmed asymptotically downstream as expected, and (2) whether relationships between river temperature and common hydroclimatic variables differed by profile class. We found considerable diversity in profile shape, with 47% of rivers warming asymptotically, and 53% having alternative profile shapes. Water temperature did not warm substantially over the course of the river for coastal parabolic and uniform profiles, and for some linear and complex profiles. Profile classes showed no clear geographical trends. The degree of correlation between river temperature and hydroclimatic variables differed among profile classes, but there was overlap among classes. Water temperature in rivers with asymptotic or parabolic profiles was positively correlated with August air temperature, tributary temperature and velocity, and negatively correlated with elevation, August precipitation, gradient, and distance upstream. Conversely, associations were less apparent in rivers with linear, uniform, or complex profiles. Factors contributing to the unique shape of parabolic profiles differed for coastal and inland rivers, where downstream cooling

  10. Inactivation of Mycobacterium avium with monochloramine.

    PubMed

    Luh, Jeanne; Tong, Ning; Raskin, Lutgarde; Mariñas, Benito J

    2008-11-01

    Batch experiments were performed to study the inactivation kinetics of Mycobacterium avium in the presence of monochloramine at 5-30 degrees C, pH 6-10, and 0.30-42.3 mg Cl2/ L. For each temperature and pH investigated, limiting high and low inactivation rates were observed for high and low disinfectant concentrations, respectively, within the range investigated. The rate of inactivation transitioned from high to low over a relatively narrow range of intermediate monochloramine concentrations. The observed temperature dependence of inactivation was consistent with an Arrhenius expression with activation energies of 58.0 and 71.7 kJ/mol for the high and low concentration ranges, respectively. The rate of inactivation increased with decreasing pH, consistent with trends reported for the reaction of monochloramine with protein thiols. Experiments performed at pH approximately 3.5 showed that dichloramine was a weaker disinfectant than monochloramine, and that its contribution to the overall inactivation of M. avium with combined chlorine was negligible at pH 6-10. A kinetic model incorporating disinfectant concentration, temperature, and pH effects was used to illustrate that monochloramine efficiency to inactivate M. avium in water could vary broadly from adequate (e.g., 99.9% inactivation efficiency in 32 min at 5 mg Cl2/L, pH 6, 30 degrees C) to impractical (e.g., 99.9% inactivation efficiency in 9 d at 1 mg Cl2/L, pH 9, 5 degrees C).

  11. Hyper-longevity, a late-modern paradigm for understanding longevity, ageing and their complexities in Western developed globalised countries.

    PubMed

    Alzetta, Roberto; Cesario, Alfredo; Fini, Massimo

    2014-01-01

    If longevity is a biological and demographic indicator to determine human lifetime extension, hyper-longevity notion can represent a heuristic tool to better disentangle the complex bio-psycho-social implications of ageing and elderly in Western developed globalised countries. Departing from the assumption of a holistic approach to human condition understanding, it is possible to reveal the grounds and patterns of a multilayered and multidimensional structuring of longevity and ageing in our societies that would lead to a form of hyper-longevity. Socio-cultural processes, underlying hyper-longevity notion, rise the question of transition from modern/ latemodern societies to post-modern ones and it offers room for a cultural analysis of concepts, such as space time compression, digital capitalism, knowledge and mass information society. These are relevant ideas that can contribute to reshape and rethink the boundaries and traits of ageing experience in 21(st) century societies. To better catch the point emerging social category of Baby Boomers is presented and used to provide a concrete context related example on how hyper-longevity can better explain complex social evidences in many cultural respects and social domains. As a conclusive step some preliminary reflections, largely centered on the relation between Baby Boomers, hyper-longevity and bio-medical sciences are presented and discussed to provide a starting point for further future analyses within a trans and inter-disciplinary framework.

  12. Identification of Mycobacterium avium and Mycobacterium intracellulare isolated in Puerto Rico from clinical samples by the use of a non-radioactive DNA probe.

    PubMed

    García, M T; Peña, I; Zlotnik, H

    1994-06-01

    The Mycobacterium avium complex (MAC), especially M. avium, is an important opportunistic pathogen of AIDS patients in the United States. In Puerto Rico, the incidence of infections caused by MAC has not been determined. This is due, in part, to the difficulties associated to the microbiological identification of the microorganisms. In this work, a commercially available kit (AccuProbe, Gen-Probe, Inc., San Diego, CA) utilizing a DNA probe complementary to rRNA of M. avium and M. intracellulare was used to identify seventeen MAC strains and one unknown atypical mycobacterium recovered in culture in Puerto Rico from clinical samples. The results obtained revealed that M. avium was the predominant species recovered (83% of isolates tested). Only two cultures were identified as M. intracellulare. The unknown culture, which did not react with either probe, turned out to be M. gordonae. The probe tests not only are simple to perform, but provide cultural identification results in as little as two hours. This study, the first one of its kind in Puerto Rico, demonstrates that the nucleic acid probes for the cultural identification of M. avium and M. intracellulare offer the potential of providing a prompt diagnosis and much needed data on the epidemiology of MAC infections in Puerto Rico.

  13. Evaluation of quantitative polymerase chain reaction assays targeting Mycobacterium avium, M. intracellulare, and M. avium subspecies paratuberculosis in drinking water biofilms.

    PubMed

    Chern, Eunice C; King, Dawn; Haugland, Richard; Pfaller, Stacy

    2015-03-01

    Mycobacterium avium (MA), Mycobacterium intracellulare (MI), and Mycobacterium avium subsp. paratuberculosis (MAP) are difficult to culture due to their slow growing nature. A quantitative polymerase chain reaction (qPCR) method for the rapid detection of MA, MI, and MAP can be used to provide data supporting drinking water biofilms as potential sources of human exposure. The aim of this study was to characterize two qPCR assays targeting partial 16S rRNA gene sequences of MA and MI and use these assays, along with two previously reported MAP qPCR assays (IS900 and Target 251), to investigate Mycobacterium occurrence in kitchen faucet biofilms. MA and MI qPCR assays demonstrated 100% specificity and sensitivity when evaluated against 18 non-MA complex, 76 MA, and 17 MI isolates. Both assays detected approximately 1,000 cells from a diluted cell stock inoculated on a sampling swab 100% of the time. DNA analysis by qPCR indicated that 35.3, 56.9 and 11.8% of the 51 kitchen faucet biofilm samples collected contained MA, MI, and MAP, respectively. This study introduces novel qPCR assays designed to specifically detect MA and MI in biofilm. Results support the use of qPCR as an alternative to culture for detection and enumeration of MA, MI, and MAP in microbiologically complex samples.

  14. Oral traditions: a contextual framework for complex science concepts—laying the foundation for a paradigm of promise in rural science education

    NASA Astrophysics Data System (ADS)

    Avery, Leanne M.; Hains, Bryan J.

    2017-03-01

    The overarching goal of this paper is to bring a diverse educational context—rural sayings and oral traditions situated in ecological habitats—to light and emphasize that they need to be taken into consideration regarding twenty-first century science education. The rural sayings or tenets presented here are also considered alternative ways of learning and knowing that rural people (elders and children) acquire outside of school in rural places of home and habitat. Throughout this paper we explore the complex nature of rural sayings or tenets that have been shared by community elders and examine their historic scientific roots. In so doing, we uncover a wealth of information regarding the diverse rural sociocultural and ecological connections and the situated macro and micro-contexts from which these tenets arise. We argue for a preservation and educational revitalization of these tenets for current and future generations. We show how this knowledge both augments and differs from traditional western science and science curricula by illuminating the ways in which oral traditions are embedded in place, people, memory and culture. We close by presenting an alternative paradigm for science education that incorporates pluralism as a means to enrich current place-based pedagogies and practices. We suggest that in order to tackle the complex problems in this new age of the Anthropocene, revitalizing elders' wisdom as well as valuing rural children's diverse knowledge and the inherent connectivity to their habitats needs be cultivated and not expunged by the current trends that standardize learning. As stated in the call for this special issue, "rurality has a real positionality" and much can be learned from individual and unique rural contexts.

  15. Oral traditions: a contextual framework for complex science concepts—laying the foundation for a paradigm of promise in rural science education

    NASA Astrophysics Data System (ADS)

    Avery, Leanne M.; Hains, Bryan J.

    2016-08-01

    The overarching goal of this paper is to bring a diverse educational context—rural sayings and oral traditions situated in ecological habitats—to light and emphasize that they need to be taken into consideration regarding twenty-first century science education. The rural sayings or tenets presented here are also considered alternative ways of learning and knowing that rural people (elders and children) acquire outside of school in rural places of home and habitat. Throughout this paper we explore the complex nature of rural sayings or tenets that have been shared by community elders and examine their historic scientific roots. In so doing, we uncover a wealth of information regarding the diverse rural sociocultural and ecological connections and the situated macro and micro-contexts from which these tenets arise. We argue for a preservation and educational revitalization of these tenets for current and future generations. We show how this knowledge both augments and differs from traditional western science and science curricula by illuminating the ways in which oral traditions are embedded in place, people, memory and culture. We close by presenting an alternative paradigm for science education that incorporates pluralism as a means to enrich current place-based pedagogies and practices. We suggest that in order to tackle the complex problems in this new age of the Anthropocene, revitalizing elders' wisdom as well as valuing rural children's diverse knowledge and the inherent connectivity to their habitats needs be cultivated and not expunged by the current trends that standardize learning. As stated in the call for this special issue, "rurality has a real positionality" and much can be learned from individual and unique rural contexts.

  16. Mycobacterium avium subsp. paratuberculosis in Veterinary Medicine

    PubMed Central

    Harris, N. Beth; Barletta, Raúl G.

    2001-01-01

    Mycobacterium avium subsp. paratuberculosis (basonym M. paratuberculosis) is the etiologic agent of a severe gastroenteritis in ruminants known as Johne's disease. Economic losses to the cattle industry in the United States are staggering, reaching $1.5 billion annually. A potential pathogenic role in humans in the etiology of Crohn's disease is under investigation. In this article, we review the epidemiology, pathogenesis, diagnostics, and disease control measures of this important veterinary pathogen. We emphasize molecular genetic aspects including the description of markers used for strain identification, diagnostics, and phylogenetic analysis. Recent important advances in the development of animal models and genetic systems to study M. paratuberculosis virulence determinants are also discussed. We conclude with proposals for the applications of these models and recombinant technology to the development of diagnostic, control, and therapeutic measures. PMID:11432810

  17. A Gene Specific to Mycobacterium avium subsp. paratuberculosis, But Only at the Transcription-translation Level

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is no known antibody that detects M. avium subsp paratuberculosis and does not cross react with other M. avium subspecies. In the present study, a monoclonal antibody was identified from mice immunized with a cell membrane fraction of M. avium subsp paratuberculosis strain K-10. This antibod...

  18. Comparative Genomic Analysis of Mycobacterium avium subspecies Obtained from Multiple Host Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A comparative genomic approach was used to identify large sequence polymorphisms among Mycobacterium avium (M. avium) subspecies obtained from a variety of host animals. DNA microarrays were used as a platform for comparing mycobacterial isolates with the sequenced bovine isolate M. avium subsp. p...

  19. Evaluation of Subspecies-specific Proteins for the Diagnosis of Mycobacterium avium subspecies paratuberculosis Infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subspecies paratuberculosis (Map)-specific proteins (35) were identified by comparing the proteomes of Map isolates with those of the genetically similar subspecies IS901+ Mycobacterium avium subspecies avium or silvaticum. This approach identified subspecies-specific proteins in...

  20. TGF-β-Mediated Sustained ERK1/2 Activity Promotes the Inhibition of Intracellular Growth of Mycobacterium avium in Epithelioid Cells Surrogates

    PubMed Central

    L'Abbate, Carolina; Cipriano, Ivone; Pérez-Hurtado, Elizabeth Cristina; Leão, Sylvia Cardoso; Carneiro, Célia Regina Whitaker; Machado, Joel

    2011-01-01

    Transforming growth factor beta (TGF-β) has been implicated in the pathogenesis of several diseases including infection with intracellular pathogens such as the Mycobacterium avium complex. Infection of macrophages with M. avium induces TGF-β production and neutralization of this cytokine has been associated with decreased intracellular bacterial growth. We have previously demonstrated that epithelioid cell surrogates (ECs) derived from primary murine peritoneal macrophages through a process of differentiation induced by IL-4 overlap several features of epithelioid cells found in granulomas. In contrast to undifferentiated macrophages, ECs produce larger amounts of TGF-β and inhibit the intracellular growth of M. avium. Here we asked whether the levels of TGF-β produced by ECs are sufficient to induce a self-sustaining autocrine TGF-β signaling controlling mycobacterial replication in infected-cells. We showed that while exogenous addition of increased concentration of TGF-β to infected-macrophages counteracted M. avium replication, pharmacological blockage of TGF-β receptor kinase activity with SB-431542 augmented bacterial load in infected-ECs. Moreover, the levels of TGF-β produced by ECs correlated with high and sustained levels of ERK1/2 activity. Inhibition of ERK1/2 activity with U0126 increased M. avium replication in infected-cells, suggesting that modulation of intracellular bacterial growth is dependent on the activation of ERK1/2. Interestingly, blockage of TGF-β receptor kinase activity with SB-431542 in infected-ECs inhibited ERK1/2 activity, enhanced intracellular M. avium burden and these effects were followed by a severe decrease in TGF-β production. In summary, our findings indicate that the amplitude of TGF-β signaling coordinates the strength and duration of ERK1/2 activity that is determinant for the control of intracellular mycobacterial growth. PMID:21731758

  1. Polymerase chain reaction-restriction fragment length polymorphism of the rpoB gene for identification of Mycobacterium avium subsp. paratuberculosis and differentiation of Mycobacterium avium subspecies.

    PubMed

    Whang, Jake; Lee, Byung Soo; Choi, Go-Eun; Cho, Sang-Nae; Kil, Park Young; Collins, Michael T; Shin, Sung Jae

    2011-05-01

    Mycobacterial speciation by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis (PRA) of the rpoB gene was evaluated for identification of Mycobacterium avium subsp. paratuberculosis (MAP) and other Mycobacterium avium complex (MAC) members to the species or subspecies level by comparison with conventional methods including hsp65 sequencing, high-performance liquid chromatography, and PCR for accepted species- or subspecies-specific genomic targets. A total of 185 type and clinical mycobacterial strains from humans, animals, and environments were tested. A 360-bp PCR product was subsequently digested with MspI, HaeIII, and SmaI restriction enzymes. The PRA using SmaI restriction showed a unique digestion pattern for MAP distinguishing it from other MAC members and other Mycobacterium spp. Moreover, HaeIII and MspI restriction of the rpoB gene enabled MAC-species and -subspecies discrimination. The rpoB-PRA using SmaI or MspI and HaeIII restriction of the rpoB gene is a simple, convenient, and reliable confirmatory assay for simultaneous identification of MAP and other MAC members.

  2. Effects of Age on Measures of Complex Working Memory Span in the Beagle Dog (Canis familiaris) Using Two Versions of a Spatial List Learning Paradigm

    PubMed Central

    Tapp, P. Dwight; Siwak, Christina T.; Estrada, Jimena; Holowachuk, Daniel; Milgram, Norton W.

    2003-01-01

    The present study used two versions of a spatial list learning (SLL) paradigm to examine the effects of increased cognitive load on visuospatial working memory processes in young and old beagle dogs. In the first experiment, young, and a select group of old dogs were first presented with one item, then two, and then three, and were rewarded for responding to the novel position. The dogs were able to learn the task at short delays, but compared with young dogs, old dogs performed worse at delays of 10 sec, and could not reach longer delays. Analysis of errors indicated that memory was best for end items in the spatial list and that within sessions, the number of errors in later trials was greater than the number of errors in earlier trials. A second version of the task, a modified SLL (mSLL) was developed to control for the use of non-mnemonic strategies on the SLL task. In this version, the first two items were presented individually. Acquisition and maximal memory performance were better in the young relative to the old dogs. Similar to the original SLL design, memory for early list items was worse than memory for later list items in both young and old dogs. The within-session pattern of errors however, did not change from trial to trial on the mSLL. The present results suggest that multiple working memory processes are engaged during complex tests of visuospatial function and the neuroanatomical substrates controlling these processes are affected differentially by age in the beagle dog. PMID:12663753

  3. Toward new Drosophila paradigms.

    PubMed

    Andrioli, Luiz Paulo

    2012-08-01

    The fruit fly Drosophila melanogaster is a great model system in developmental biology studies and related disciplines. In a historical perspective, I focus on the formation of the Drosophila segmental body plan using a comparative approach. I highlight the evolutionary trend of increasing complexity of the molecular segmentation network in arthropods that resulted in an incredible degree of complexity at the gap gene level in derived Diptera. There is growing evidence that Drosophila is a highly derived insect, and we are still far from fully understanding the underlying evolutionary mechanisms that led to its complexity. In addition, recent data have altered how we view the transcriptional regulatory mechanisms that control segmentation in Drosophila. However, these observations are not all bad news for the field. Instead, they stimulate further study of segmentation in Drosophila and in other species as well. To me, these seemingly new Drosophila paradigms are very challenging ones.

  4. Chlorine, Chloramine, Chlorine Dioxide, and Ozone Susceptibility of Mycobacterium avium

    PubMed Central

    Taylor, Robert H.; Falkinham, Joseph O.; Norton, Cheryl D.; LeChevallier, Mark W.

    2000-01-01

    Environmental and patient isolates of Mycobacterium avium were resistant to chlorine, monochloramine, chlorine dioxide, and ozone. For chlorine, the product of the disinfectant concentration (in parts per million) and the time (in minutes) to 99.9% inactivation for five M. avium strains ranged from 51 to 204. Chlorine susceptibility of cells was the same in washed cultures containing aggregates and in reduced aggregate fractions lacking aggregates. Cells of the more slowly growing strains were more resistant to chlorine than were cells of the more rapidly growing strains. Water-grown cells were 10-fold more resistant than medium-grown cells. Disinfectant resistance may be one factor promoting the persistence of M. avium in drinking water. PMID:10742264

  5. Preservation of monocyte effector functions against Mycobacterium avium-M. intracellulare in patients with AIDS.

    PubMed Central

    Johnson, J L; Shiratsuchi, H; Toba, H; Ellner, J J

    1991-01-01

    Mycobacterium avium-M. intracellulare is a frequent cause of late disseminated infection in patients with AIDS. The ability of human peripheral blood monocytes to phagocytose and kill M. avium was examined in an in vitro model. Monocytes were obtained from 13 healthy volunteers and 11 patients with AIDS, three of whom had documented disseminated M. avium infection. Monocytes were precultured for 2 days before infection with two AIDS-associated and two non-AIDS-associated strains of M. avium. Uptake of M. avium as measured by counting intracellular acid-fast bacilli did not differ among healthy subjects, patients with AIDS, or patients with AIDS and previously documented disseminated M. avium infection. Intracellular growth of M. avium was examined by a CFU assay of cell lysates from M. avium-infected monocytes after 0, 4, and 7 days of culture. Intracellular growth inhibition of M. avium at 7 days after infection was comparable between patients with AIDS and healthy donors for all M. avium strains tested. The effects of the addition of recombinant gamma interferon on M. avium uptake and intracellular growth in monocytes also were studied. Pretreatment of monocytes with gamma interferon prior to infection suppressed monocyte phagocytosis of M. avium. Continuously coculturing of monocytes with gamma interferon after infection augmented killing of M. avium among both patients with AIDS and healthy controls for three of the four strains of M. avium tested. The magnitude of this effect, however, was variable from donor to donor and strain to strain. No significant differences were noted between the growth-inhibiting abilities of gamma-interferon-treated monocytes obtained from healthy volunteers and those obtained from patients with AIDS. PMID:1910011

  6. Cryopreservation of Prunus avium L. embryogenic tissues.

    PubMed

    Grenier-de March, Ghislaine; de Boucaud, Marie-Therese; Chmielarz, Pawel

    2005-01-01

    Embryogenic tissues from wild cherry (Prunus avium L.) were successfully cryopreserved by using a one-step freezing procedure. Cryoprotection consisted of a pretreatment on solid medium with increasing sucrose concentrations (0.25 M for 1 day, 0.5 M for 1 day, 0.75 M for 2 days, and 1.0 M for 3 days), followed by air desiccation to about 20 percent moisture content (fresh weight basis). This method was compared with a pretreatment on solid medium containing 5 percent DMSO and 2 percent proline, followed by immersion in a modified PVS2 cryoprotective solution. Pretreatment on solid medium with increasing concentrations of sucrose led to regrowth of frozen embryogenic tissues, and after 6 weeks of culture, growth was comparable to that of non-dehydrated and non-frozen tissues. By contrast, no regrowth was observed when embryogenic tissues were submitted to the solid/liquid pretreatment with DMSO/proline and a modified PVS2 solution.

  7. Rapid broth macrodilution method for determination of MICs for Mycobacterium avium isolates.

    PubMed Central

    Siddiqi, S H; Heifets, L B; Cynamon, M H; Hooper, N M; Laszlo, A; Libonati, J P; Lindholm-Levy, P J; Pearson, N

    1993-01-01

    A multicenter study was done to investigate the accuracy and reproducibility of a method for determining the MICs of antimicrobial agents against the Mycobacterium avium complex in 7H12 broth with the BACTEC system. In phase I, with eight drugs and 10 strains, intralaboratory reproducibility was 95.7 to 100%, allowing a 1-dilution difference upon repeat testing. The results of phase II testing with 41 additional strains were consistent with those obtained in phase I, with good interlaboratory reproducibility. The radiometric method was validated by sampling and plating of the same broth cultures and determining, by the number of CFU per milliliter, the lowest drug concentration that inhibited more than 99% of the initial bacterial population. Three test concentrations of each drug and the tentative interpretation of results are proposed. Radiometric MIC determination has the potential to become the method of choice for clinical microbiology laboratories and evaluation of new agents for the treatment of M. avium infections, both pulmonary and disseminated. Images PMID:8408551

  8. High-Density Lipoprotein Binds to Mycobacterium avium and Affects the Infection of THP-1 Macrophages

    PubMed Central

    Ichimura, Naoya; Sato, Megumi; Yoshimoto, Akira; Yano, Kouji; Ohkawa, Ryunosuke; Kasama, Takeshi

    2016-01-01

    High-density lipoprotein (HDL) is involved in innate immunity toward various infectious diseases. Concerning bacteria, HDL is known to bind to lipopolysaccharide (LPS) and to neutralize its physiological activity. On the other hand, cholesterol is known to play an important role in mycobacterial entry into host cells and in survival in the intracellular environment. However, the pathogenicity of Mycobacterium avium (M. avium) infection, which tends to increase worldwide, remains poorly studied. Here we report that HDL indicated a stronger interaction with M. avium than that with other Gram-negative bacteria containing abundant LPS. A binding of apolipoprotein (apo) A-I, the main protein component of HDL, with a specific lipid of M. avium might participate in this interaction. HDL did not have a direct bactericidal activity toward M. avium but attenuated the engulfment of M. avium by THP-1 macrophages. HDL also did not affect bacterial killing after ingestion of live M. avium by THP-1 macrophage. Furthermore, HDL strongly promoted the formation of lipid droplets in M. avium-infected THP-1 macrophages. These observations provide new insights into the relationship between M. avium infection and host lipoproteins, especially HDL. Thus, HDL may help M. avium to escape from host innate immunity. PMID:27516907

  9. Tuberculosis in Birds: Insights into the Mycobacterium avium Infections

    PubMed Central

    Dhama, Kuldeep; Mahendran, Mahesh; Tiwari, Ruchi; Dayal Singh, Shambhu; Kumar, Deepak; Singh, Shoorvir; Sawant, Pradeep Mahadev

    2011-01-01

    Tuberculosis, a List B disease of World Organization for Animal Health, caused by M. avium or M. genavense predominantly affects poultry and pet or captive birds. Clinical manifestations in birds include emaciation, depression and diarrhea along with marked atrophy of breast muscle. Unlike tuberculosis in animals and man, lesions in lungs are rare. Tubercular nodules can be seen in liver, spleen, intestine and bone marrow. Granulomatous lesion without calcification is a prominent feature. The disease is a rarity in organized poultry sector due to improved farm practices, but occurs in zoo aviaries. Molecular techniques like polymerase chain reaction combined with restriction fragment length polymorphism and gene probes aid in rapid identification and characterization of mycobacteria subspecies, and overcome disadvantages of conventional methods which are slow, labour intensive and may at times fail to produce precise results. M. avium subsp. avium with genotype IS901+ and IS1245+ causes infections in animals and human beings too. The bacterium causes sensitivity in cattle to the tuberculin test. The paper discusses in brief the M. avium infection in birds, its importance in a zoonotic perspective, and outlines conventional and novel strategies for its diagnosis, prevention and eradication in domestic/pet birds and humans alike. PMID:21776352

  10. Mechanisms involved in the intrinsic isoniazid resistance of Mycobacterium avium.

    PubMed

    Mdluli, K; Swanson, J; Fischer, E; Lee, R E; Barry, C E

    1998-03-01

    Isoniazid (INH), which acts by inhibiting mycolic acid biosynthesis, is very potent against the tuberculous mycobacteria. It is about 100-fold less effective against Mycobacterium avium. This difference has often been attributed to a decreased permeability of the cell wall. We measured the rate of conversion of radiolabelled INH to 4-pyridylmethanol by whole cells and cell-free extracts and estimated the permeability barrier imposed by the cell wall to INH influx in Mycobacterium tuberculosis and M. avium. There was no significant difference in the relative permeability to INH between these two species. However, the total conversion rate in M. tuberculosis was found to be four times greater. Examination of in vitro-generated mutants revealed that the major resistance mechanism for both species is loss of the catalase-peroxidase KatG. Analysis of lipid and protein biosynthetic profiles demonstrated that the molecular target of activated INH was identical for both species. M. avium, however, formed colonies at INH concentrations inhibitory for mycolic acid biosynthesis. These mycolate-deficient M. avium exhibited altered colony morphologies, modified cell wall ultrastructure and were 10-fold more sensitive to treatment with hydrophobic antibiotics, such as rifampin. These findings may significantly impact the design of new therapeutic regimens for the treatment of infections with atypical mycobacteria.

  11. First identification of Mycobacterium avium paratuberculosis sheep strain in Argentina.

    PubMed

    Travería, G E; Zumarraga, M; Etchechoury, I; Romano, M I; Cataldi, A; Pinedo, M F Alvarado; Pavlik, I; Pribylova, R; Romero, J R

    2013-01-01

    We here identified for the first time the presence of Mycobacterium avium paratuberculosis (MAP) sheep (S) strain in Argentina. IS900 polymerase chain reaction (PCR) was positive. The S strain was compared with MAP cattle (C) strains by using IS1311 PCR-restriction endonuclease analysis (PCR-REA), multiplex PCR and restriction fragment length polymorphism (RFLP) analysis.

  12. Cellular Interactions in Mycobacterium avium subsp. paratuberculosis Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study of host immune responses to Mycobacterium avium subsp. paratuberculosis (MAP) is complicated by a number of factors, including the protracted nature of the disease and the stealthy nature of the pathogen. Noted as one of the more fastidious mycobacteria, infection with MAP is often chara...

  13. Mycobacterium avium subsp. paratuberculosis infection, immunology and pathology of livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) infection in ruminants leads to a chronic and progressive enteric disease (Johne’s disease) that results in loss of intestinal function, poor body condition, and eventual death. Transmission is primarily through a fecal-oral route in neonates but con...

  14. Beyond desertification: New paradigms for dryland landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dryland desertification paradigm focuses on losses of ecosystem services accompanying transitions from grasslands to systems dominated by bare ground or woody plants unpalatable for domestic livestock. However, recent studies reveal complex transitions across a range of environmental conditions ...

  15. The Reception Learning Paradigm.

    ERIC Educational Resources Information Center

    Novak, Joseph D.

    This report suggests that research in education, as well as the design of instruction, can be importantly influenced by the paradigm that guides the work. The application of a paradigm to educational research is illustrated, and two paradigms (reception learning and discovery learning) are contrasted. Finally, it is suggested that all educational…

  16. Thermal Inactivation of Mycobacterium avium subsp. paratuberculosis in Artificially Contaminated Milk by Direct Steam Injection

    PubMed Central

    Butot, Sophie; Jagadeesan, Balamurugan; Bakker, Douwe; Donaghy, John

    2016-01-01

    ABSTRACT The efficiency of direct steam injection (DSI) at 105°C for 3 s to inactivate Mycobacterium avium subsp. paratuberculosis in milk at a pilot-plant scale was investigated. Milk samples were artificially contaminated with M. avium subsp. paratuberculosis and also with cow fecal material naturally infected with M. avium subsp. paratuberculosis. We also tested milk artificially contaminated with Mycobacterium smegmatis as a candidate surrogate to compare thermal inactivation between M. smegmatis and M. avium subsp. paratuberculosis. Following the DSI process, no viable M. avium subsp. paratuberculosis or M. smegmatis was recovered using culture methods for both strains. For pure M. avium subsp. paratuberculosis cultures, a minimum reduction of 5.6 log10 was achieved with DSI, and a minimum reduction of 5.7 log10 was found with M. smegmatis. The minimum log10 reduction for wild-type M. avium subsp. paratuberculosis naturally present in feces was 3.3. In addition, 44 dairy and nondairy powdered infant formula (PIF) ingredients used during the manufacturing process of PIF were tested for an alternate source for M. avium subsp. paratuberculosis and were found to be negative by quantitative PCR (qPCR). In conclusion, the results obtained from this study indicate that a >7-fold-log10 reduction of M. avium subsp. paratuberculosis in milk can be achieved with the applied DSI process. IMPORTANCE M. avium subsp. paratuberculosis is widespread in dairy herds in many countries. M. avium subsp. paratuberculosis is the causative agent of Johne's disease in cattle, and infected animals can directly or indirectly (i.e., fecal contamination) contaminate milk. Despite much research and debate, there is no conclusive evidence that M. avium subsp. paratuberculosis is a zoonotic bacterium, i.e., one that causes disease in humans. The presence of M. avium subsp. paratuberculosis or its DNA has been reported in dairy products, including pasteurized milk, cheese, and infant formula

  17. Utilization of Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS) to Identify environmental Strains of Mycobacterium Complex

    EPA Science Inventory

    Species within the Mycobacterium avium Complex (MAC) group are found to be both prevalent and persistent in drinking water distribution systems. The MAC is composed of two predominant species: M. avium and M. intracellulare. These species have the ability to survive drinking ...

  18. Inter- and Intra-subtype genotypic differences that differentiate Mycobacterium avium subspecies paratuberculosis strains

    PubMed Central

    2012-01-01

    Background Mycobacterium avium subspecies paratuberculosis (Map) is the aetiological agent of Johne’s disease or paratuberculosis and is included within the Mycobacterium avium complex (MAC). Map strains are of two major types often referred to as ‘Sheep’ or ‘S-type’ and ‘Cattle’ or ‘C-type’. With the advent of more discriminatory typing techniques it has been possible to further classify the S-type strains into two groups referred to as Type I and Type III. This study was undertaken to genotype a large panel of S-type small ruminant isolates from different hosts and geographical origins and to compare them with a large panel of well documented C-type isolates to assess the genetic diversity of these strain types. Methods used included Mycobacterial Interspersed Repetitive Units - Variable-Number Tandem Repeat analysis (MIRU-VNTR), analysis of Large Sequence Polymorphisms by PCR (LSP analysis), Single Nucleotide Polymorphism (SNP) analysis of gyr genes, Pulsed-Field Gel Electrophoresis (PFGE) and Restriction Fragment Length Polymorphism analysis coupled with hybridization to IS900 (IS900-RFLP) analysis. Results The presence of LSPA4 and absence of LSPA20 was confirmed in all 24 Map S-type strains analysed. SNPs within the gyr genes divided the S-type strains into types I and III. Twenty four PFGE multiplex profiles and eleven different IS900-RFLP profiles were identified among the S-type isolates, some of them not previously published. Both PFGE and IS900-RFLP segregated the S-type strains into types I and III and the results concurred with those of the gyr SNP analysis. Nine MIRU-VNTR genotypes were identified in these isolates. MIRU-VNTR analysis differentiated Map strains from other members of Mycobacterium avium Complex, and Map S-type from C-type but not type I from III. Pigmented Map isolates were found of type I or III. Conclusion This is the largest panel of S-type strains investigated to date. The S-type strains could be further divided

  19. Host responses to persistent Mycobacterium avium subspecies paratuberculosis infection in surgically isolated bovine ileal segments.

    PubMed

    Charavaryamath, Chandrashekhar; Gonzalez-Cano, Patricia; Fries, Patrick; Gomis, Susantha; Doig, Kimberley; Scruten, Erin; Potter, Andrew; Napper, Scott; Griebel, Philip J

    2013-02-01

    A lack of appropriate disease models has limited our understanding of the pathogenesis of persistent enteric infections with Mycobacterium avium subsp. paratuberculosis. A model was developed for the controlled delivery of a defined dose of M. avium subsp. paratuberculosis to surgically isolated ileal segments in newborn calves. The stable intestinal segments enabled the characterization of host responses to persistent M. avium subsp. paratuberculosis infections after a 9-month period, including an analysis of local mucosal immune responses relative to an adjacent uninfected intestinal compartment. M. avium subsp. paratuberculosis remained localized at the initial site of intestinal infection and was not detected by PCR in the mesenteric lymph node. M. avium subsp. paratuberculosis-specific T cell proliferative responses included both CD4 and γδ T cell receptor (γδTcR) T cell responses in the draining mesenteric lymph node. The levels of CD8(+) and γδTcR(+) T cells increased significantly (P < 0.05) in the lamina propria, and M. avium subsp. paratuberculosis-specific tumor necrosis factor alpha (TNF-α) and gamma interferon secretion by lamina propria leukocytes was also significantly (P < 0.05) increased. There was a significant (P < 0.05) accumulation of macrophages and dendritic cells (DCs) in the lamina propria, but the expression of mucosal toll-like receptors 1 through 10 was not significantly changed by M. avium subsp. paratuberculosis infection. In conclusion, surgically isolated ileal segments provided a model system for the establishment of a persistent and localized enteric M. avium subsp. paratuberculosis infection in cattle and facilitated the analysis of M. avium subsp. paratuberculosis-specific changes in mucosal leukocyte phenotype and function. The accumulation of DC subpopulations in the lamina propria suggests that further investigation of mucosal DCs may provide insight into host responses to M. avium subsp. paratuberculosis infection and

  20. Serologic tests for detecting antibodies against Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis in Eurasian wild boar (Sus scrofa scrofa).

    PubMed

    Boadella, Mariana; Lyashchenko, Konstantin; Greenwald, Reena; Esfandiari, Javan; Jaroso, Raquel; Carta, Tania; Garrido, Joseba M; Vicente, Joaquín; de la Fuente, José; Gortázar, Christian

    2011-01-01

    New tools to detect exposure of free-range Eurasian wild boar (Sus scrofa scrofa) to pathogenic mycobacteria would be valuable for improved disease surveillance and wildlife management. Two hundred sera from wild boar of known Mycobacterium bovis infection status were used to evaluate test suitability for the detection of antibodies against M. bovis and Mycobacterium avium subsp. paratuberculosis (or cross-reacting members of the M. avium complex). Two traditional enzyme-linked immunosorbent assays were evaluated using M. bovis purified protein derivative (bPPD) and paratuberculosis protoplasmatic antigen 3 (PPA3) as antigens, respectively, and a new point-of-care test format for bovine tuberculosis (bTB) that uses the innovative dual-path platform (DPP TB) test. The effect of individual factors (sex, age, lesions) on the diagnostic performance of the serologic tests was also determined. Although the DPP had a sensitivity of 89.6% and a specificity of 90.4%, for bPPD, the sensitivity was 79.2% and the specificity 100%. Both tests had a kappa agreement of 0.80. Sixty-five of 68 (95.6%) wild boar sera with antibodies against the PPA3 antigen corresponded to known M. bovis-infected wild boar. Significant differences were not observed in the bPPD and DPP readings among lesion categories or between age classes. A slight sex-related difference in sensitivity toward males in the DPP was found, but it was not detected in the bPPD enzyme-linked immunosorbent assay. The results support the use of antibody-based diagnostic tests for both large-scale and individual bTB testing of Eurasian wild boar and suggest that wild boar cannot be used as sentinels for infections caused by M. avium complex members.

  1. Intramacrophage growth of Mycobacterium avium during infection of mice.

    PubMed Central

    Frehel, C; de Chastellier, C; Offredo, C; Berche, P

    1991-01-01

    Growth of the virulent Mycobacterium avium strain TMC 724 in host tissues during persistent infection of mice was studied. Following intravenous infection of C57BL/6 mice, the kinetics of bacterial growth was biphasic in the spleen and liver, with a significant reduction of the multiplication rate after day 21 to 28 of infection. An electron-microscopic study of the liver and spleen of infected mice showed that the bacteria were strictly intracellular. They were observed within inflammatory macrophages populating granulomas disseminated in host tissues. The bacteria were confined to the phagosome compartment, and they were encapsulated. Phagosome-lysosome fusions were encountered, but the bacteria showed no visible signs of degradation and continued to multiply. These results are the first in vivo evidence that virulent M. avium multiplies exclusively intracellularly and that encapsulated bacteria resist the microbicidal mechanisms of macrophages inside the phagosomal compartment. Images PMID:2037382

  2. Linking metacommunity paradigms to spatial coexistence mechanisms.

    PubMed

    Shoemaker, Lauren G; Melbourne, Brett A

    2016-09-01

    Four metacommunity paradigms-usually called neutral, species sorting, mass effects, and patch dynamics, respectively-are widely used for empirical and theoretical studies of spatial community dynamics. The paradigm framework highlights key ecological mechanisms operating in metacommunities, such as dispersal limitation, competition-colonization tradeoffs, or species equivalencies. However, differences in coexistence mechanisms between the paradigms and in situations with combined influences of multiple paradigms are not well understood. Here, we create a common model for competitive metacommunities, with unique parameterizations for each metacommunity paradigm and for scenarios with multiple paradigms operating simultaneously. We derive analytical expressions for the strength of Chesson's spatial coexistence mechanisms and quantify these for each paradigm via simulation. For our model, fitness-density covariance, a concentration effect measuring the importance of intraspecific aggregation of individuals, is the dominant coexistence mechanism in all three niche-based metacommunity paradigms. Increased dispersal between patches erodes intraspecific aggregation, leading to lower coexistence strength in the mass effects paradigm compared to species sorting. Our analysis demonstrates the potential importance of aggregation of individuals (fitness-density covariance) over co-variation in abiotic environments and competition between species (the storage effect), as fitness-density covariance can be stronger than the storage effect and is the sole stabilizing mechanism in the patch dynamics paradigm. As expected, stable coexistence does not occur in the neutral paradigm, which requires species to be equal and emphasizes the role of stochasticity. We show that stochasticity also plays an important role in niche-structured metacommunities by altering coexistence strength. We conclude that Chesson's spatial coexistence mechanisms provide a flexible framework for comparing

  3. Mycobacterium avium-intracellulare: a rare cause of subacromial bursitis.

    PubMed

    Sinha, Raj; Tuckett, John; Hide, Geoff; Dildey, Petra; Karsandas, Alvin

    2015-01-01

    Septic subacromial bursitis is an uncommon disorder with only a few reported cases in the literature. The most common causative organism is Staphylococcus aureus. We report the case of a 61-year-old female with a septic subacromial bursitis where the causative organism was found to be Mycobacterium avium-intracellulare (MAI). The diagnosis was only made following a biopsy, and we use this case to highlight the importance of recognising the need to consider a biopsy and aspiration in atypical situations.

  4. Molecular Identification of Mycobacterium avium subsp. silvaticum by Duplex High-Resolution Melt Analysis and Subspecies-Specific Real-Time PCR

    PubMed Central

    Csivincsik, Ágnes; Dán, Ádám

    2015-01-01

    Accurate identification of mycobacterial species and subspecies is essential to evaluate their significance and to perform epidemiological studies. The subspecies of Mycobacterium avium have different attributes but coincide in their zoonotic potential. Our knowledge about M. avium subsp. silvaticum is limited, since its identification is uncertain. Mycobacterium avium subsp. avium and M. avium subsp. silvaticum can be discriminated from each other based only on phenotypic characteristics, as they have almost identical genome sequences. Here we describe the development of a diagnostic method which enables the molecular identification of M. avium subsp. silvaticum and discrimination from M. avium subsp. avium based on genomic differences in a duplex high-resolution melt and M. avium subsp. silvaticum-specific mismatch real-time PCR. The developed assay was tested on reference strains and 199 field isolates, which were analyzed by phenotypic methods previously. This assay not only identified all 63 M. avium subsp. silvaticum and 138 M. avium subsp. avium strains correctly but also enabled the detection of mixed M. avium subsp. avium-M. avium subsp. silvaticum cultures. This is the first time that such a large panel of strains has been analyzed, and we also report the first isolation of M. avium subsp. silvaticum from red fox, red deer, wild boar, cattle, and badger. This assay is reliable, rapid, simple, inexpensive, and robust. It eliminates the long-existing problem of ambiguous phenotypic identification and opens up the possibility for detailed and comprehensive strain studies. PMID:25740770

  5. Molecular identification of Mycobacterium avium subsp. silvaticum by duplex high-resolution melt analysis and subspecies-specific real-time PCR.

    PubMed

    Rónai, Zsuzsanna; Csivincsik, Ágnes; Dán, Ádám

    2015-05-01

    Accurate identification of mycobacterial species and subspecies is essential to evaluate their significance and to perform epidemiological studies. The subspecies of Mycobacterium avium have different attributes but coincide in their zoonotic potential. Our knowledge about M. avium subsp. silvaticum is limited, since its identification is uncertain. Mycobacterium avium subsp. avium and M. avium subsp. silvaticum can be discriminated from each other based only on phenotypic characteristics, as they have almost identical genome sequences. Here we describe the development of a diagnostic method which enables the molecular identification of M. avium subsp. silvaticum and discrimination from M. avium subsp. avium based on genomic differences in a duplex high-resolution melt and M. avium subsp. silvaticum-specific mismatch real-time PCR. The developed assay was tested on reference strains and 199 field isolates, which were analyzed by phenotypic methods previously. This assay not only identified all 63 M. avium subsp. silvaticum and 138 M. avium subsp. avium strains correctly but also enabled the detection of mixed M. avium subsp. avium-M. avium subsp. silvaticum cultures. This is the first time that such a large panel of strains has been analyzed, and we also report the first isolation of M. avium subsp. silvaticum from red fox, red deer, wild boar, cattle, and badger. This assay is reliable, rapid, simple, inexpensive, and robust. It eliminates the long-existing problem of ambiguous phenotypic identification and opens up the possibility for detailed and comprehensive strain studies.

  6. Effect of Prunus avium roots on river bank strong.

    PubMed

    Bibalani, Ghassem Habibi; Bazhrang, Zia; Mohsenifar, Hani; Shibaei, Naeime; Joodi, Lila

    2008-04-15

    A pulling effect by side roots is one way in which roots help to side in-plane strong of a little depth soil mass. In contrast to the effect of vertically-enlarge roots, whereby soil is strengthened by an increase in its shear strength, the pulling effect strengthens the soil by increasing the tensile strength of the rooted soil zone. To verify whether or not a pulling effect exists in the root system of Prunus avium in the Roudsar, North Iran and to study the importance and size of this effect, a direct in situ test was led at a site in the Chaboksar Forests. The results from the site showed that, in the surface soil (0-30 cm), Side roots can provide a pull force of up to 490-712 N (Newtons) over a vertical cross-section area of 20-50 cm2, or an enhance in the pulling stability of the rooted soil by about 48.1%. The test results suggest that, together with the Prunus avium vertical roots, which keep the little depth rooted soil zone to the deep and more stable soil mass, the side roots of the Prunus avium, with their pulling effect, are able to make less against little depth instability in the forest slopes, such as little depth slide, to a certain degree.

  7. Antigenic Profiles of Recombinant Proteins from Mycobacterium avium subsp paratuberculosis in Sheep with Johne's Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods to improve the ELISA test to detect Mycobacterium avium subsp paratuberculosis have been explored over several years. Previously, selected recombinant proteins of M. avium subspecies paratuberculosis were found to be immunogenic in cattle with Johne’s disease. In the present study, antibo...

  8. Complete genome sequence of Mycobacterium avium subsp. paratuberculosis, isolated from human breast milk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp paratuberculosis is the etiologic agent of Johne’s disease. We report the draft genome sequences of six M. avium subsp paratuberculosis isolates obtained from diverse hosts including bison, cattle and sheep. These sequences will deepen our understanding of host association ...

  9. Profiling Host Antibody Responses to Mycobacterium avium subspecies paratuberculosis Infection Using Protein Arrays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Along with the complete genome sequence of Mycobacterium avium subspecies paratuberculosis, technologies are now developed for the construction of protein arrays to detect the presence of antibodies against M. avium subsp paratuberculosis in host serum. The power of this approach is that it enable...

  10. Roles for Cell Wall Glycopeptidolipid in Surface Adherence and Planktonic Dispersal of Mycobacterium avium

    EPA Science Inventory

    The opportunistic pathogen Mycobacterium avium is a significant inhabitant of biofilms in drinking water distribution systems. M. avium expresses on its cell surface serovar-specific glycopeptidolipids (ssGPLs). Studies have implicated the core GPL in biofilm formation by M. aviu...

  11. An Integrative Paradigm

    ERIC Educational Resources Information Center

    Hammack, Phillip L.

    2005-01-01

    Through the application of life course theory to the study of sexual orientation, this paper specifies a new paradigm for research on human sexual orientation that seeks to reconcile divisions among biological, social science, and humanistic paradigms. Recognizing the historical, social, and cultural relativity of human development, this paradigm…

  12. Organizational Paradigm Shifts.

    ERIC Educational Resources Information Center

    National Association of College and University Business Officers, Washington, DC.

    This collection of essays explores a new paradigm of higher education. The first essay, "Beyond Re-engineering: Changing the Organizational Paradigm" (L. Edwin Coate), suggests a model of quality process management and a structure for managing organizational change. "Thinking About Consortia" (Mary Jo Maydew) discusses…

  13. The Investment Paradigm

    ERIC Educational Resources Information Center

    Perna, Mark C.

    2005-01-01

    Is marketing an expense or an investment? Most accountants will claim that marketing is an expense, and clearly that seems true when cutting the checks to fund these efforts. When it is done properly, marketing is the best investment. A key principle to Smart Marketing is the Investment Paradigm. The Investment Paradigm is understanding that every…

  14. The Generative Paradigm.

    ERIC Educational Resources Information Center

    Loynes, Chris

    2002-01-01

    The "algorithmic" model of outdoor experiential learning is based in military tradition and characterized by questionable scientific rationale, production line metaphor, and the notion of learning as marketable commodity. Alternatives are the moral paradigm; the ecological paradigm "friluftsliv"; and the emerging…

  15. Azithromycin Dose To Maximize Efficacy and Suppress Acquired Drug Resistance in Pulmonary Mycobacterium avium Disease

    PubMed Central

    Deshpande, Devyani; Pasipanodya, Jotam G.

    2016-01-01

    Mycobacterium avium complex is now the leading mycobacterial cause of chronic pneumonia in the United States. Macrolides and ethambutol form the backbone of the regimen used in the treatment of pulmonary disease. However, therapy outcomes remain poor, with microbial cure rates of 4% in cavitary disease. The treatment dose of azithromycin has mostly been borrowed from that used to treat other bacterial pneumonias; there are no formal dose-response studies in pulmonary M. avium disease and the optimal dose is unclear. We utilized population pharmacokinetics and pharmacokinetics/pharmacodynamics-derived azithromycin exposures associated with optimal microbial kill or resistance suppression to perform 10,000 patient Monte Carlo simulations of dose effect studies for daily azithromycin doses of 0.5 to 10 g. The currently recommended dose of 500 mg per day achieved the target exposures in 0% of patients. Exposures associated with optimal kill and resistance suppression were achieved in 87 and 54% of patients, respectively, only by the very high dose of 8 g per day. The azithromycin susceptibility breakpoint above which patients failed therapy on the very high doses of 8 g per day was an MIC of 16 mg/liter, suggesting a critical concentration of 32 mg/liter, which is 8-fold lower than the currently used susceptibility breakpoint of 256 mg/liter. If the standard dose of 500 mg a day were used, then the critical concentration would fall to 2 mg/liter, 128-fold lower than 256 mg/liter. The misclassification of resistant isolates as susceptible could explain the high failure rates of current doses. PMID:26810646

  16. A new paradigm and computational framework to estimate stop-signal reaction time distributions from the inhibition of complex motor sequences

    PubMed Central

    Teichert, Tobias; Ferrera, Vincent P.

    2015-01-01

    Inhibitory control is an important component of executive function that allows organisms to abort emerging behavioral plans or ongoing actions on the fly as new sensory information becomes available. Current models treat inhibitory control as a race between a Go- and a Stop process that may be mediated by partially distinct neural substrates, i.e., the direct and the hyper-direct pathway of the basal ganglia. The fact that finishing times of the Stop process (Stop-Signal Reaction Time, SSRT) cannot be observed directly has precluded a precise comparison of the functional properties that govern the initiation (GoRT) and inhibition (SSRT) of a motor response. To solve this problem, we modified an existing inhibitory paradigm and developed a non-parametric framework to measure the trial-by-trial variability of SSRT. A series of simulations verified that the non-parametric approach is on par with a parametric approach and yields accurate estimates of the entire SSRT distribution from as few as ~750 trials. Our results show that in identical settings, the distribution of SSRT is very similar to the distribution of GoRT albeit somewhat shorter, wider and significantly less right-skewed. The ability to measure the precise shapes of SSRT distributions opens new avenues for research into the functional properties of the hyper-direct pathway that is believed to mediate inhibitory control. PMID:26236226

  17. Assessing the Inactivation of Mycobacterium avium subsp. paratuberculosis during Composting of Livestock Carcasses

    PubMed Central

    Tkachuk, Victoria L.; Krause, Denis O.; McAllister, Tim A.; Buckley, Katherine E.; Reuter, Tim; Hendrick, Steve

    2013-01-01

    Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle

  18. The fibroblast growth factor-2 arrests Mycobacterium avium sp. paratuberculosis growth and immunomodulates host response in macrophages.

    PubMed

    Wang, Jianjun; Wang, Zeyou; Yao, Yongliang; Wu, Jianhong; Tang, Xin; Gu, Tao; Li, Guangxin

    2015-07-01

    Mycobacterium tuberculosisis (M. tb) epidemic is one of the most severe health problem worldwide, while mechanisms underlying its pathogenesis and host immune responses remain unclear. Mycobacterium avium (M. avium), a mycobacterial species related to M. tb, shares similarities with M. tb in many ways. In this study, using M. avium infection of macrophages as a model, we systematically studied the effect of fibroblast growth factor-2 (FGF-2) on M. avium infection of macrophages. Our results showed that M. avium infection could increase FGF-2 expression on both mRNA and protein levels. M. avium infection elevated TNF-α and IFN-γ production while the addition of FGF-2 could further increase TNF-α but not IFN-γ level. M. avium infection could increase the expression of oxygen/nitrogen metabolism proteins iNOS and SOD-1, and FGF-2 had additive effect on the expression of these two proteins. M. avium infection had inhibitive effect on actin expression while FGF-2 could partly counteract such inhibition. Moreover, FGF-2 could inhibit M. avium proliferation in macrophages. Our results together indicate that macrophage-secreted FGF-2 upon M. avium infection could suppress M. avium proliferation through various ways including cytokine production, enhancement of phagocytosis as well as oxygen/nitrogen metabolism.

  19. Pathogenicity of Mycobacterium avium for human monocytes: absence of macrophage-activating factor activity of gamma interferon.

    PubMed Central

    Toba, H; Crawford, J T; Ellner, J J

    1989-01-01

    Mycobacterium avium is a frequent opportunistic pathogen in the acquired immunodeficiency syndrome (AIDS). We compared 12 strains of M. avium in an in vitro model of pathogenicity. Peripheral blood-derived monocytes from healthy individuals were infected with M. avium in vitro. Bacterial uptake and intracellular replication were assessed by microscopic count of acid-fast bacilli and CFU of bacteria, respectively, in lysed monocytes. The CFU assay showed that among five AIDS-associated strains, only one replicated in monocytes. Two of seven non-AIDS-associated strains replicated intracellularly. In addition, we examined the effect of gamma interferon (IFN-gamma) on M. avium infection. IFN-gamma treatment of monocytes decreased phagocytosis and had no effect on the intracellular replication of M. avium. Thus, most strains of M. avium do not multiply within monocytes from healthy individuals and IFN-gamma does not have macrophage-activating factor activity for M. avium infection of human monocytes. PMID:2491838

  20. Straddling a paradigm shift

    SciTech Connect

    Landgren, D.

    1995-05-01

    Paul Meagher made a big mistake when he asked me about my speech. I asked him what I should talk about. He reiterated the title of the conference {open_quotes}Forecasting and DSM: Organizing for Success,{close_quotes} and said that whatever issues I wanted to cover were fine with him. As a result I will cover those areas I`ve been thinking about recently. It is hard for me to extract either Forecasting or Demand-Side Management out from the broader issues unwinding in the industry today. I`ve been around long enough to be involved in two major shifts in the industry. I call these paradigm shifts because as a planner I tend to build models in my mind to represent business or regulatory structure. Since a paradigm is defined as a clear model of something, I tend to talk about structural shifts in the industry as paradigm shifts. The first paradigm shift was brought about by the rapid escalation of energy prices in the 1970s. The second paradigm shift, brought about in part because of the first and because of growing concerns about the environment, ushered in the era of utility conservation and load management programs (components of a broader DSM concept - unfortunately today many people limit DSM to only these two pieces). The third paradigm shift is just starting, driven by partial deregulation and the subsequent increase in competition. My talk today will focus on issues related to the second paradigm, particularly in terms of utility planners getting more organized to deal with the synergies in the fields of forecasting, demand-side planning, and evaluation. I will also reflect on two new issues within the existing paradigm that influence these functional areas, namely beneficial electrification and integration of DSM into T&D planning. Finally I will talk about what I see coming as we go through another paradigm shift, particularly as it impacts forecasting and DSM.

  1. Paradigms for machine learning

    NASA Technical Reports Server (NTRS)

    Schlimmer, Jeffrey C.; Langley, Pat

    1991-01-01

    Five paradigms are described for machine learning: connectionist (neural network) methods, genetic algorithms and classifier systems, empirical methods for inducing rules and decision trees, analytic learning methods, and case-based approaches. Some dimensions are considered along with these paradigms vary in their approach to learning, and the basic methods are reviewed that are used within each framework, together with open research issues. It is argued that the similarities among the paradigms are more important than their differences, and that future work should attempt to bridge the existing boundaries. Finally, some recent developments in the field of machine learning are discussed, and their impact on both research and applications is examined.

  2. Communication Policy at the Chalk Face in Scotland and Jamaica: Complexity as a New Paradigm for Understanding Language Policy Interpretation and Implementation.

    ERIC Educational Resources Information Center

    Cross, Beth

    2003-01-01

    Examples from upper primary classrooms in Scotland and Jamaica demonstrate the subtle ways in which teachers support or restrict the classroom use of community languages (Scots and Patwa) through their broad or narrow implementation of language policy. The metaphor of fractals, derived from complexity theory, can form a sensitive and appropriate…

  3. The fictionalist paradigm.

    PubMed

    Paley, John

    2011-01-01

    The fictionalist paradigm is introduced, and differentiated from other paradigms, using the Lincoln & Guba template. Following an initial overview, the axioms of fictionalism are delineated by reference to standard metaphysical categories: the nature of reality, the relationship between knower and known, the possibility of generalization, the possibility of causal linkages, and the role of values in inquiry. Although a paradigm's 'basic beliefs' are arbitrary and can be assumed for any reason, in this paper the fictionalist axioms are supported with philosophical considerations, and the key differences between fictionalism, positivism, and constructivism are briefly explained. Paradigm characteristics are then derived, focusing particularly on the methodological consequences. Towards the end of the paper, various objections and misunderstandings are discussed.

  4. Modulation of the effector function of human monocytes for Mycobacterium avium by human immunodeficiency virus-1 envelope glycoprotein gp120.

    PubMed Central

    Shiratsuchi, H; Johnson, J L; Toossi, Z; Ellner, J J

    1994-01-01

    Disseminated Mycobacterium avium infection in AIDS is associated with high tissue burdens (10(9)-10(10) mycobacteria/g tissue) of organism. The basis for the extraordinary susceptibility of AIDS to M. avium infection is unclear. HIV or its constituents may alter mononuclear phagocyte functions resulting in enhanced intracellular M. avium growth. The effects of an envelope glycoprotein (gp120), a transmembrane protein (p121), and core proteins of HIV-1 on M. avium infection of human monocytes were examined. Preculturing monocytes with gp120 inhibited M. avium phagocytosis and consistently enhanced intracellular growth of six M. avium strains. Pretreatment with p121, gag5, or p24 did not inhibit phagocytosis nor enhance intracellular growth of M. avium. Incubation of gp120 with soluble CD4 before addition to monocyte cultures or pretreatment of monocytes with OKT4A abrogated gp120 effects on M. avium phagocytosis and intracellular growth. gp120 also augmented cytokine production by infected monocytes. These results suggest that gp120, but not p121 or core proteins, modulate monocyte phagocytosis and enhance intracellular growth of M. avium at least in part through monocyte CD4 receptors. Direct effects of HIV-1 products may, therefore, contribute to the diathesis of AIDS to develop disseminated M. avium infection and to the extensive replication of the organisms within tissue macrophages. Images PMID:8113420

  5. Results of volume-staged fractionated Gamma Knife radiosurgery for large complex arteriovenous malformations: obliteration rates and clinical outcomes of an evolving treatment paradigm.

    PubMed

    Franzin, Alberto; Panni, Pietro; Spatola, Giorgio; Vecchio, Antonella Del; Gallotti, Alberto L; Gigliotti, Carmen R; Cavalli, Andrea; Donofrio, Carmine A; Mortini, Pietro

    2016-12-01

    OBJECTIVE There are few reported series regarding volume-staged Gamma Knife radiosurgery (GKRS) for the treatment of large, complex, cerebral arteriovenous malformations (AVMs). The object of this study was to report the results of using volume-staged Gamma Knife radiosurgery for patients affected by large and complex AVMs. METHODS Data from 20 patients with large AVMs were prospectively included in the authors' AVM database between 2004 and 2012. A staging strategy was used when treating lesion volumes larger than 10 cm(3). Hemorrhage and seizures were the presenting clinical feature for 6 (30%) and 8 (40%) patients, respectively. The median AVM volume was 15.9 cm(3) (range 10.1-34.3 cm(3)). The mean interval between stages (± standard deviation) was 15 months (± 9 months). The median margin dose for each stage was 20 Gy (range 18-25 Gy). RESULTS Obliteration was confirmed in 8 (42%) patients after a mean follow-up of 45 months (range 19-87 months). A significant reduction (> 75%) of the original nidal volume was achieved in 4 (20%) patients. Engel Class I-II seizure status was reported by 75% of patients presenting with seizures (50% Engel Class I and 25% Engel Class II) after radiosurgery. After radiosurgery, 71.5% (5/7) of patients who had presented with a worsening neurological deficit reported a complete resolution or amelioration. None of the patients who presented acutely because of hemorrhage experienced a new bleeding episode during follow-up. One (5%) patient developed radionecrosis that caused sensorimotor hemisyndrome. Two (10%) patients sustained a bleeding episode after GKRS, although only 1 (5%) was symptomatic. High nidal flow rate and a time interval between stages of less than 11.7 months were factors significantly associated with AVM obliteration (p = 0.021 and p = 0.041, respectively). Patient age younger than 44 years was significantly associated with a greater than 75% reduction in AVM volume but not with AVM obliteration (p = 0

  6. No holes barred: Invasion of the intestinal mucosa by Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The infection biology of Mycobacterium avium subspecies paratuberculosis (MAP) has recently crystalized with added details surrounding intestinal invasion. The involvement of pathogen-derived effector proteins such as the major membrane protein, oxidoreductase and fibronectin attachment proteins hav...

  7. Composition and potency characterization of Mycobacterium avium subsp. paratuberculosis purified protein derivatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) purified protein derivatives (PPDs) are immunologic reagents prepared from cultured filtrates of the type strain ATCC 19698. Traditional production consists of floating culture incubation at 37oC, organism inactivation by autoclaving, coarse filtrat...

  8. Epidemiology and Ecology of Opportunistic Premise Plumbing Pathogens: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa

    EPA Science Inventory

    BACKGROUND: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are opportunistic premise plumbing pathogens (OPPPs) that persist and grow in household plumbing, habitats they share with humans. Infections caused by these OPPPs involve individuals with preexis...

  9. Immunogenicity of Proteome-determined Mycobacterium avium subsp. paratuberculosis-specific Proteins in Sheep with Paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subspecies paratuberculosis causes paratuberculosis, a chronic granulomatous enteritis. Detecting animals with paratuberculosis infections is difficult because the currently available tools have low sensitivity and lack specificity being prone to spurious positive test results ca...

  10. Involvement of matrix metalloproteinases in human immunodeficiency virus type 1-induced replication by clinical Mycobacterium avium isolates.

    PubMed

    Dezzutti, C S; Swords, W E; Guenthner, P C; Sasso, D R; Wahl, L M; Drummond, A H; Newman, G W; King, C H; Quinn, F D; Lal, R B

    1999-10-01

    The role of Mycobacterium avium isolates in modulating human immunodeficiency virus type 1 (HIV-1) replication was examined by use of an in vitro, resting T cell system. Two human clinical isolates (serotypes 1 and 4) but not an environmental M. avium isolate (serotype 2) enhanced HIV-1 replication. The M. avium-induced HIV-1 replication was not associated with cell activation or differential cytokine production or utilization. Addition of matrix metalloproteinase (MMP) inhibitors and their in vivo regulators, tissue inhibitors of metalloproteinases-1 and -2, abrogated M. avium-induced HIV-1 replication 80%-95%. The MMP inhibitors did not have any effect on the HIV-1 protease activity, suggesting that they may affect cellular processes. Furthermore, MMP-9 protein was differentially expressed after infection with clinical M. avium isolates and paralleled HIV-1 p24 production. Collectively, these data suggest that M. avium-induced HIV-1 replication is mediated, in part, through the induction of MMP-9.

  11. Detection of a novel catalase in extracts of Mycobacterium avium and Mycobacterium intracellulare.

    PubMed Central

    Wayne, L G; Diaz, G A

    1988-01-01

    A novel class of catalase, which differs from the previously described M- and T-catalases of mycobacteria, was detected in strains of Mycobacterium avium and M. intracellulare. Designated A-catalase, this enzyme resisted inactivation at 68 degrees C, was inactivated by 3-amino-1,2,4-triazole (aminotriazole), and exhibited no peroxidase activity. All of these properties distinguished the enzyme from T-catalase. The A-catalase exhibited a Km of 70 mM H2O2, which is between the upper and lower extremes of the ranges reported for T- and M-catalases, respectively. The A-catalase appeared to be more hydrophobic than M-catalase and did not react with antiserum to a representative sample of this class. The banding patterns of T- and M-catalases seen by polyacrylamide gel electrophoresis (PAGE) were essentially unaffected by the incorporation of sodium dodecyl sulfate (SDS) into the PAGE system, whereas the single band of A-catalase seen by PAGE without SDS resolved into as many as five bands in the presence of SDS; these bands were all of slower mobility than the original band. The banding pattern seen with SDS appeared to be related more to counterion charge effects than to molecular size increases that could be attributed to SDS complexed to the protein. It remains to be determined whether the multiple A-catalase bands reflect different proteins or different SDS micellar complexes of a single protein. Images PMID:3346077

  12. Effect of lipoarabinomannan from Mycobacterium avium subsp avium in Freund's incomplete adjuvant on the immune response of cattle

    PubMed Central

    Colavecchia, S.B.; Jolly, A.; Fernández, B.; Fontanals, A.M.; Fernández, E.; Mundo, S.L.

    2012-01-01

    The aim of the present study was to determine whether lipoarabinomannan (LAM), in combination with Freund's incomplete adjuvant (FIA), was able to improve cell-mediated and antibody-mediated immune responses against ovalbumin (OVA) in cattle. Twenty-three calves were assigned to four treatment groups, which were subcutaneously immunized with either OVA plus FIA, OVA plus FIA and LAM from Mycobacterium avium subsp avium, FIA plus LAM, or FIA alone. Lymphoproliferation, IFN-γ production and cell subpopulations on peripheral blood mononuclear cells before and 15 days after treatment were evaluated. Delayed hypersensitivity was evaluated on day 57. Specific humoral immune response was measured by ELISA. Inoculation with LAM induced higher levels of lymphoproliferation and IFN-γ production in response to ConA and OVA (P < 0.05). Specific antibody titers were similar in both OVA-immunized groups. Interestingly, our results showed that the use of LAM in vaccine preparations improved specific cell immune response evaluated by lymphoproliferation and IFN-γ production by at least 50 and 25%, respectively, in cattle without interfering with tuberculosis and paratuberculosis diagnosis. PMID:22286534

  13. Occurrence of Mycobacterium avium subsp. paratuberculosis in untreated water in Northern Ireland.

    PubMed

    Whan, Lynne; Ball, Hywel J; Grant, Irene R; Rowe, Michael T

    2005-11-01

    Mycobacterium avium subsp. paratuberculosis is the known cause of Johne's disease of both domestic and wild ruminants and has been implicated as a possible cause of Crohn's disease in humans. The organism is shed in the feces of infected animals and can survive for protracted periods in the environment and hence could be present in catchment areas receiving agricultural runoff. A limited survey was undertaken in Northern Ireland to test for M. avium subsp. paratuberculosis in untreated water entering nine water treatment works (WTWs) over a 1-year period. Three detection methods were employed, viz., immunomagnetic separation-PCR and culture on Herrold's egg yolk medium (HEYM) and BACTEC 12B medium, the latter both supplemented with mycobactins. Of the 192 untreated water samples tested, 15 (8%) tested M. avium subsp. paratuberculosis positive by one or more of the three detection methods. M. avium subsp. paratuberculosis was successfully isolated from eight untreated water samples, three by BACTEC culture and five by culture on HEYM. Although the highest incidence of M. avium subsp. paratuberculosis was found in spring, overall, there was no statistically significant difference between the seasons. No significant correlation was found between numbers of coliforms or fecal coliforms and the presence of M. avium subsp. paratuberculosis. In general, a higher incidence of M. avium subsp. paratuberculosis was found in untreated water entering those WTWs that had a high mean water pH value over the sampling period. This work indicates the need to determine the efficacy of water treatment processes to either kill or remove M. avium subsp. paratuberculosis from untreated water and the possible risks posed by contact with recreational water sources.

  14. Infection by Mycobacterium avium intracellulare in AIDS: endoscopic duodenal appearance mimicking Whipple's disease.

    PubMed

    Vázquez-Iglesias, J L; Yañez, J; Durana, J; Arnal, F

    1988-09-01

    We report the case of a 24-year-old woman who presented with diarrhea, weight loss and abdominal lymph node enlargement. A diagnosis of infection by Mycobacterium avium intracellulare with a clinical picture similar to Whipple's disease was established. The endoscopic study of the duodenum revealed multiple yellow nodules that became confluent in the second portion, entirely replacing the normal mucosa. These endoscopic findings have not been described previously in intestinal infection by Mycobacterium avium intracellulare.

  15. Pulmonary collectins play distinct roles in host defense against Mycobacterium avium.

    PubMed

    Ariki, Shigeru; Kojima, Takashi; Gasa, Shinsei; Saito, Atsushi; Nishitani, Chiaki; Takahashi, Motoko; Shimizu, Takeyuki; Kurimura, Yuichiro; Sawada, Norimasa; Fujii, Nobuhiro; Kuroki, Yoshio

    2011-09-01

    Pulmonary collectins, surfactant protein A (SP-A) and surfactant protein D (SP-D), play important roles in the innate immunity of the lung. Mycobacterium avium is one of the well-known opportunistic pathogens that can replicate within macrophages. We examined the effects of pulmonary collectins in host defense against M. avium infection achieved via direct interaction between bacteria and collectins. Although both pulmonary collectins bound to M. avium in a Ca(2+)-dependent manner, these collectins revealed distinct ligand-binding specificity and biological activities. SP-A and SP-D bound to a methoxy group containing lipid and lipoarabinomannan, respectively. Binding of SP-D but not SP-A resulted in agglutination of M. avium. A chimeric protein with the carbohydrate recognition domain of SP-D, which chimera revealed a bouquet-like arrangement similar to SP-A, also agglutinated M. avium. The ligand specificity of the carbohydrate recognition domain of SP-D seems to be necessary for agglutination activity. The binding of SP-A strongly inhibited the growth of M. avium in culture media. Although pulmonary collectins did not increase membrane permeability of M. avium, they attenuated the metabolic rate of the bacteria. Observations under a scanning electron microscope revealed that SP-A almost completely covers bacterial surfaces, whereas SP-D binds to certain areas like scattered dots. These observations suggest that a distinct binding pattern of collectins correlates with the difference of their biological activities. Furthermore, the number of bacteria phagocytosed by macrophages was significantly increased in the presence of SP-D. These data indicate that pulmonary collectins play critical roles in host defense against M. avium.

  16. Changing the Paradigm of Air Pollution Monitoring

    EPA Science Inventory

    Historically, approaches for monitoring air pollution generally use expensive, complex, stationary equipment,1,2 which limits who collects data, why data are collected, and how data are accessed. This paradigm is changing with the materialization of lower-cost, easy-to...

  17. Maximizing Capture Efficiency and Specificity of Magnetic Separation for Mycobacterium avium subsp. paratuberculosis Cells ▿

    PubMed Central

    Foddai, Antonio; Elliott, Christopher T.; Grant, Irene R.

    2010-01-01

    In order to introduce specificity for Mycobacterium avium subsp. paratuberculosis prior to a phage amplification assay, various magnetic-separation approaches, involving either antibodies or peptides, were evaluated in terms of the efficiency of capture (expressed as a percentage) of M. avium subsp. paratuberculosis cells and the percentage of nonspecific binding by other Mycobacterium spp. A 50:50 mixture of MyOne Tosylactivated Dynabeads coated with the chemically synthesized M. avium subsp. paratuberculosis-specific peptides biotinylated aMp3 and biotinylated aMptD (i.e., peptide-mediated magnetic separation [PMS]) proved to be the best magnetic-separation approach for achieving 85 to 100% capture of M. avium subsp. paratuberculosis and minimal (<1%) nonspecific recovery of other Mycobacterium spp. (particularly if beads were blocked with 1% skim milk before use) from broth samples containing 103 to 104 CFU/ml. When PMS was coupled with a recently optimized phage amplification assay and used to detect M. avium subsp. paratuberculosis in 50-ml volumes of spiked milk, the mean 50% limit of detection (LOD50) was 14.4 PFU/50 ml of milk (equivalent to 0.3 PFU/ml). This PMS-phage assay represents a novel, rapid method for the detection and enumeration of viable M. avium subsp. paratuberculosis organisms in milk, and potentially other sample matrices, with results available within 48 h. PMID:20851966

  18. Maximum growth rate of Mycobacterium avium in continuous culture or chronically infected BALB/c mice.

    PubMed

    McCarthy, C M; Taylor, M A; Dennis, M W

    1987-01-01

    Mycobacterium avium is a human pathogen which may cause either chronic or disseminated disease and the organism exhibits a slow rate of growth. This study provides information on the growth rate of the organism in chronically infected mice and its maximal growth rate in vitro. M. avium was grown in continuous culture, limited for nitrogen with 0.5 mM ammonium chloride and dilution rates that ranged from 0.054 to 0.153 h-1. The steady-state concentration of ammonia nitrogen and M. avium cells for each dilution rate were determined. The bacterial saturation constant for growth-limiting ammonia was 0.29 mM (4 micrograms nitrogen/ml) and, from this, the maximal growth rate for M. avium was estimated to be 0.206 h-1 or a doubling time of 3.4 h. BALB/c mice were infected intravenously with 3 x 10(6) colony-forming units and a chronic infection resulted, typical of virulent M. avium strains. During a period of 3 months, the number of mycobacteria remained constant in the lungs, but increased 30-fold and 8,900-fold, respectively, in the spleen and mesenteric lymph nodes. The latter increase appeared to be due to proliferation in situ. The generation time of M. avium in the mesenteric lymph nodes was estimated to be 7 days.

  19. Biologically distinct subtypes of Mycobacterium avium differ in possession of insertion sequence IS901.

    PubMed

    Kunze, Z M; Portaels, F; McFadden, J J

    1992-09-01

    Mycobacterium avium causes disease, principally tuberculosis in immunocompromised individuals. It is the most frequent cause of disseminated infections in AIDS patients in the West. The pathogen is also associated with disease in animals, chiefly birds and livestock, and may be isolated from environmental samples such as soil and water. Analysis of strains of M. avium isolated from clinical, veterinary, and environmental sources for the presence of the mycobacterial insertion sequences IS900 and IS901 demonstrates the specific association of IS901 to animal pathogenic M. avium strains. In contrast, most clinical M. avium strains and all AIDS-derived strains examined so far lacked IS901. Significant differences in the plasmid contents and serotypes of strains with and without IS901 were also found. We therefore suggest that the presence of IS901 divides M. avium into two clearly distinct subtypes with differing host range, virulence, plasmid possession, and serotyping antigens. By using DNA sequence data from IS901 and M. avium DNA, a set of polymerase chain reactions were developed for the specific detection and differentiation of these subtypes.

  20. Comparative genome analyses of Mycobacterium avium reveal genomic features of its subspecies and strains that cause progression of pulmonary disease

    PubMed Central

    Uchiya, Kei-ichi; Tomida, Shuta; Nakagawa, Taku; Asahi, Shoki; Nikai, Toshiaki; Ogawa, Kenji

    2017-01-01

    Pulmonary disease caused by nontuberculous mycobacteria (NTM) is increasing worldwide. Mycobacterium avium is the most clinically significant NTM species in humans and animals, and comprises four subspecies: M. avium subsp. avium (MAA), M. avium subsp. silvaticum (MAS), M. avium subsp. paratuberculosis (MAP), and M. avium subsp. hominissuis (MAH). To improve our understanding of the genetic landscape and diversity of M. avium and its role in disease, we performed a comparative genome analysis of 79 M. avium strains. Our analysis demonstrated that MAH is an open pan-genome species. Phylogenetic analysis based on single nucleotide variants showed that MAH had the highest degree of sequence variability among the subspecies, and MAH strains isolated in Japan and those isolated abroad possessed distinct phylogenetic features. Furthermore, MAP strains, MAS and MAA strains isolated from birds, and many MAH strains that cause the progression of pulmonary disease were grouped in each specific cluster. Comparative genome analysis revealed the presence of genetic elements specific to each lineage, which are thought to be acquired via horizontal gene transfer during the evolutionary process, and identified potential genetic determinants accounting for the pathogenic and host range characteristics of M. avium. PMID:28045086

  1. Imidazo[1,2-a]Pyridine-3-Carboxamides Are Active Antimicrobial Agents against Mycobacterium avium Infection In Vivo

    PubMed Central

    Moraski, Garrett C.; Cheng, Yong; Cho, Sanghyun; Cramer, Jeffrey W.; Godfrey, Alexander; Masquelin, Thierry; Franzblau, Scott G.; Miller, Marvin J.

    2016-01-01

    A panel of six imidazo[1,2-a]pyridine-3-carboxamides (IAPs) were shown to have low-micromolar activity against Mycobacterium avium strains. Compound ND-10885 (compound 2) showed significant activity in the lung, spleen, and liver in a mouse M. avium infection model. A combined regimen consisting of ND-10885 (compound 2) and rifampin was additive in its anti-M. avium activity in the lung. Our data indicate that IAPs represent a new class of antibiotics that are active against M. avium and could potentially serve as an effective addition to a combined treatment regimen. PMID:27216051

  2. Mycobacterium avium subspecies paratuberculosis, Crohn's disease and the Doomsday scenario

    PubMed Central

    Hermon-Taylor, John

    2009-01-01

    Johne's disease is chronic inflammation of the intestine caused by Mycobacterium avium subspecies paratuberculosis. Infection and disease are mainly in domestic livestock but can affect many species including primates. Johne's is a new disease which emerged at the turn of the 19th and 20th centuries and principally involved Europe and North America. It has since spread to former low incidence regions to become a global problem. Crohn's disease is a chronic inflammation of the intestine in humans which emerged in Europe and North America mid 20th century and increased to become a major healthcare problem. It has now spread to former low incidence regions. Infected animals shed Mycobacterium avium subspecies paratuberculosis in milk and into the environment. Human populations are widely exposed. Outcomes maybe influenced by microbial phenotype. Exposure to extracellular forms of these pathogens may confer some natural protection; exposure to intracellular forms which have passaged through milk macrophages or environmental protists may pose a greater threat to humans particularly individuals with an inherited or acquired susceptibility. Hot spots of human disease such as in Winnipeg which sits on rock at the junction of two rivers may result from local exposure to high levels of waterborne pathogens brought down from farmland. When appropriate methods are used most people with Crohn's disease are found to be infected. There are no data which demonstrate that these pathogens are harmless to humans. An overwhelming balance of probability and Public health risk favours the conclusion that Mycobacterium avium subspecies paratuberculosis is also pathogenic for people. A two tier co-operative pathogenic mechanism is proposed in Crohn's disease. Intracellular infection with the primary pathogen widely distributed throughout the gut causes an immune dysregulation and a specific chronic enteric neuropathy with loss of mucosal integrity. Segments of gross inflammatory disease

  3. The Learning Paradigm College.

    ERIC Educational Resources Information Center

    Tagg, John

    The author of this book argues that innovations do not transform colleges because higher education faces a problem of scale. The book identifies two paradigms: "organizational," which is the overall theory-in-use of an organization; and "instructional," which incorporates the mission of higher education institutions to provide instruction in the…

  4. Deconstructing Research: Paradigms Lost

    ERIC Educational Resources Information Center

    Trifonas, Peter Pericles

    2009-01-01

    In recent decades, proponents of naturalistic and/or critical modes of inquiry advocating the use of ethnographic techniques for the narrative-based study of phenomena within pedagogical contexts have challenged the central methodological paradigm of educational research: that is, the tendency among its practitioners to adhere to quantitative…

  5. Paradigms of School Change

    ERIC Educational Resources Information Center

    Wrigley, Terry

    2011-01-01

    This short paper points to some paradigm issues in the field of school development (leadership, effectiveness, improvement) and their relationship to social justice. It contextualises the dominant School Effectiveness and School Improvement models within neo-liberal marketisation, paying attention to their transformation through a "marriage of…

  6. Alternative Evaluation Research Paradigm.

    ERIC Educational Resources Information Center

    Patton, Michael Quinn

    This monograph is one of a continuing series initiated to provide materials for teachers, parents, school administrators, and governmental decision-makers that might encourage reexamination of a range of evaluation issues and perspectives about schools and schooling. This monograph is a description and analysis of two contrasting paradigms: one…

  7. Primary transcriptomes of Mycobacterium avium subsp. paratuberculosis reveal proprietary pathways in tissue and macrophages

    PubMed Central

    2010-01-01

    Background Mycobacterium avium subsp. paratuberculosis (MAP) persistently infects intestines and mesenteric lymph nodes leading to a prolonged subclinical disease. The MAP genome sequence was published in 2005, yet its transcriptional organization in natural infection is unknown. While prior research analyzed regulated gene sets utilizing defined, in vitro stress related or advanced surgical methods with various animal species, we investigated the intracellular lifestyle of MAP in the intestines and lymph nodes to understand the MAP pathways that function to govern this persistence. Results Our transcriptional analysis shows that 21%, 8% and 3% of the entire MAP genome was represented either inside tissues, macrophages or both, respectively. Transcripts belonging to latency and cell envelope biogenesis were upregulated in the intestinal tissues whereas those belonging to intracellular trafficking and secretion were upregulated inside the macrophages. Transcriptomes of natural infection and in vitro macrophage infection shared genes involved in transcription and inorganic ion transport and metabolism. MAP specific genes within large sequence polymorphisms of ancestral M. avium complex were downregulated exclusively in natural infection. Conclusions We have unveiled common and unique MAP pathways associated with persistence, cell wall biogenesis and virulence in naturally infected cow intestines, lymph nodes and in vitro infected macrophages. This dichotomy also suggests that in vitro macrophage models may be insufficient in providing accurate information on the events that transpire during natural infection. This is the first report to examine the primary transcriptome of MAP at the local infection site (i.e. intestinal tissue). Regulatory pathways that govern the lifecycle of MAP appear to be specified by tissue and cell type. While tissues show a "shut-down" of major MAP metabolic genes, infected macrophages upregulate several MAP specific genes along with a

  8. Emphysematous pyometra secondary to Enterococcus avium infection in a dog.

    PubMed

    Chang, An-Chi; Cheng, Ching-Chang; Wang, Hsien-Chi; Lee, Wei-Ming; Shyu, Ching-Lin; Lin, Cheng-Chung; Chen, Kuan-Sheng

    2016-06-16

    A 5-year-old female intact Mastiff dog was presented with a history of vaginal discharge for 1 day. Physical examination revealed a sanguineo-purulent vaginal discharge and systemic inflammatory response syndrome. Abdominal radiographs showed several dilated and gas- filled tubular loops. The differential diagnoses included emphysematous pyometra or small intestinal mechanical ileus. Surgical exploration of the abdomen demonstrated a severely dilated and gas-filled uterus, and emphysematous pyometra was confirmed. The patient's clinical signs resolved after ovariohysterectomy. Histopathology revealed mild endometrial cystic hyperplasia with infiltration of inflammatory cells in the superficial endometrial epithelia. Enterococcus avium, an α-hemolytic gram-positive coccus, was isolated from the uterus. This paper highlights the radiographic features of emphysematous pyometra and a pathogen that has never been reported to be associated with canine pyometra previously.

  9. Molecular Epidemiology of Mycobacterium avium subsp. paratuberculosis on Dairy Farms.

    PubMed

    Li, Lingling; Katani, Robab; Schilling, Megan; Kapur, Vivek

    2016-01-01

    Mycobacterium avium subspecies paratuberculosis (MAP) is the etiological agent of severe chronic intestinal inflammatory disease in ruminants, termed Johne's disease, and can infect many other animal species, including humans. MAP has a long incubation period prior to manifestation of clinical signs including diarrhea, weight loss, and loss of production. MAP has a high prevalence in dairy herds and results in considerable adverse impacts on animal health and productivity throughout the world. Recent investigations have leveraged the characterization of the MAP genome for the development of powerful new molecular techniques for MAP strain differentiation. These approaches are providing key insights into the epidemiology and transmission of MAP on and between dairy herds. We summarize the state of the art for MAP diagnostics and strain differentiation and our current knowledge of mechanisms of within- and between-herd transmission of MAP, along with future needs for the development of rational MAP infection control programs.

  10. Influence of cultivar and processing on cherry (Prunus avium) allergenicity.

    PubMed

    Primavesi, L; Brenna, O V; Pompei, C; Pravettoni, V; Farioli, L; Pastorello, E A

    2006-12-27

    Oral allergy syndrome is an immediate food allergic event that affects lips, mouth, and pharynx, is often triggered by fruits and vegetables, and may be associated with pollinosis. Here, we report on the allergenic pattern of different varieties of cherry (Prunus avium) and results obtained by applying several technological processes to the selected varieties. Whole cherries were submitted to chemical peeling, thermal treatment, and syruping processes, and the relative protein extracts were analyzed by in vitro (sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting analysis) and in vivo tests (skin prick test). Electrophoretic analyses demonstrated that there was no marked difference among cherry cultivars. Chemical peeling successfully removed Pru av 3, a lipid transfer protein (LTP) responsible for oral allergy syndrome in patients without pollinosis, leading to the industrial production of cherry hypoallergenic derivatives. Furthermore, the syruping process removed almost all allergenic proteins to whom patients with pollinosis are responsive. In vivo tests confirmed electrophoretic results.

  11. Phosphoenolpyruvate carboxykinase in cherry (Prunus avium L.) fruit during development.

    PubMed

    Walker, Robert P; Battistelli, Alberto; Moscatello, Stefano; Chen, Zhi-Hui; Leegood, Richard C; Famiani, Franco

    2011-11-01

    In this study the abundance and location of phosphoenolpyruvate carboxykinase (PEPCK) was determined in the flesh and skin of the sweet cherry (Prunus avium L.) cultivar Durone Nero II during development. PEPCK was not present in young fruit but appeared in both tissues as the fruit increased in size. In these there was no net dissimilation of malic acid, which accounts for the bulk of their organic acid contents when PEPCK was present. To assist in understanding the function of PEPCK, the abundance of a number of other enzymes was determined. These enzymes were aspartate aminotransferase (AspAT), glutamine synthetase (GS), phosphoenolpyruvate carboxylase (PEPC), pyruvate, orthophosphate dikinase (PPDK), and ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco). A potential role for PEPCK in the regulation of pH and the utilization of malate in gluconeogenesis in the flesh and skin of cherries is presented.

  12. Bayesian kriging of seroprevalence to Mycobacterium avium subspecies paratuberculosis and Neospora caninum in Alberta beef and dairy cattle.

    PubMed

    Thompson, James A; Scott, H Morgan

    2007-12-01

    Identifying spatial patterns of risk is important in the study of diseases with ecologic causes. Furthermore, relatively complex hierarchical modeling is required to determine how factors that are organized across levels interact, such as how an ecologic cause interacts with farm management and with animal characteristics. The objective of this study was to map the risk for Mycobacterium avium subspecies paratuberculosis (MAP - the causative agent of Johne's disease) and Neospora caninum (NC - the cause of neosporosis) infections in Alberta beef and dairy cattle. This objective utilized Bayesian generalized linear kriging to partition herd effects into a portion attributable to location and a portion that was independent of location. Seropositivity to NC in beef cattle showed strong support for spatial covariance, suggesting that ecologic causes were important for beef cattle but not dairy cattle. There was little evidence of spatial covariance for MAP seropositivity in either beef or dairy cattle.

  13. Bayesian kriging of seroprevalence to Mycobacterium avium subspecies paratuberculosis and Neospora caninum in Alberta beef and dairy cattle

    PubMed Central

    Thompson, James A.; Scott, H. Morgan

    2007-01-01

    Identifying spatial patterns of risk is important in the study of diseases with ecologic causes. Furthermore, relatively complex hierarchical modeling is required to determine how factors that are organized across levels interact, such as how an ecologic cause interacts with farm management and with animal characteristics. The objective of this study was to map the risk for Mycobacterium avium subspecies paratuberculosis (MAP — the causative agent of Johne’s disease) and Neospora caninum (NC — the cause of neosporosis) infections in Alberta beef and dairy cattle. This objective utilized Bayesian generalized linear kriging to partition herd effects into a portion attributable to location and a portion that was independent of location. Seropositivity to NC in beef cattle showed strong support for spatial covariance, suggesting that ecologic causes were important for beef cattle but not dairy cattle. There was little evidence of spatial covariance for MAP seropositivity in either beef or dairy cattle. PMID:18189052

  14. The Nature of Paradigms and Paradigm Shifts in Music Education

    ERIC Educational Resources Information Center

    Panaiotidi, Elvira

    2005-01-01

    In this paper, the author attempts to extend the paradigm approach into the philosophy of music education and to build upon this basis a model for structuring music education discourse. The author begins with an examination of Peter Abbs' account of paradigms and paradigm shifts in arts education. Then she turns to Kuhn's conception and to his…

  15. Mycobacterium avium subsp. paratuberculosis as a trigger of type-1 diabetes: destination Sardinia, or beyond?

    PubMed

    Rani, Pittu Sandhya; Sechi, Leonardo A; Ahmed, Niyaz

    2010-03-29

    Type 1 diabetes mellitus (T1DM) is a multifactorial autoimmune disease in which the insulin producing beta cell population is destroyed by the infiltrated T lymphocytes. Even though the exact cause of T1DM is yet to be ascertained, varying degree of genetic susceptibility and environmental factors have been linked to the disease progress and outcome. Mycobacterium avium subsp. paratuberculosis (MAP) is an obligate zoonotic pathogen that causes chronic infection of intestines in ruminants, the Johne's disease. MAP that can even survive pasteurization and chlorination has also been implicated to cause similar type of enteritis in humans called Crohn's disease. With the increasing recognition of the link between MAP and Crohn's disease, it has been postulated that MAP is an occult antigen which besides Crohn's could as well be thought to trigger T1DM. Epitope homologies between mycobacterial proteins (Hsp 65) and pancreatic glutamic acid decarboxylase (GAD 65) and infant nutrition studies implicate MAP as one of the triggers for T1DM. PCR and ELISA analyses in diabetic patients from Sardinia suggest that MAP acts as a possible trigger for T1DM. Systematic mechanistic insights are needed to prove this link. Unfortunately, no easy animal model(s) or in-vitro systems are available to decipher the complex immunological network that is triggered in MAP infection leading to T1DM.

  16. LAMP technology: Rapid identification of Brucella and Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Trangoni, Marcos D.; Gioffré, Andrea K.; Cerón Cucchi, María E.; Caimi, Karina C.; Ruybal, Paula; Zumárraga, Martín J.; Cravero, Silvio L.

    2015-01-01

    In this study, we developed new sets of primers to detect Brucella spp. and M. avium subsp. paratuberculosis (MAP) through isothermal amplification. We selected a previously well-characterized target gene, bscp31, specific for Brucella spp. and IS900 for MAP. The limits of detection using the loop-mediated isothermal amplification (LAMP) protocols described herein were similar to those of conventional PCR targeting the same sequences. Hydroxynaphtol blue and SYBR GreenTM allowed direct naked-eye detection with identical sensitivity as agarose gel electrophoresis. We included the LAMP-based protocol in a rapid identification scheme of the respective pathogens, and all tested isolates were correctly identified within 2 to 3 h. In addition, both protocols were suitable for specifically identifying the respective pathogens; in the case of Brucella, it also allowed the identification of all the biovars tested. We conclude that LAMP is a suitable rapid molecular typing tool that could help to shorten the time required to identify insidious bacteria in low-complexity laboratories, mainly in developing countries. PMID:26273282

  17. The activity of grepafloxacin in two murine models of Mycobacterium avium infection.

    PubMed

    Cynamon, Michael H; Sklaney, Mary; Yeo, Anthony E T

    2004-06-01

    The activity against Mycobacterium avium complex (MAC) of varying doses of grepafloxacin (GRE; 25 mg/kg, 50 mg/kg, 100 mg/kg, and 200 mg/kg) were compared to clarithromycin (CLA; 100 mg/kg and 200 mg/kg), ethambutol (EMB; 100 mg/kg), and rifabutin (RBT; 10 mg/kg) using an intranasal (IN) infection model compared to an intravenous (IV) infection model. Beige mice (C57BL6/J-Lyst bg J/+) were infected intranasally with about 10(6) organisms and for the IV model about 10(7) organisms. Treatment for both models was started 1 week postinfection and given by gavage 5 days/week for 4 weeks. At the initiation of therapy, an early control group was killed to determine the initial organism load. Three days following the completion of therapy, drug-treated groups of mice and the late control group were killed and the response to therapy measured. The most effective agents were CLA and RBT. GRE and EMB had modest activities in both the IN and the IV models. A matched comparison between IN and IV challenges for each of the agents used revealed greater suppression of MAC in the IN model compared to the IV model.

  18. Mycobacterium avium subsp. paratuberculosis as a trigger of type-1 diabetes: destination Sardinia, or beyond?

    PubMed Central

    2010-01-01

    Type 1 diabetes mellitus (T1DM) is a multifactorial autoimmune disease in which the insulin producing β cell population is destroyed by the infiltrated T lymphocytes. Even though the exact cause of T1DM is yet to be ascertained, varying degree of genetic susceptibility and environmental factors have been linked to the disease progress and outcome. Mycobacterium avium subsp. paratuberculosis (MAP) is an obligate zoonotic pathogen that causes chronic infection of intestines in ruminants, the Johne's disease. MAP that can even survive pasteurization and chlorination has also been implicated to cause similar type of enteritis in humans called Crohn's disease. With the increasing recognition of the link between MAP and Crohn's disease, it has been postulated that MAP is an occult antigen which besides Crohn's could as well be thought to trigger T1DM. Epitope homologies between mycobacterial proteins (Hsp 65) and pancreatic glutamic acid decarboxylase (GAD 65) and infant nutrition studies implicate MAP as one of the triggers for T1DM. PCR and ELISA analyses in diabetic patients from Sardinia suggest that MAP acts as a possible trigger for T1DM. Systematic mechanistic insights are needed to prove this link. Unfortunately, no easy animal model(s) or in-vitro systems are available to decipher the complex immunological network that is triggered in MAP infection leading to T1DM. PMID:20350307

  19. LAMP technology: Rapid identification of Brucella and Mycobacterium avium subsp. paratuberculosis.

    PubMed

    Trangoni, Marcos D; Gioffré, Andrea K; Cerón Cucchi, María E; Caimi, Karina C; Ruybal, Paula; Zumárraga, Martín J; Cravero, Silvio L

    2015-06-01

    In this study, we developed new sets of primers to detect Brucella spp. and M. avium subsp. paratuberculosis (MAP) through isothermal amplification. We selected a previously well-characterized target gene, bscp31, specific for Brucella spp. and IS900 for MAP. The limits of detection using the loop-mediated isothermal amplification (LAMP) protocols described herein were similar to those of conventional PCR targeting the same sequences. Hydroxynaphtol blue and SYBR Green(TM) allowed direct naked-eye detection with identical sensitivity as agarose gel electrophoresis. We included the LAMP-based protocol in a rapid identification scheme of the respective pathogens, and all tested isolates were correctly identified within 2 to 3 h. In addition, both protocols were suitable for specifically identifying the respective pathogens; in the case of Brucella, it also allowed the identification of all the biovars tested. We conclude that LAMP is a suitable rapid molecular typing tool that could help to shorten the time required to identify insidious bacteria in low-complexity laboratories, mainly in developing countries.

  20. A synchronous paradigm for modeling stable reactive systems

    SciTech Connect

    Winter, V.L.

    1998-12-01

    This paper describes a modeling technique for single-agent reactive systems, that is influenced by the modeling paradigm of Parnas as well as by the synchronous paradigms of LUSTRE and ESTEREL. In this paradigm, single-agent reactive systems are modeled in a universe having a discrete clock. This discretization of time greatly reduces the temporal complexity of the model. He believes that the advantage of this reduction in temporal complexity is that the resulting model is in many ways better suited to automated software construction and analysis techniques (e.g., deductive synthesis, transformation, and verification) than models that are based on continuous representations of time.

  1. Survival of Mycobacterium avium in drinking water biofilms as affected by water flow velocity, availability of phosphorus, and temperature.

    PubMed

    Torvinen, Eila; Lehtola, Markku J; Martikainen, Pertti J; Miettinen, Ilkka T

    2007-10-01

    Mycobacterium avium is a potential pathogen occurring in drinking water systems. It is a slowly growing bacterium producing a thick cell wall containing mycolic acids, and it is known to resist chlorine better than many other microbes. Several studies have shown that pathogenic bacteria survive better in biofilms than in water. By using Propella biofilm reactors, we studied how factors generally influencing the growth of biofilms (flow rate, phosphorus concentration, and temperature) influence the survival of M. avium in drinking water biofilms. The growth of biofilms was followed by culture and DAPI (4',6'-diamidino-2-phenylindole) staining, and concentrations of M. avium were determined by culture and fluorescence in situ hybridization methods. The spiked M. avium survived in biofilms for the 4-week study period without a dramatic decline in concentration. The addition of phosphorus (10 microg/liter) increased the number of heterotrophic bacteria in biofilms but decreased the culturability of M. avium. The reason for this result is probably that phosphorus increased competition with other microbes. An increase in flow velocity had no effect on the survival of M. avium, although it increased the growth of biofilms. A higher temperature (20 degrees C versus 7 degrees C) increased both the number of heterotrophic bacteria and the survival of M. avium in biofilms. In conclusion, the results show that in terms of affecting the survival of slowly growing M. avium in biofilms, temperature is a more important factor than the availability of nutrients like phosphorus.

  2. Mycobacterium avium infections of Acanthamoeba strains: host strain variability, grazing-acquired infections, and altered dynamics of inactivation with monochloramine.

    PubMed

    Berry, David; Horn, Matthias; Xi, Chuanwu; Raskin, Lutgarde

    2010-10-01

    Stable Mycobacterium avium infections of several Acanthamoeba strains were characterized by increased infection resistance of recent environmental isolates and reduced infectivity in the presence of other bacteria. Exposure of M. avium in coculture with Acanthamoeba castellanii to monochloramine yielded inactivation kinetics markedly similar to those observed for A. castellanii alone.

  3. The persistence of Mycobacterium avium in a drinking water system, what is the risk to human health?

    EPA Science Inventory

    Drinking water is believed to be a major source of human exposure to nontuberculous mycobacteria (NTM) such as Mycobacterium avium. We monitored the prevalence of M. avium in a drinking water system during the addition of filtration treatment. Our goal was to determine if the pre...

  4. ISOLATION OF THE GENOME SEQUENCE STRAIN MYCOBACTERIUM AVIUM 104 FROM MULTIPLE PATIENTS OVER A 17-YEAR PERIOD

    EPA Science Inventory

    The genome sequence strain 104 of the opportunistic pathogen Mycobacterium avium was isolated form an adult AIDS patient in Southern California in 1983. Isolates of non-paratuberculosis M. avium from 207 other patients in Southern California and elsewhere were examined for genoty...

  5. Identification of Mycobacterium avium genes associated with resistance to host antimicrobial peptides

    PubMed Central

    Motamedi, Nima; Danelishvili, Lia

    2014-01-01

    Antimicrobial peptides are an important component of the innate immune defence. Mycobacterium avium subsp. hominissuis (M. avium) is an organism that establishes contact with the respiratory and gastrointestinal mucosa as a necessary step for infection. M. avium is resistant to high concentrations of polymyxin B, a surrogate for antimicrobial peptides. To determine gene-encoding proteins that are associated with this resistance, we screened a transposon library of M. avium strain 104 for susceptibility to polymyxin B. Ten susceptible mutants were identified and the inactivated genes sequenced. The great majority of the genes were related to cell wall synthesis and permeability. The mutants were then examined for their ability to enter macrophages and to survive macrophage killing. Three clones among the mutants had impaired uptake by macrophages compared with the WT strain, and all ten clones were attenuated in macrophages. The mutants were also shown to be susceptible to cathelicidin (LL-37), in contrast to the WT bacterium. All but one of the mutants were significantly attenuated in mice. In conclusion, this study indicated that the M. avium envelope is the primary defence against host antimicrobial peptides. PMID:24836414

  6. Mycobacterium avium bacilli grow saprozoically in coculture with Acanthamoeba polyphaga and survive within cyst walls.

    PubMed

    Steinert, M; Birkness, K; White, E; Fields, B; Quinn, F

    1998-06-01

    Protozoans are gaining recognition as environmental hosts for a variety of waterborne pathogens. We compared the growth of Mycobacterium avium, a human pathogen associated with domestic water supplies, in coculture with the free-living amoeba Acanthamoeba polyphaga with the growth of M. avium when it was separated from amoebae by a 0.1-micron-pore-size polycarbonate membrane (in a parachamber). Although viable mycobacteria were observed within amoebal vacuoles, there was no significant difference between bacterial growth in coculture and bacterial growth in the parachamber. This suggests that M. avium is able to grow saprozoically on products secreted by the amoebae. In contrast, Legionella pneumophila, a well-studied intracellular parasite of amoebae, multiplied only in coculture. A comparison of amoebae infected with L. pneumophila and amoebae infected with M. avium by electron microscopy demonstrated that there were striking differences in the locations of the bacteria within amoebal cysts. While L. pneumophila resided within the cysts, M. avium was found within the outer walls of the double-walled cysts of A. polyphaga. These locations may provide a reservoir for the bacteria when environmental conditions become unfavorable.

  7. Immunoreactivity of protein tyrosine phosphatase A (PtpA) in sera from sheep infected with Mycobacterium avium subspecies paratuberculosis.

    PubMed

    Gurung, Ratna B; Begg, Douglas J; Purdie, Auriol C; Bach, Horacio; Whittington, Richard J

    2014-07-15

    Evasion of host defense mechanisms and survival inside infected host macrophages are features of pathogenic mycobacteria including Mycobacterium avium subspecies paratuberculosis, the causative agent of Johne's disease in ruminants. Protein tyrosine phosphatase A (PtpA) has been identified as a secreted protein critical for survival of mycobacteria within infected macrophages. The host may mount an immune response to such secreted proteins. In this study, the humoral immune response to purified recombinant M. avium subsp. paratuberculosis PtpA was investigated using sera from a cohort of sheep infected with M. avium subsp. paratuberculosis and compared with uninfected healthy controls. A significantly higher level of reactivity to PtpA was observed in sera collected from M. avium subspecies paratuberculosis infected sheep when compared to those from uninfected healthy controls. PtpA could be a potential candidate antigen for detection of humoral immune responses in sheep infected with M. avium subspecies paratuberculosis.

  8. Complexity.

    PubMed

    Gómez-Hernández, J Jaime

    2006-01-01

    It is difficult to define complexity in modeling. Complexity is often associated with uncertainty since modeling uncertainty is an intrinsically difficult task. However, modeling uncertainty does not require, necessarily, complex models, in the sense of a model requiring an unmanageable number of degrees of freedom to characterize the aquifer. The relationship between complexity, uncertainty, heterogeneity, and stochastic modeling is not simple. Aquifer models should be able to quantify the uncertainty of their predictions, which can be done using stochastic models that produce heterogeneous realizations of aquifer parameters. This is the type of complexity addressed in this article.

  9. Disseminated mycobacteriosis due to Mycobacterium avium in captive Bengal tiger (Panthera tigris).

    PubMed

    Cho, Ho-Seong; Kim, Yong-Hwan; Park, Nam-Yong

    2006-05-01

    A 2-year-old captive female Bengal Tiger (Panthera tigris) died after prolonged anorexia in the Gwangju Uchi Park Zoo, Gwangju, Republic of Korea. Necropsy revealed multiple nodules of varying sizes in the lung, liver, kidney, and spleen. Histopathologic examination revealed a typical granuloma composed of caseous necrotic areas surrounded by lymphocytes with a few giant cells and foamy macrophages. Periodic acid-Schiff stain and Gomori methenamine silver stain did not reveal any fungal bodies. The Ziehl-Neelsen acid-fast stain revealed few acid-fast organisms in the lung, liver, kidney, and spleen. A polymerase chain reaction assay of the lung, liver, kidney, and spleen yielded a positive result for Mycobacterium avium subsp. avium. This is an unusual case of disseminated infection of a wild mammal with avian mycobacteriosis, and is believed to be most likely associated with the feeding of tigers with culled chickens infected with M. avium.

  10. Immunoreactivity of the Mycobacterium avium subsp. paratuberculosis 19-kDa lipoprotein

    PubMed Central

    Huntley, Jason FJ; Stabel, Judith R; Bannantine, John P

    2005-01-01

    Background The Mycobacterium tuberculosis 19-kDa lipoprotein has been reported to stimulate both T and B cell responses as well as induce a number of Th1 cytokines. In order to evaluate the Mycobacterium avium subsp. paratuberculosis (M. avium subsp. paratuberculosis) 19-kDa lipoprotein as an immunomodulator in cattle with Johne's disease, the gene encoding the 19-kDa protein (MAP0261c) was analyzed. Results MAP0261c is conserved in mycobacteria, showing a 95% amino acid identity in M. avium subspecies avium, 84% in M. intracellulare and 76% in M. bovis and M. tuberculosis. MAP0261c was cloned, expressed, and purified as a fusion protein with the maltose-binding protein (MBP-19 kDa) in Escherichia coli. IFN-γ production was measured from 21 naturally infected and 9 control cattle after peripheral blood mononuclear cells (PBMCs) were stimulated with a whole cell lysate (WCL) of M. avium subsp. paratuberculosis or the recombinant MBP-19 kDa. Overall, the mean response to MBP-19 kDa was not as strong as the mean response to the WCL. By comparison, cells from control, non-infected cattle did not produce IFN-γ after stimulation with either WCL or MBP-19 kDa. To assess the humoral immune response to the 19-kDa protein, sera from cattle with clinical Johne's disease were used in immunoblot analysis. Reactivity to MBP-19 kDa protein, but not MBP alone, was observed in 9 of 14 infected cattle. Antibodies to the 19-kDa protein were not observed in 8 of 9 control cows. Conclusions Collectively, these results demonstrate that while the 19-kDa protein from M. avium subsp. paratuberculosis stimulates a humoral immune response and weak IFN-γ production in infected cattle, the elicited responses are not strong enough to be used in a sensitive diagnostic assay. PMID:15663791

  11. Formulation and efficacy of liposome-encapsulated antibiotics for therapy of intracellular Mycobacterium avium infection.

    PubMed Central

    Oh, Y K; Nix, D E; Straubinger, R M

    1995-01-01

    Mycobacterium avium is an intracellular pathogen that can invade and multiply within macrophages of the reticuloendothelial system. Current therapy is not highly effective. Particulate drug carriers that are targeted to the reticuloendothelial system may provide a means to deliver antibiotics more efficiently to M. avium-infected cells. We investigated the formulation of the antibiotics ciprofloxacin and azithromycin in liposomes and tested their antibacterial activities in vitro against M. avium residing within J774, a murine macrophage-like cell line. A conventional passive-entrapment method yielded an encapsulation efficiency of 9% for ciprofloxacin and because of aggregation mediated by the cationic drug, was useful only with liposomes containing < or = 50 mol% negatively charged phospholipid. In contrast, ciprofloxacin was encapsulated with > 90% efficiency, regardless of the content of negatively charged lipids, by a remote-loading technique that utilized both pH and potential gradients to drive drug into preformed liposomes. Both the cellular accumulation and the antimycobacterial activity of ciprofloxacin increased in proportion to the liposome negative charge; the maximal enhancement of potency was 43-fold in liposomes of distearoylphosphatidylglycerol-cholesterol (DSPG-Chol) (10:5). Azithromycin liposomes were prepared as a freeze-dried preparation to avoid chemical instability during storage, and drug could be incorporated at 33 mol% (with respect to phospholipid). Azithromycin also showed enhanced antimycobacterial effect in liposomes, and the potency increased in parallel to the moles percent of negatively charged lipids; azithromycin in DSPG-Chol (10:5) liposomes inhibited intracellular M. avium growth 41-fold more effectively than did free azithromycin. Thus, ciprofloxacin or azithromycin encapsulated in stable liposomes having substantial negative surface charge is superior to nonencapsulated drug in inhibition of M.avium growth within cultured

  12. Identification of immunoreactive proteins of Mycobacterium avium subsp. paratuberculosis.

    PubMed

    Piras, Cristian; Soggiu, Alessio; Bonizzi, Luigi; Greco, Viviana; Ricchi, Matteo; Arrigoni, Norma; Bassols, Anna; Urbani, Andrea; Roncada, Paola

    2015-02-01

    Mycobacterium avium subsp. paratuberculosis (MAP) is the cause of a chronic enteritis of ruminants (bovine paratuberculosis (PTB)--Johne's disease) that is associated with enormous worldwide economic losses for the animal production. Diagnosis is based on observation of clinical signs, the detection of antibodies in milk or serum, or evaluation of bacterial culture from feces. The limit of these methods is that they are not able to detect the disease in the subclinical stage and are applicable only when the disease is already advanced. For this reason, the main purpose of this study is to use the MAP proteome to detect novel immunoreactive proteins that may be helpful for PTB diagnoses. 2DE and 2D immunoblotting of MAP proteins were performed using sera of control cattle and PTB-infected cattle in order to highlight the specific immunoreactive proteins. Among the assigned identifiers to immunoreactive spots it was found that most of them correspond to surface-located proteins while three of them have never been described before as antigens. The identification of these proteins improves scientific knowledge that could be useful for PTB diagnoses. The sequence of the identified protein can be used for the synthesis of immunoreactive peptides that could be screened for their immunoreaction against bovine sera infected with MAP. All MS data have been deposited in the ProteomeXchange consortium with identifier PXD001159 and DOI 10.6019/PXD001159.

  13. Development of vaccines to Mycobacterium avium subsp. paratuberculosis infection

    PubMed Central

    2016-01-01

    Johne's disease or paratuberculosis is a chronic debilitating disease in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). The disease causes significant economic losses in livestock industries worldwide. There are no effective control measures to eradicate the disease because there are no appropriate diagnostic methods to detect subclinically infected animals. Therefore, it is very difficult to control the disease using only test and cull strategies. Vaccination against paratuberculosis has been considered as an alternative strategy to control the disease when combined with management interventions. Understanding host-pathogen interactions is extremely important to development of vaccines. It has long been known that Th1-mediated cellular immune responses are play a crucial role in protection against MAP infection. However, recent studies suggested that innate immune responses are more closely related to protective effects than adaptive immunity. Based on this understanding, several attempts have been made to develop vaccines against paratuberculosis. A variety of ideas for designing novel vaccines have emerged, and the tests of the efficacy of these vaccines are conducted constantly. However, no effective vaccines are commercially available. In this study, studies of the development of vaccines for MAP were reviewed and summarized. PMID:27489800

  14. Control of Mycobacterium avium subsp. paratuberculosis infection in agricultural species.

    PubMed

    Kennedy, D J; Benedictus, G

    2001-04-01

    Paratuberculosis or Johne's disease is a chronic intestinal disease caused by Mycobacterium avium subsp. paratuberculosis, which continues to spread in agricultural species. Control of paratuberculosis is challenging and should not be underestimated. Due to the long incubation period of the infection, disease is largely subclinical in domesticated livestock. Hence, direct effects on animal productivity and welfare are often masked and may appear insufficient to justify large investments in control programmes by individual farmers, livestock industries or governments. Furthermore, in some countries the main effects of the disease are indirect, resulting from the impact of market discrimination against herds and flocks known to be infected, or from the control measures enforced to reduce transmission. In such circumstances, producers may be unwilling to co-operate with surveillance that may detect infection in herds or flocks. As control programmes are rarely successful in eliminating the infection from a herd or flock in the short term without an aggressive and costly programme, financial and community support assists producers to deal with the challenge. Successful prevention and control depends on animal health authorities and livestock industries acquiring a good understanding of the nature and epidemiology of infection, and of the application of tools for diagnosis and control. Building support for control programmes under the leadership of the affected livestock industries is critical, as programmes are unlikely to be successful without ongoing political will, supported by funding for research, surveillance and control.

  15. Ascorbic acid metabolism during sweet cherry (Prunus avium) fruit development

    PubMed Central

    Ni, Zhiyou; Lin, Lijin; Tang, Yi; Wang, Zhihui; Wang, Xun; Wang, Jin; Lv, Xiulan; Xia, Hui

    2017-01-01

    To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium ‘Hongdeng’), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit. PMID:28245268

  16. Peptides specific for Mycobacterium avium subspecies paratuberculosis infection: diagnostic potential.

    PubMed

    Casey, J L; Sanalla, A M; Tamvakis, D; Thalmann, C; Carroll, E L; Parisi, K; Coley, A M; Stewart, D J; Vaughan, J A; Michalski, W P; Luke, R; Foley, M

    2011-08-01

    Mycobacterium avium subspecies paratuberculosis (Map) is the causative agent of Johne's disease (JD). Current serological diagnostic tests for JD are limited by their sensitivity when used in sub-clinical stages of the disease. Our objective was to identify peptides that mimic diagnostically important Map epitopes that might be incorporated into a new-generation JD diagnostic. Four peptides were isolated from a phage-displayed random peptide library by screening on antibodies derived from Map-infected goats. The peptides were recognised by antibodies from Map-infected goats but not by antibodies from uninfected goats. The peptides elicited immune responses in rabbits, which reacted strongly with bona fide Map antigens proving the peptides were true epitope mimics. To assess the diagnostic value a panel of goat sera was screened for reactivity's with peptides. The peptides were recognised by antibodies from a proportion of goats infected with Map compared with control animals with a diagnostic specificity of 100% and the sensitivity ranged from 50 to 75%. Combinations of any two peptides improved sensitivity 62.5-87.5% and 100% sensitivity was achieved with three of the four peptides in combination. These data suggest peptides representing diagnostically important Map epitopes could be incorporated into a sensitive diagnostic test.

  17. Mycobacterium avium subsp. paratuberculosis: pathogen, pathogenesis and diagnosis.

    PubMed

    Manning, E J; Collins, M T

    2001-04-01

    Johne's disease, or paratuberculosis, is a chronic intestinal infection caused by Mycobacterium avium subsp. paratuberculosis. The usually fatal disease is characterised by cachexia, and in some species diarrhoea, after a long pre-clinical phase. Treatment is ineffective and economically impracticable. The infection primarily affects domestic and free-ranging ruminants, but has also been reported in primates, rabbits, stoats and foxes. Since paratuberculosis is often subclinical, under-reporting is suspected, even though the disease is notifiable in numerous countries. Herd prevalence of bovine paratuberculosis in Europe ranges from 7% to 55%. In the United States of America, herd prevalence is strongly associated with herd size; 40% of herds of more than 300 head were found to be infected. In Australia, reported dairy herd infection rates range between 9% and 22%. Paratuberculosis in domestic livestock entails significant economic losses due to several factors (e.g. reduced production, premature culling and increased veterinary costs). Free-ranging and captive wildlife are also at risk from paratuberculosis.

  18. Ascorbic acid metabolism during sweet cherry (Prunus avium) fruit development.

    PubMed

    Liang, Dong; Zhu, Tingting; Ni, Zhiyou; Lin, Lijin; Tang, Yi; Wang, Zhihui; Wang, Xun; Wang, Jin; Lv, Xiulan; Xia, Hui

    2017-01-01

    To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium 'Hongdeng'), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit.

  19. Identification of members of Mycobacterium avium species by Accu-Probes, serotyping, and single IS900, IS901, IS1245 and IS901-flanking region PCR with internal standards.

    PubMed

    Bartos, Milan; Hlozek, Pavel; Svastova, Petra; Dvorska, Lenka; Bull, Tim; Matlova, Ludmila; Parmova, Ilona; Kuhn, Isolde; Stubbs, Janine; Moravkova, Monika; Kintr, Jaromir; Beran, Vladimir; Melicharek, Ivan; Ocepek, Matjaz; Pavlik, Ivo

    2006-03-01

    From Mycobacterium avium species Mycobacterium avium subsp. paratuberculosis (n=961), Mycobacterium a. avium (n=677), Mycobacterium a. silvaticum (n=5), and Mycobacterium a. hominissuis (n=1566) were examined, and from Mycobacterium tuberculosis complex M. tuberculosis (n=2), Mycobacterium bovis (n=13), M. bovis BCG (n=4), and Mycobacterium caprae (n=10) were examined. From other mycobacterial species Mycobacterium intracellulare (n=60) and atypical mycobacteria (n=256) including Mycobacterium fortuitum, Mycobacterium chelonae, Mycobacterium scrofulaceum, Mycobacterium gastri and other species of conditionally pathogenic mycobacteria were analysed. The internal standard molecules corresponding to insertion sequences IS900, IS901, IS1245, and flanking region (FR300) of IS901 were produced by PCR of alfalfa genome segment and inserted into plasmid vector. The resulting recombinant plasmid molecules were used as internal standards in coamplification with a total of 4729 mycobacterial collection strains and field isolates between 1996 and 2003. The size differences between amplicons obtained from IS900 (258 bp), IS901 (1108 bp), IS1245 (427 bp), and FR300 (300 bp) and from corresponding internal standard molecules ISIS900 (591 bp), ISIS901 (1 336 bp), ISIS1245 (583 bp), and IS901 flanking region of 300 bp ISFR300 (488 bp), respectively, allowed easy discrimination. The internal amplicons were visible by naked aye on agarose gel when 10(1), 10(3), 10(2), and 10(2) molecules for ISIS900, ISIS901, ISIS1245, and ISFR300 were used in the PCR, respectively, when no bacterial DNA was added to the reaction. The system was tested to define the amount of internal standards that could be used in the PCR without affecting the amplification of the specific segment. Non-specific amplifications were observed in M. fortuitum with IS1245 PCR and mixed infections with M. a. avium and M. a. hominissuis from pigs and cattle were found. PCR results of typing were compared with serotyping

  20. Capacity is the Wrong Paradigm

    DTIC Science & Technology

    2002-01-01

    Florida Gainesville, FL 32611-6120 ABSTRACT At present, \\capacity" is the prevailing paradigm for covert channels. With respect to steganography ...INTRODUCTION Steganography is the art and science of sending a hidden message from Alice to Bob, so that an eavesdropper is not aware that this hidden...discussed a di erent new paradigm con- cerning steganography . The concern of that new paradigm was \\when is something discovered." We feel that both

  1. The WIMP Paradigm: Current Status

    SciTech Connect

    Feng, Jonathan

    2011-03-23

    The WIMP paradigm is the glue that joins together much of the high energy and cosmic frontiers. It postulates that most of the matter in the Universe is made of weakly-interacting massive particles, with implications for a broad range of experiments and observations. I will review the WIMP paradigm's underlying motivations, its current status in view of rapid experimental progress on several fronts, and recent theoretical variations on the WIMP paradigm theme.

  2. The Peter Pan paradigm.

    PubMed

    Cohen, J Craig; Larson, Janet E

    2008-01-08

    Genetic and environmental agents that disrupt organogenesis are numerous and well described. Less well established, however, is the role of delay in the developmental processes that yield functionally immature tissues at birth. Evidence is mounting that organs do not continue to develop postnatally in the context of these organogenesis insults, condemning the patient to utilize under-developed tissues for adult processes. These poorly differentiated organs may appear histologically normal at birth but with age may deteriorate revealing progressive or adult-onset pathology. The genetic and molecular underpinning of the proposed paradigm reveals the need for a comprehensive systems biology approach to evaluate the role of maternal-fetal environment on organogenesis."You may delay, but time will not" Benjamin Franklin, USA Founding Father.

  3. PD-L2 induction on dendritic cells exposed to Mycobacterium avium downregulates BCG-specific T cell response.

    PubMed

    Mendoza-Coronel, Elizabeth; Camacho-Sandoval, Rosa; Bonifaz, Laura C; López-Vidal, Yolanda

    2011-01-01

    The exposure to certain species of Nontuberculous Mycobacteria (NTM) can modulate the immune response induced by Mycobacterium bovis BCG. Mycobacterium avium has been postulated as a weak inducer of dendritic cell (DC) maturation. However, how the DC exposure to M. avium could contribute to the modulation of a BCG-specific CD4+ T cell response and the molecules involved remain unknown. Here, we exposed bone marrow-derived DCs (BMDCs) to M. avium either prior to exposure to BCG or as a unique stimulus. We found that M. avium induces high expression of PD-L2 (B7-DC) in BMDCs. This was dependent on IL-10 production through the TLR2-p38 MAPK signaling pathway. Exposure to M. avium prior to BCG results in BMDCs that do not express co-stimulatory molecules and pro-inflammatory cytokines, while the expression of PD-L2 and IL-10 was maintained. BMDCs exposed to M. avium impaired the activation of BCG-specific T cells through the PD-1: PD-L interaction. This suggests that a M. avium-induced phenotype in DCs might be implicated in the induction of mechanisms of tolerance that could impact the T cell response induced by BCG vaccination.

  4. Paradigms for parasite conservation.

    PubMed

    Dougherty, Eric R; Carlson, Colin J; Bueno, Veronica M; Burgio, Kevin R; Cizauskas, Carrie A; Clements, Christopher F; Seidel, Dana P; Harris, Nyeema C

    2016-08-01

    Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite-inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid-20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host-density threshold and cost-benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host-parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of

  5. In Vivo Volatile Organic Compound Signatures of Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Bergmann, Andreas; Trefz, Phillip; Fischer, Sina; Klepik, Klaus; Walter, Gudrun; Steffens, Markus; Ziller, Mario; Schubert, Jochen K.; Reinhold, Petra; Köhler, Heike; Miekisch, Wolfram

    2015-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of a chronic enteric disease of ruminants. Available diagnostic tests are complex and slow. In vitro, volatile organic compound (VOC) patterns emitted from MAP cultures mirrored bacterial growth and enabled distinction of different strains. This study was intended to determine VOCs in vivo in the controlled setting of an animal model. VOCs were pre-concentrated from breath and feces of 42 goats (16 controls and 26 MAP-inoculated animals) by means of needle trap microextraction (breath) and solid phase microextraction (feces) and analyzed by gas chromatography/ mass spectrometry. Analyses were performed 18, 29, 33, 41 and 48 weeks after inoculation. MAP-specific antibodies and MAP-specific interferon-γ-response were determined from blood. Identities of all marker-VOCs were confirmed through analysis of pure reference substances. Based on detection limits in the high pptV and linear ranges of two orders of magnitude more than 100 VOCs could be detected in breath and in headspace over feces. Twenty eight substances differed between inoculated and non-inoculated animals. Although patterns of most prominent substances such as furans, oxygenated substances and hydrocarbons changed in the course of infection, differences between inoculated and non-inoculated animals remained detectable at any time for 16 substances in feces and 3 VOCs in breath. Differences of VOC concentrations over feces reflected presence of MAP bacteria. Differences in VOC profiles from breath were linked to the host response in terms of interferon-γ-response. In a perspective in vivo analysis of VOCs may help to overcome limitations of established tests. PMID:25915653

  6. Antemortem and postmortem examinations of the cattle calf naturally infected with Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Appana, Gangadhararao; Das, Dipankar; Veerasami, Maroudam; Senthilkumar, Ramachandran Lakshmikanthan; Durishetty, Munishkumar; Ramalakshmi, B.; Bahekar, Vijay; Mukherjee, Falguni; Chandran, Dev; Kumar, P. Uday; Sesikeran, B.

    2013-01-01

    A male cattle calf was detected as subclinically and naturally infected with Mycobacterium avium subspecies paratuberculosis (MAP) by a series of antemortem and postmortem tests. The MAP infection was identified by strong antibody and cell-mediated immune (CMI) response by a commercial ELISA kit and an intradermal Johnin test, respectively, in the initial antemortem examination. The antemortem status of the calf was further confirmed by MAP-specific interferon gamma (IFN-γ) response. For detection of IFN-γ response, MAP-specific IFN-γ release assays (IGRAs): (a) immuno capture ELISA (IC-ELISA) and (b) ELISPOT was employed. In addition, the presence of intracellular cytokine IFN-γ was detected by flow cytometry. For all cytokine assays, MAP-specific recombinant antigens HSP65 and 35 kDa were employed to overcome the poor sensitivity and specificity resulting from the use of Johnin, the crude protein purified derivative of MAP. Postmortem examination of the MAP-infected/suspected cattle calf did not reveal any pathognomonic gross lesions in the gastro-intestinal tract. Histopathological examination of multiple organs showed the presence of epithelioid cells/macrophages and edematous lesions in the mesenteric lymph nodes suggestive of MAP; however, no granulomas were observed in the intestinal tract. The necropsy samples of rectum and mesenteric lymph nodes were positive for isolation of MAP by culture in the BACTEC™ MGIT™ 960 system, and acid fast bacilli were demonstrated by fluorescence microscopy confirming the infection. Due to differential and complex expression patterns of MAP antigens reported in literature, a combination of assays such as those based on IGRAs and antibody detection is essential. Therefore, the current experimental evidence confirms the efficacy of the approach adopted. However, further studies will be needed to understand the optimal combination MAP-specific antigens for use in IGRAs or antibody assays that can be used for detecting

  7. Surveillance system sensitivities and probability of freedom from Mycobacterium avium subsp. paratuberculosis infection in Swedish cattle.

    PubMed

    Frössling, Jenny; Wahlström, Helene; Agren, Estelle Carina Constance; Cameron, Angus; Lindberg, Ann; Sternberg Lewerin, Susanna

    2013-01-01

    Previous investigations suggest that the prevalence of Mycobacterium avium subsp. paratuberculosis (MAP) in Swedish cattle is low and all recent cases have been linked to imported animals. The aim of this study was to evaluate the surveillance system for MAP infection in Swedish cattle and to estimate the probability that the Swedish cattle population is free from this infection. Calculations of surveillance sensitivities and probability of freedom were made using stochastic scenario-tree modelling, which allows inclusion of information from several different sources, of complex surveillance data including results from non-representative sampling, as well as of documentations of differences in risk of being infected. The surveillance components included in the model were: (1) clinical surveillance, (2) fallen stock investigations, (3) the national surveillance programme (mainly beef herds), (4) a survey involving dairy herds and (5) a risk-based survey targeting herds with imported cattle. Previous or current presence of imported animals and participation in the on-going control programme was specified for each tested herd, in order to adjust for differences in risk. Calculations were made for each year from the start of 2005 to the end of 2008, and this formed the basis for a final estimate covering the whole study period and predictions of future probabilities of freedom from MAP. Results show that when applying a design prevalence of one animal in 0.1% of the herds, the probability of freedom at the end of 2008 was 0.63. At the design prevalence of one animal in 0.5% of herds, the estimated probability is >95% and it is demonstrated that the prevalence of MAP in Swedish cattle is below this level or absent. In order to increase the annual surveillance sensitivity in the future and thereby improve the probability of freedom, new surveillance activities or an intensification of current ones are needed.

  8. A randomized, double-blind trial comparing azithromycin and clarithromycin in the treatment of disseminated Mycobacterium avium infection in patients with human immunodeficiency virus.

    PubMed

    Dunne, M; Fessel, J; Kumar, P; Dickenson, G; Keiser, P; Boulos, M; Mogyros, M; White Jr, A C; Cahn, P; O'Connor, M; Lewi, D; Green, S; Tilles, J; Hicks, C; Bissett, J; Schneider, M M; Benner, R

    2000-11-01

    Two hundred and forty-six patients infected with human immunodeficiency virus (HIV) who also had disseminated Mycobacterium avium complex received either azithromycin 250 mg every day, azithromycin 600 mg every day, or clarithromycin 500 mg twice a day, each combined with ethambutol, for 24 weeks. Samples drawn from patients were cultured and clinically assessed every 3 weeks up to week 12, then monthly thereafter through week 24 of double-blind therapy and every 3 months while on open-label therapy through the conclusion of the trial. The azithromycin 250 mg arm of the study was dropped after an interim analysis showed a lower rate of clearance of bacteremia. At 24 weeks of therapy, the likelihood of patients' developing 2 consecutive negative cultures (46% vs. 56%, P=.24) or 1 negative culture (59% vs. 61%, P=.80) was similar for azithromycin 600 mg (n=68) and clarithromycin (n=57), respectively. The likelihood of relapse was 39% versus 27% (P=.21) on azithromycin compared with clarithromycin, respectively. Of the 6 patients who experienced relapse, none of those randomized to receive azithromycin developed isolates resistant to macrolides, compared with 2 of 3 patients randomized to receive clarithromycin [corrected]. Mortality was similar in patients comprising each arm of the study (69% vs. 63%; hazard, 95.1% confidence interval, 1.1 [0.7, 1.7]). Azithromycin 600 mg, when given in combination with ethambutol, is an effective agent for the treatment of disseminated M. avium disease in patients infected with HIV.

  9. Bioactive components of Prunus avium L. black gold (red cherry) and Prunus avium L. stark gold (white cherry) juices, wines and vinegars.

    PubMed

    Budak, Nilgün H

    2017-01-01

    Cherries are one of the most popular fruits, characterized by attractive colour, firmness, appearance and delicious tastes. Cherries are consumed fresh as well as in jams, wine, dried, candy and other processed products. Cherries vary in antioxidant properties and phenolic substances. The aim of the study was to determine the effects of ethanol and acetic acid fermentation on total antioxidant activities and phenolic substances of cherry juice. Total investigation of solids, pH, soluble solids, phenolic substances, ORAC and TEAC of Prunus avium L. cherry juices, macerated cherries wine, and vinegars were analyzed. All samples had 300.1-854.79 mg GAE/L of total phenolic contents, and 6.62-17.97 µmol/mL of ORAC values, and 1.5-5.5 mmol/mL of TEAC. Chlorogenic acid was present in the highest amount P. avium L. black gold vinegar.

  10. Association of ISMav6 with the Pattern of Antibiotic Resistance in Korean Mycobacterium avium Clinical Isolates but No Relevance between Their Genotypes and Clinical Features

    PubMed Central

    Kim, Su-Young; Jeong, Byeong-Ho; Park, Hye Yun; Jeon, Kyeongman; Han, Seung Jung; Shin, Sung Jae; Koh, Won-Jung

    2016-01-01

    The aim of this study was to genetically characterize clinical isolates from patients diagnosed with Mycobacterium avium lung disease and to investigate the clinical significance. Multi-locus sequencing analysis (MLSA) and pattern of insertion sequence analysis of M. avium isolates from 92 Korean patients revealed that all isolates were M. avium subspecies hominissuis. In hsp65 sequevar analysis, codes 2, 15, and 16 were most frequently found (88/92) with similar proportions among cases additionally two isolates belonging to code N2 and an unreported code were identified, respectively. In insertion element analysis, all isolates were IS1311 positive and IS900 negative. Four of the M. avium subsp. hominissuis isolates did not harbor IS1245 and 1 of the M. avium isolates intriguingly harbored DT1, which is thought to be a M. intracellulare-specific element. M. avium subsp. hominissuis harboring ISMav6 is prevalent in Korea. No significant association between clinical manifestation and treatment response has been found in patients with the hsp65 code type and ISMav6, indicating that no specific strain/genotype among M. avium subsp. hominissuis organisms was a major source of M. avium lung disease. Interestingly, the presence of ISMav6 was correlated with greater resistance to moxifloxacin. Conclusively, the genotype of Korean M. avium subsp. hominissuis isolates is not a disease determinant responsible for lung disease and specific virulent factors of M. avium subsp. hominissuis need to be investigated further. PMID:26859598

  11. Phagosome-lysosome fusions in macrophages infected by Mycobacterium avium: role of mycosides-C and other cells surface components.

    PubMed

    Fréhel, C; Rastogi, N

    1989-01-01

    The phagosome-lysosome fusions (PLE) were assessed in case of bone-marrow macrophages infected by the opportunistic species Mycobacterium avium, employing the acid-phosphatase (AcPase) electron-cytochemistry. The role of surface components was evaluated by coating the bacteria prior to phagocytosis by specific M. avium antiserum or the anti-mycosides-C serum raised in rabbit. PLF was evaluated under the electron microscope during (2, 4 hours), or after (24 hours) phagocytosis. The preliminary results suggest that although M. avium surface components intervene in PLF inhibition, the role of mycosides-C among these surface components (effectively intervening in PLF inhibition) is questionable.

  12. Naturalistic Inquiry: Paradigm and Method.

    ERIC Educational Resources Information Center

    Lotto, Linda S.

    Despite the rhetoric acclaiming it as a new paradigm, educational researchers have tended to treat naturalistic inquiry as a new or alternative method employed within the dominant, rationalistic paradigm. Spokespersons for naturalistic inquiry tend to concentrate on what one does differently rather than how one perceives what one is doing…

  13. Human Nature and Research Paradigms: Theory Meets Physical Therapy Practice

    ERIC Educational Resources Information Center

    Plack, Margaret M.

    2005-01-01

    Human nature is a very complex phenomenon. In physical therapy this complexity is enhanced by the need to understand the intersection between the art and science of human behavior and patient care. A paradigm is a set of basic beliefs that represent a worldview, defines the nature of the world and the individual's place in it, and helps to…

  14. Bordetella avium causes induction of apoptosis and nitric oxide synthase in turkey tracheal explant cultures.

    PubMed

    Miyamoto, David M; Ruff, Kristin; Beach, Nathan M; Stockwell, Stephanie B; Dorsey-Oresto, Angella; Masters, Isaac; Temple, Louise M

    2011-09-01

    Bordetellosis is an upper respiratory disease of turkeys caused by Bordetella avium in which the bacteria attach specifically to ciliated respiratory epithelial cells. Little is known about the mechanisms of pathogenesis of this disease, which has a negative impact in the commercial turkey industry. In this study, we produced a novel explant organ culture system that was able to successfully reproduce pathogenesis of B. avium in vitro, using tracheal tissue derived from 26 day-old turkey embryos. Treatment of the explants with whole cells of B. avium virulent strain 197N and culture supernatant, but not lipopolysaccharide (LPS) or tracheal cytotoxin (TCT), specifically induced apoptosis in ciliated cells, as shown by annexin V and TUNEL staining. LPS and TCT are known virulence factors of Bordetella pertussis, the causative agent of whooping cough. Treatment with whole cells of B. avium and LPS specifically induced NO response in ciliated cells, shown by uNOS staining and diaphorase activity. The explant system is being used as a model to elucidate specific molecules responsible for the symptoms of bordetellosis.

  15. Immunlogic responses to Mycobacterium avium subsp. paratuberculosis protein cocktail vaccines in a mouse model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease is a chronic granulomatous enteritis characterized by severe diarrhea, wasting, and a decline in milk production caused by the bacterium Mycobacterium avium subsp. paratuberculosis (MAP). The vaccine currently on the market has some limitations including a severe injection site react...

  16. Immunologic responses to Mycobacterium avium subsp. paratuberculois protein cocktail vaccines in a mouse model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease is a chronic granulomatous enteritis characterized by severe diarrhea, wasting and a decline in milk production caused by the bacterium Mycobacterium avium subsp. paratuberculois (MAP). The vaccine currently on the market has some limitations including a severe injection site reactio...

  17. High-polarity Mycobacterium avium-derived lipids interact with murine macrophage lipid rafts.

    PubMed

    Maldonado-García, G; Chico-Ortiz, M; Lopez-Marin, L M; Sánchez-García, F J

    2004-11-01

    Cholesterol- and sphingolipid-rich membrane microdomains (lipid rafts) are widely recognized as portals for pathogenic micro-organisms. A growing body of evidence demonstrates mobilization of host plasma cell membrane lipid rafts towards the site of contact with several pathogens as well as a strict dependence on cholesterol for appropriate internalization. The fate of lipid rafts once the pathogen has been internalized and the nature of the pathogen components that interact with them is however less understood. To address both these issues, infection of the J774 murine cell line with Mycobacterium avium was used as a model. After demonstrating that M. avium induces lipid raft mobilization and that M. avium infects J774 by a cholesterol-dependent mechanism, it is shown here that mycobacterial phagosomes harbour lipid rafts, which are, at least in part, of plasma cell membrane origin. On the other hand, by using latex microbeads coated with any of the three fractions of M. avium-derived lipids of different polarity, we provide evidence that high-polarity, in contrast to low-polarity and intermediate-polarity, mycobacterial lipids or uncoated latex beads have a strong capacity to induce lipid raft mobilization. These results suggest that high-polarity mycobacterial lipid(s) interact with host cell cholesterol-enriched microdomains which may in turn influence the course of infection.

  18. Functional Characterization of Iron Dependent Regulator (IdeR) of Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study we investigated an iron dependent regulator (IdeR) of Mycobacterium avium subsp. paratuberculosis (MAP). IdeR is a transcriptional factor that plays a global iron regulatory role in Mycobacterium tuberculosis (MTB) with a 19-bp recognition sequence. IdeR recognition sites within MAP ge...

  19. COMPARISON OF MYCOBACTERIUM AVIUM ISOLATES FROM DRINKING WATER AND FROM THE POPULATION SERVED BY THE SYSTEM

    EPA Science Inventory

    Background: Current evidence suggests that drinking water, soil, and produce are potential sources of Mycobacterium avium infections, a pathogen not known to be transmitted person-to-person.

    Methods: We sampled water during 2000 - 2002 from a large municipal drinking wate...

  20. Optimization of hexadecylpyridinium chloride decontamination for culture of Mycobacterium avium subsp. paratuberculosis from milk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cows in advanced stages of Johne’s disease shed Mycobacterium avium subsp. paratuberculosis (MAP) into both their milk and feces, allowing for transmission of the bacteria between animals. The objective of this study was to formulate an optimized protocol for the isolation of MAP from milk and colos...

  1. Primary transcriptomes of Mycobacterium avium subsp. paratuberculosis reveal proprietary pathways in tissue and macrophages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Mycobacterium avium subsp. paratuberculosis persistently infect intestines and mesenteric lymph nodes leading to a prolonged subclinical disease. We investigated the intracellular lifestyle of MAP in the intestines and lymph nodes to understand the MAP pathways that function to govern th...

  2. Iron-sparing Response of Mycobacterium avium subsp. paratuberculosis is Strain Dependent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Two genotypically and microbiologically distinct strains of Mycobacterium avium subsp. paratuberculosis (MAP) exist – the type I and type II strains that primarily infect sheep and cattle, respectively. Concentration of iron in the cultivation medium has been suggested as one contributin...

  3. Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be the primary source of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-se...

  4. Characteristics of an Extensive Mycobacterium avium subspecies paratuberculosis Recombinant Protein Set

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the first step of a comprehensive large-scale antigen discovery project, 651 Mycobacterium avium subspecies paratuberculosis proteins were produced in Escherichia coli. All of these were purified by affinity chromatography, dialyzed in phosphate buffered saline, and analyzed on SDS-PAGE gels. C...

  5. Immunologic Responses to Mycobacterium avium subsp. paratuberculosis in Neonatal Calves After Oral or Intraperitoneal Experimental Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection models are useful for studying host responses to infection to aid in the development of diagnostic tools and vaccines. The majority of experimental models for ruminants have utilized an oral inoculation of live Mycobacterium avium subsp. paratuberculosis (MAP) in order to establish infecti...

  6. Induction of B Cell Responses Upon Experimental Infection of Neonatal Calves with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal models are useful for studying host responses to infection and aid in the development of diagnostic tools and vaccines. The current study was designed to compare the effects of different methods of experimental infection: Oral (Mycobacterium avium subsp. parauberculosis (MAP) strain K-10; Or...

  7. Induction of B Cell Responses upon Experimental Infection of Neonatal Calves with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal models are useful for studying host responses to infection and aid in the development of diagnostic tools and vaccines. The current study was designed to compare the effects of different methods of experimental infection: Oral (Mycobacterium avium subsp. parauberculosis (MAP) strain K-10; Or...

  8. Pathogenesis of Mycobacterium avium subsp. paratuberculosis in Neonatal Calves after Oral or Intraperitoneal Experimental Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the infection process to Mycobacterium avium subsp. paratuberculosis is tantamount to the development of effective vaccines and therapeutics for the control of this disease in the field. The current study compared the effectiveness of oral and intraperitoneal methods of experimental in...

  9. Detection of Mycobacterium avium subspecies paratuberculosis in Drinking Water and Biofilms Using Quantitative PCR

    EPA Science Inventory

    Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne’s disease in domestic animals and has been implicated in Crohn’s disease in humans. This bacterium is a slow growing, gram-positive, acid-fast organism which can be difficult to culture from the environment. For ...

  10. Lymphoproliferative and gamma interferon responses to stress-regulated Mycobacterium avium subsp. paratuberculosis recombinant proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease in ruminants is a chronic infection of the intestines caused by Mycobacterium avium subsp. paratuberculosis. Economic losses associated with Johne’s disease arise due to premature culling, reduced production of milk and wool and mortalities. The disease is characterised by a long inc...

  11. From mouth to macrophage: mechanisms of innate immune subversion by Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease (JD) is a chronic enteric infection of cattle caused by Mycobacterium avium subsp. paratuberculosis (MAP). The high economic cost and potential zoonotic threat of JD have driven efforts to develop tools and approaches to effectively manage this disease within livestock herds. Efforts...

  12. Transcriptional profiling of ileocecal valve of holstein dairy cows infected with mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease is a chronic infection of the small intestine caused by Mycobacterium avium subspecies paratuberculosis (MAP), an intracellular bacterium. The events of pathogen survival within the host cell(s), chronic inflammation and the progression from asymptomatic subclinical stage to an advan...

  13. CD4 T Cell Dependent Colitis Exacerbation Following Re-Exposure of Mycobacterium avium ssp. paratuberculosis

    PubMed Central

    Suwandi, Abdulhadi; Bargen, Imke; Pils, Marina C.; Krey, Martina; Zur Lage, Susanne; Singh, Anurag K.; Basler, Tina; Falk, Christine S.; Seidler, Ursula; Hornef, Mathias W.; Goethe, Ralph; Weiss, Siegfried

    2017-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic inflammatory bowel disease of cattle characterized by intermittent to chronic diarrhea. In addition, MAP has been isolated from Crohn's disease (CD) patients. The impact of MAP on severity of clinical symptoms in JD as well as its role in CD are yet unknown. We have previously shown that MAP is able to colonize inflamed enteric tissue and to exacerbate the inflammatory tissue response (Suwandi et al., 2014). In the present study, we analyzed how repeated MAP administration influences the course of dextran sulfate sodium (DSS)-induced colitis. In comparison to mice exposed to DSS or MAP only, repeated exposure of DSS-treated mice to MAP (DSS/MAP) revealed a significantly enhanced clinical score, reduction of colon length as well as severe CD4+ T cell infiltration into the colonic lamina propria. Functional analysis identified a critical role of CD4+ T cells in the MAP-induced disease exacerbation. Additionally, altered immune responses were observed when closely related mycobacteria species such as M. avium ssp. avium and M. avium ssp. hominissuis were administered. These data reveal the specific ability of MAP to aggravate intestinal inflammation and clinical symptoms. Overall, this phenotype is compatible with similar disease promoting capabilites of MAP in JD and CD. PMID:28361039

  14. Mycobacterium avium subspecies paratuberculosis recombinant proteins modulate antimycobacterial functions of bovine macrophages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has been shown that Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) activates the Mitogen Activated Protein Kinase (MAPK) p38 pathway, yet it is unclear which components of M. paratuberculosis are involved in the process. Therefore, a set of 42 M. paratuberculosis recombinan...

  15. Shared Mycobacterium avium genotypes observed among unlinked clinical and environmental isolates*

    EPA Science Inventory

    Our understanding of the sources of Mycobacterium avium infection is partially based on genotypic matching of pathogen isolates from cases and environmental sources. These approaches assume that genotypic identity is rare in isolates from unlinked cases or sources. To test this a...

  16. Shared Mycobacterium avium genotypes observed among unlinked clinical and environmental isolates

    EPA Science Inventory

    Our understanding of the sources of Mycobacterium avium infection is partially based on genotypic matching of pathogen isolates from cases and environmental sources. These approaches assume that genotypic identity is rare in isolates from unlinked cases or sources. To test this, ...

  17. Surface Proteome of “Mycobacterium avium subsp. hominissuis” during the Early Stages of Macrophage Infection

    PubMed Central

    McNamara, Michael; Tzeng, Shin-Cheng; Maier, Claudia; Zhang, Li

    2012-01-01

    “Mycobacterium avium subsp. hominissuis” is a robust and pervasive environmental bacterium that can cause opportunistic infections in humans. The bacterium overcomes the host immune response and is capable of surviving and replicating within host macrophages. Little is known about the bacterial mechanisms that facilitate these processes, but it can be expected that surface-exposed proteins play an important role. In this study, the selective biotinylation of surface-exposed proteins, streptavidin affinity purification, and shotgun mass spectrometry were used to characterize the surface-exposed proteome of M. avium subsp. hominissuis. This analysis detected more than 100 proteins exposed at the bacterial surface of M. avium subsp. hominissuis. Comparisons of surface-exposed proteins between conditions simulating early infection identified several groups of proteins whose presence on the bacterial surface was either constitutive or appeared to be unique to specific culture conditions. This proteomic profile facilitates an improved understanding of M. avium subsp. hominissuis and how it establishes infection. Additionally, surface-exposed proteins are excellent targets for the host adaptive immune system, and their identification can inform the development of novel treatments, diagnostic tools, and vaccines for mycobacterial disease. PMID:22392927

  18. Detection of Mycobacterium avium subsp. paratuberculosis in Drinking Water and Biofilms Using Quantitative PCR

    EPA Science Inventory

    Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne’s disease in domestic animals and has been implicated in Crohn’s disease in humans. Cows infected with Johne’s disease shed large quantities of MAP into soil. Further, MAP has been isolated from surface water, is resi...

  19. Assessment of Food as a Source of Exposure to Mycobacterium avium Subspecies Paratuberculosis (MAP)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Advisory Committee on Microbiological Criteria for Foods (NACMCF or Committee) was asked to assess the importance of food as a source of exposure to Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne’s disease, which affects primarily the small intestin...

  20. Osteopontin Expression in Periparturient Dairy Cows Naturally Infected with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease (JD), caused by Mycobacterium avium subsp. paratuberculosis (MAP), is estimated to infect more than 22% of US dairy herds. Periods of immunosuppression, typically seen at parturition, may contribute to the transition from the subclinical, or asymptomatic, to the clinical stage of inf...

  1. Comparison of fecal DNA extraction kits for the detection of Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fecal culture is considered the gold standard for the diagnostics of paratuberculosis, however, PCR for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in fecal material is widely used today, having demonstrated great sensitivity and specificity. To insure the most efficient and r...

  2. Comparison of fecal DNA extraction kits for the detection of Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fecal culture is considered the gold standard for the diagnosis of paratuberculosis, however, PCR for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in fecal material is widely used today, having demonstrated great sensitivity and specificity. To insure the most efficient and rep...

  3. Survival of Mycobacterium avium subsp. paratuberculosis in Biofilms on Livestock Watering Trough Materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the ubiquitous occurrence of Mycobacterium sp. in nature and the fact that Johne’s disease has been reported worldwide, little research has been done to assess the survival of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) in agricultural environments. The goal of this stu...

  4. A new paradigm for geosciences information management

    SciTech Connect

    Bolivar, Stephen L.; Nasser, K.; Dorries, A. M.; Canepa, Julie Ann

    2002-01-01

    Over the past two decades, geoscientists have been increasingly engaged in providing answers to complex environmental problems with significant societal, political, and economic consequences. Today, these scientists have to perform under increasingly greater visibility to stakeholders and the general public. Their activities are much more scrutinized with regards to economic pressure, litigation support and regulatory compliance than in the past. Their current work is built on decades of past work and in many cases will continue for decades to come. Stakeholders are increasingly evaluating raw data rather than just examining summaries in final reports. They also need assurance that proper data control and data quality procedures were followed. Geoscientists are now faced with a new paradigm, i.e. with the challenge of cost effectively collecting, managing, analyzing, and synthesizing enormous volumes of multidisciplinary and complex information. In addition, these data must be processed and disseminated in a way that allows the public to make informed and rational assessments on decisions that are proposed or have been made. The new paradigm is clear - client and stakeholder needs must be better met, and the systems used to store and generate data must meet these needs. This paper addresses the challenges and the implications of this new paradigm on geosciences information management in the 21st Century. It concludes with a case study for a successful implementation of the new paradigm in an environmental restoration project at the Los Alamos National Laboratory (LANL) that is operated by the Department of Energy (DOE). LANL is upgrading and reengineering its data and business processes to better address client, user and stakeholder issues regarding data accessibility, control and quality.

  5. A Rapid Method for Quantifying Viable Mycobacterium avium subsp. paratuberculosis in Cellular Infection Assays

    PubMed Central

    Pooley, Hannah B.; de Silva, Kumudika; Purdie, Auriol C.; Begg, Douglas J.; Whittington, Richard J.

    2016-01-01

    ABSTRACT Determining the viability of bacteria is a key outcome of in vitro cellular infection assays. Currently, this is done by culture, which is problematic for fastidious slow-growing bacteria such as Mycobacterium avium subsp. paratuberculosis, where it can take up to 4 months to confirm growth. This study aimed to identify an assay that can rapidly quantify the number of viable M. avium subsp. paratuberculosis cells in a cellular sample. Three commercially available bacterial viability assays along with a modified liquid culture method coupled with high-throughput quantitative PCR growth detection were assessed. Criteria for assessment included the ability of each assay to differentiate live and dead M. avium subsp. paratuberculosis organisms and their accuracy at low bacterial concentrations. Using the culture-based method, M. avium subsp. paratuberculosis growth was reliably detected and quantified within 2 weeks. There was a strong linear association between the 2-week growth rate and the initial inoculum concentration. The number of viable M. avium subsp. paratuberculosis cells in an unknown sample was quantified based on the growth rate, by using growth standards. In contrast, none of the commercially available viability assays were suitable for use with samples from in vitro cellular infection assays. IMPORTANCE Rapid quantification of the viability of Mycobacterium avium subsp. paratuberculosis in samples from in vitro cellular infection assays is important, as it allows these assays to be carried out on a large scale. In vitro cellular infection assays can function as a preliminary screening tool, for vaccine development or antimicrobial screening, and also to extend findings derived from experimental animal trials. Currently, by using culture, it takes up to 4 months to obtain quantifiable results regarding M. avium subsp. paratuberculosis viability after an in vitro infection assay; however, with the quantitative PCR and liquid culture method

  6. Horizontal model fusion paradigm

    NASA Astrophysics Data System (ADS)

    Julier, Simon J.; Durrant-Whyte, Hugh F.

    1996-05-01

    In navigation and tracking problems, the identification of an appropriate model of vehicular or target motion is vital to most practical data fusion algorithms. The true system dynamics are rarely known, and approximations are usually employed. Since systems can exhibit strikingly different behaviors, multiple models may be needed to describe each of these behaviors. Current methods either use model switching (a single process model is chosen from the set using a decision rule) or consider the models as a set of competing hypothesis, only one of which is 'correct'. However, these methods fail to exploit the fact that all models are of the same system and that all of them are, to some degree, 'correct'. In this paper we present a new paradigm for fusing information from a set of multiple process models. The predictions from each process model are regarded as observations which are corrupted by correlated noise. By employing the standard Kalman filter equations we combine data from multiple sensors and multiple process models optimally. There are a number of significant practical advantages to this technique. First, the performance of the system always equals or betters that of the best estimator in the set of models being used. Second, the same decision theoretic machinery can be used to select the process models as well as the sensor suites.

  7. Novel Single Nucleotide Polymorphism-Based Assay for Genotyping Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Goldstone, Robert J.; McLuckie, Joyce; Smith, David G. E.

    2015-01-01

    Typing of Mycobacterium avium subspecies paratuberculosis strains presents a challenge, since they are genetically monomorphic and traditional molecular techniques have limited discriminatory power. The recent advances and availability of whole-genome sequencing have extended possibilities for the characterization of Mycobacterium avium subspecies paratuberculosis, and whole-genome sequencing can provide a phylogenetic context to facilitate global epidemiology studies. In this study, we developed a single nucleotide polymorphism (SNP) assay based on PCR and restriction enzyme digestion or sequencing of the amplified product. The SNP analysis was performed using genome sequence data from 133 Mycobacterium avium subspecies paratuberculosis isolates with different genotypes from 8 different host species and 17 distinct geographic regions around the world. A total of 28,402 SNPs were identified among all of the isolates. The minimum number of SNPs required to distinguish between all of the 133 genomes was 93 and between only the type C isolates was 41. To reduce the number of SNPs and PCRs required, we adopted an approach based on sequential detection of SNPs and a decision tree. By the analysis of 14 SNPs Mycobacterium avium subspecies paratuberculosis isolates can be characterized within 14 phylogenetic groups with a higher discriminatory power than mycobacterial interspersed repetitive unit–variable number tandem repeat assay and other typing methods. Continuous updating of genome sequences is needed in order to better characterize new phylogenetic groups and SNP profiles. The novel SNP assay is a discriminative, simple, reproducible method and requires only basic laboratory equipment for the large-scale global typing of Mycobacterium avium subspecies paratuberculosis isolates. PMID:26677250

  8. A new paradigm (Westphal-Paradigm) to study the neural correlates of panic disorder with agoraphobia.

    PubMed

    Wittmann, A; Schlagenhauf, F; John, T; Guhn, A; Rehbein, H; Siegmund, A; Stoy, M; Held, D; Schulz, I; Fehm, L; Fydrich, T; Heinz, A; Bruhn, H; Ströhle, A

    2011-04-01

    Agoraphobia (with and without panic disorder) is a highly prevalent and disabling anxiety disorder. Its neural complexity can be characterized by specific cues in fMRI studies. Therefore, we developed a fMRI paradigm with agoraphobia-specific stimuli. Pictures of potential agoraphobic situations were generated. Twenty-six patients, suffering from panic disorder and agoraphobia, and 22 healthy controls rated the pictures with respect to arousal, valence, and agoraphobia-related anxiety. The 96 pictures, which discriminated best between groups were chosen, split into two parallel sets and supplemented with matched neutral pictures from the International Affective Picture System. Reliability, criterion, and construct validity of the picture set were determined in a second sample (44 patients, 28 controls). The resulting event-related "Westphal-Paradigm" with cued and uncued pictures was tested in a fMRI pilot study with 16 patients. Internal consistency of the sets was very high; parallelism was given. Positive correlations of picture ratings with Mobility Inventory and Hamilton anxiety scores support construct validity. FMRI data revealed activations in areas associated with the fear circuit including amygdala, insula, and hippocampal areas. Psychometric properties of the Westphal-Paradigm meet necessary quality requirements for further scientific use. The paradigm reliably produces behavioral and fMRI patterns in response to agoraphobia-specific stimuli. To our knowledge, it is the first fMRI paradigm with these properties. This paradigm can be used to further characterize the functional neuroanatomy of panic disorder and agoraphobia and might be useful to contribute data to the differentiation of panic disorder and agoraphobia as related, but conceptually different clinical disorders.

  9. Osteopontin Immunoreactivity in the Ileum and Ileoceccal Lymph Node of Dairy Cows Naturally Infected with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Osteopontin (Opn), a highly acidic glycoprotein, promotes cellular adhesion and recruitment and has been shown to be upregulated in the granulomas of mycobacterial infections. Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is associated with granulomatous enteritis. ...

  10. Faecal bacterial composition in dairy cows shedding Mycobacterium avium subsp. paratuberculosis in faeces in comparison with nonshedding cows.

    PubMed

    Kaevska, Marija; Videnska, Petra; Sedlar, Karel; Bartejsova, Iva; Kralova, Alena; Slana, Iva

    2016-06-01

    The aim of this study was to determine possible differences in the faecal microbiota of dairy cows infected with Mycobacterium avium subsp. paratuberculosis (Johne's disease) in comparison with noninfected cows from the same herds. Faecal samples from cows in 4 herds were tested for M. avium subsp. paratuberculosis by real-time PCR, and faecal bacterial populations were analysed by 454 pyrosequencing of the 16S rRNA gene. The most notable differences between shedding and nonshedding cows were an increase in the genus Psychrobacter and a decrease in the genera Oscillospira, Ruminococcus, and Bifidobacterium in cows infected with M. avium subsp. paratuberculosis. The present study is the first to report the faecal microbial composition in dairy cows infected with M. avium subsp. paratuberculosis.

  11. Osteopontin: A Novel Cytokine Involved in the Regulation of Mycobacterium avium subsp. paratuberculosis Infection in Periparturient Dairy Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Osteopontin (Opn), an important mediator of the cell-mediated immune response, enhances the host immune response against mycobacterial infections. Infections caused by the intracellular bacterium, Mycobacterium avium subsp. paratuberculosis (MAP), have a devastating impact on the dairy industry. ...

  12. Immune-Enhancing Effects of Taishan Pinus massoniana Pollen Polysaccharides on DNA Vaccine Expressing Bordetella avium ompA

    PubMed Central

    Zhu, Fujie; Liu, Xiao; Sun, Zhenhong; Yu, Cuilian; Liu, Liping; Yang, Shifa; Li, Bing; Wei, Kai; Zhu, Ruiliang

    2016-01-01

    Bordetella avium is the causative agent of bordetellosis, which remains to be the cause of severe losses in the turkey industry. Given the lack of vaccines that can provide good protection, developing a novel vaccine against B. avium infection is crucial. In this study, we constructed a eukaryotic expression plasmid, which expressed the outer membrane protein A (ompA) of B. avium, to prepare a B. avium recombinant ompA-DNA vaccine. Three concentrations (low, middle, and high) of Taishan Pinus massoniana pollen polysaccharides (TPPPS), a known immunomodulator, were used as adjuvants, and their immune conditioning effects on the developed DNA vaccine were examined. The pure ompA-DNA vaccine, Freund’s incomplete adjuvant ompA-DNA vaccine, and the empty plasmid served as the controls. The chickens in each group were separately inoculated with these vaccines three times at 1, 7, and 14 days old. Dynamic changes in antibody production, cytokine secretion, and lymphocyte count were then determined from 7 to 49 days after the first inoculation. Protective rates of the vaccines were also determined after the third inoculation. Results showed that the pure DNA vaccine obviously induced the production of antibodies, the secretion of cytokines, and the increase in CD4+ and CD8+ T lymphocyte counts in peripheral blood, as well as provided a protective rate of 50% to the B. avium-challenged chickens. The chickens inoculated with the TPPPS adjuvant ompA-DNA vaccine and Freund’s adjuvant ompA-DNA vaccine demonstrated higher levels of immune responses than those inoculated with pure ompA-DNA vaccine, whereas only the ompA-DNA vaccine with 200 mg/mL TPPPS completely protected the chickens against B. avium infection. These findings indicate that the B. avium ompA-DNA vaccine combined with TPPPS is a potentially effective B. avium vaccine. PMID:26870023

  13. Contrasting results of culture-dependent and molecular analyses of Mycobacterium avium subsp. paratuberculosis from wood bison.

    PubMed

    Forde, Taya; De Buck, Jeroen; Elkin, Brett; Kutz, Susan; van der Meer, Frank; Orsel, Karin

    2013-07-01

    Reduced to near extinction in the late 1800s, a number of wood bison populations (Bison bison athabascae) have been re-established through reintroduction initiatives. Although an invaluable tool for conservation, translocation of animals can spread infectious agents to new areas or expose animals to pathogens in their new environment. Mycobacterium avium subsp. paratuberculosis, a bacterium that causes chronic enteritis in ruminants, is among the pathogens of potential concern for wood bison management and conservation. In order to inform translocation decisions, our objectives were to determine the M. avium subsp. paratuberculosis infection status of wood bison herds in Canada and to culture and genetically characterize the infective strain(s). We tested fecal samples from bison (n = 267) in nine herds using direct PCR for three M. avium subsp. paratuberculosis-specific genetic targets with different copy numbers within the M. avium subsp. paratuberculosis genome. Restriction enzyme analysis (REA) and sequencing of IS1311 were performed on seven samples from five different herds. We also evaluated a panel of different culture conditions for their ability to support M. avium subsp. paratuberculosis growth from feces and tissues of direct-PCR-positive animals. Eighty-one fecal samples (30%) tested positive using direct IS900 PCR, with positive samples from all nine herds; of these, 75% and 21% were also positive using ISMAP02 and F57, respectively. None of the culture conditions supported the growth of M. avium subsp. paratuberculosis from PCR-positive samples. IS1311 REA and sequencing indicate that at least two different M. avium subsp. paratuberculosis strain types exist in Canadian wood bison. The presence of different M. avium subsp. paratuberculosis strains among wood bison herds should be considered in the planning of translocations.

  14. Virulence and immunity orchestrated by the global gene regulator sigL in Mycobacterium avium subsp. paratuberculosis.

    PubMed

    Ghosh, Pallab; Steinberg, Howard; Talaat, Adel M

    2014-07-01

    Mycobacterium avium subsp. paratuberculosis causes Johne's disease in ruminants, a chronic enteric disease responsible for severe economic losses in the dairy industry. Global gene regulators, including sigma factors are important in regulating mycobacterial virulence. However, the biological significance of such regulators in M. avium subsp. paratuberculosis rremains elusive. To better decipher the role of sigma factors in M. avium subsp. paratuberculosis pathogenesis, we targeted a key sigma factor gene, sigL, activated in mycobacterium-infected macrophages. We interrogated an M. avium subsp. paratuberculosis ΔsigL mutant against a selected list of stressors that mimic the host microenvironments. Our data showed that sigL was important in maintaining bacterial survival under such stress conditions. Survival levels further reflected the inability of the ΔsigL mutant to persist inside the macrophage microenvironments. Additionally, mouse infection studies suggested a substantial role for sigL in M. avium subsp. paratuberculosis virulence, as indicated by the significant attenuation of the ΔsigL-deficient mutant compared to the parental strain. More importantly, when the sigL mutant was tested for its vaccine potential, protective immunity was generated in a vaccine/challenge model of murine paratuberculosis. Overall, our study highlights critical role of sigL in the pathogenesis and immunity of M. avium subsp. paratuberculosis infection, a potential role that could be shared by similar proteins in other intracellular pathogens.

  15. Toll-like receptor 6 senses Mycobacterium avium and is required for efficient control of mycobacterial infection.

    PubMed

    Marinho, Fábio A V; de Paula, Rafaella R; Mendes, Aline C; de Almeida, Leonardo A; Gomes, Marco T R; Carvalho, Natália B; Oliveira, Fernanda S; Caliari, Marcelo V; Oliveira, Sergio C

    2013-09-01

    Mycobacterium avium has been reported to signal through both Toll-like receptor (TLR2) and TLR9. To investigate the role of TLR6 in innate immune responses to M. avium, TLR6, MyD88, TLR2, and TLR2/6 KO mice were infected with this pathogen. Bacterial burdens were higher in the lungs and livers of infected TLR6, TLR2, TLR2/6, and MyD88 KO mice compared with those in C57BL/6 mice, which indicates that TLR6 is required for the efficient control of M. avium infection. However, TLR6 KO spleen cells presented with normal M. avium induced IFN-γ responses as measured by ELISA and flow cytometry. In contrast, the production of IFN-γ in lung tissue was diminished in all studied KO mice. Furthermore, only MyD88 deficiency reduced granuloma areas in mouse livers. Moreover, we determined that TLR6 plays an important role in controlling bacterial growth within macrophages and in the production of TNF-α, IL-12, and IL-6 by M. avium infected DCs. Finally, the lack of TLR6 reduced activation of MAPKs and NF-κB in DCs. In summary, TLR6 is required for full resistance to M. avium and for the activation of DCs to produce proinflammatory cytokines.

  16. Reclassification of Pasteurella gallinarum, [Haemophilus] paragallinarum, Pasteurella avium and Pasteurella volantium as Avibacterium gallinarum gen. nov., comb. nov., Avibacterium paragallinarum comb. nov., Avibacterium avium comb. nov. and Avibacterium volantium comb. nov.

    PubMed

    Blackall, Patrick J; Christensen, Henrik; Beckenham, Tim; Blackall, Linda L; Bisgaard, Magne

    2005-01-01

    This paper describes a phenotypic and genotypic investigation of the taxonomy of [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium, a major subcluster within the avian 16S rRNA cluster 18 of the family Pasteurellaceae. An extended phenotypic characterization was performed of the type strain of [Haemophilus] paragallinarum, which is NAD-dependent, and eight NAD-independent strains of [Haemophilus] paragallinarum. Complete 16S rRNA gene sequences were obtained for one NAD-independent and four NAD-dependent [Haemophilus] paragallinarum strains. These five sequences along with existing 16S rRNA gene sequences for 11 other taxa within avian 16S rRNA cluster 18 as well as seven other taxa from the Pasteurellaceae were subjected to phylogenetic analysis. The analysis demonstrated that [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium formed a monophyletic group with a minimum of 96.8 % sequence similarity. This group can also be separated by phenotypic testing from all other recognized and named taxa within the Pasteurellaceae. As both genotypic and phenotypic testing support the separate and distinct nature of this subcluster, the transfer is proposed of Pasteurella gallinarum, [Haemophilus] paragallinarum, Pasteurella avium and Pasteurella volantium to a new genus Avibacterium as Avibacterium gallinarum gen. nov., comb. nov., Avibacterium paragallinarum comb. nov., Avibacterium avium comb. nov. and Avibacterium volantium comb. nov. The type strains are NCTC 1118T (Avibacterium gallinarum), NCTC 11296T (Avibacterium paragallinarum), NCTC 11297T (Avibacterium avium) and NCTC 3438T (Avibacterium volantium). Key characteristics that separate these four species are catalase activity (absent only in Avibacterium paragallinarum) and production of acid from galactose (negative only in Avibacterium paragallinarum), maltose (negative only in Avibacterium avium) and mannitol (negative

  17. Health Inequities: Evaluation of Two Paradigms

    ERIC Educational Resources Information Center

    Ashcroft, Rachelle

    2010-01-01

    Social work practice in health is shaped by underlying paradigms. To effectively target health inequities, practitioners need to consider appropriate paradigms. In this exploration of how six health paradigms shape theory and practice, the two health paradigms that most attended to health inequalities are social determinants of health and…

  18. Induction of in vivo resistance to Mycobacterium avium infection by intramuscular injection with DNA encoding interleukin-18

    PubMed Central

    Kim, S H; Cho, D; Kim, T S

    2001-01-01

    Interferon-gamma (IFN-γ) is closely associated with the generation of cell-mediated immunity and resistance to intracellular parasites. Interleukin-18 (IL-18) was known to strongly induce IFN-γ production by T cells and natural killer (NK) cells. In order to determine whether injection with DNA encoding IL-18 can stimulate the resistance to Mycobacterium avium complex (MAC) infection, the mature IL-18 cDNA with κ leader sequence was cloned under control of the cytomegalovirus (CMV) promoter (TcCMVIL-18) and its effect on MAC infection was investigated in genetically susceptible BALB/c mice. Injection with the TcCMVIL-18 DNA during intranasal infection with MAC resulted in a significant decrease in bacterial load of lung during the entire 8-week observation period, while injection with the TcCMV control DNA did not. Lung cells in mice injected with the TcCMVIL-18 DNA showed persistent production of IFN-γ throughout the 8-week period. Furthermore, immunization with the TcCMVIL-18 DNA induced and maintained significantly higher levels of cytotoxic activity and nitric oxide production by lung cells than immunization with the TcCMV control vector. This work suggests that IL-18 DNA vaccination may be useful in the immunotherapeutic or immunoprotection approaches of infections by intracellular parasites such as mycobacteria. PMID:11260329

  19. Dose-dependent interferon-gamma release in dairy calves experimentally infected with Mycobacterium avium subspecies paratuberculosis.

    PubMed

    Mortier, Rienske A R; Barkema, Herman W; Wilson, Todd A; Sajobi, Tolulope T; Wolf, Robert; De Buck, Jeroen

    2014-10-15

    The interferon-gamma (IFN-γ) release assay is considered useful for diagnosis of subclinical paratuberculosis. However, interpretation can be subjective and complex; therefore, additional information regarding the course of the cellular immune response and effects of age and dose at infection would be helpful. Thirty-three calves were randomly allocated to 10 challenge groups and a negative control group. Calves were inoculated orally at 2 weeks or at 3, 6, 9, or 12 months of age. Within each age group, calves received either a high or low dose of Mycobacterium avium subspecies paratuberculosis (MAP). Monthly blood samples were collected, stimulated with Purified Protein Derivative (PPD) Johnin in vitro, and the subsequent release of IFN-γ measured. Calves inoculated with a high dose had earlier and stronger IFN-γ responses than low-dose calves. Furthermore, calves inoculated at 2 weeks of age produced less IFN-γ compared to those inoculated later in life. The IFN-γ response peaked (on average) 4 months after exposure; therefore, this would be an optimal interval to test cattle for MAP-infection (although the timing of field-based infections is unknown and clearance of infection a possibility). To conclude, the IFN-γ release assay could be a valuable diagnostic test on herd-level to indicate exposure to MAP.

  20. Mycobacterium avium ssp. paratuberculosis recombinant heat shock protein 70 interaction with different bovine antigen-presenting cells.

    PubMed

    Langelaar, M F M; Hope, J C; Rutten, V P M G; Noordhuizen, J P T M; van Eden, W; Koets, A P

    2005-03-01

    Abstract Heat shock proteins (Hsp) can deliver antigen into the major histocompatibility complex class I presentation pathway of antigen-presenting cells (APC), a process called cross priming, thus stimulating antigen-specific CD8+ T-cell reactions. Hsp were shown to elicit proinflammatory responses in APC. Both processes require interaction of Hsp with APC via specific receptors. This study describes the interaction of recombinant Hsp70 (rHsp70) of Mycobacterium avium subspecies paratuberculosis with bovine peripheral blood mononuclear cells that was restricted to CD14+ cells. Characterized monocyte-derived macrophages, monocyte-derived dendritic cells (DC) and BoMac, an immortalized bovine macrophage cell line, were used to investigate the interaction of rHsp70 with different bovine APC. Saturation of immature DC with high concentrations of rHsp70 is demonstrated, and it was found that interaction of rHsp70 with DC was related to the maturation stage of the DC. Involvement of CD91 as a cellular receptor for rHsp70 was demonstrated; however, competition studies with immature DC demonstrated that other receptors exist on bovine APC. These data suggest that rHsp70-based vaccines may be useful for the successful immunization of cattle.

  1. Paradigms of Sulfotransferase Catalysis

    PubMed Central

    Wang, Ting; Cook, Ian; Falany, Charles N.; Leyh, Thomas S.

    2014-01-01

    Human cytosolic sulfotransferases (SULTs) regulate the activities of thousands of signaling small molecules via transfer of the sulfuryl moiety (-SO3) from 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to the hydroxyls and primary amines of acceptors. Sulfonation controls the affinities of ligands for their targets, and thereby regulates numerous receptors, which, in turn, regulate complex cellular responses. Despite their biological and medical relevance, basic SULT mechanism issues remain unresolved. To settle these issues, and to create an in-depth model of SULT catalysis, the complete kinetic mechanism of a representative member of the human SULT family, SULT2A1, was determined. The mechanism is composed of eight enzyme forms that interconvert via 22 rate constants, each of which was determined independently. The result is a complete quantitative description of the mechanism that accurately predicts complex enzymatic behavior. This is the first description of a SULT mechanism at this resolution, and it reveals numerous principles of SULT catalysis and resolves previously ambiguous issues. The structures and catalytic behaviors SULTs are highly conserved; hence, the mechanism presented here should prove paradigmatic for the family. PMID:25056952

  2. Variable-Number Tandem-Repeat Analysis of Respiratory and Household Water Biofilm Isolates of “Mycobacterium avium subsp. hominissuis” with Establishment of a PCR Database

    PubMed Central

    Iakhiaeva, Elena; Howard, Susan T.; Brown Elliott, Barbara A.; McNulty, Steven; Newman, Kristopher L.; Falkinham, Joseph O.; Williams, Myra; Kwait, Rebecca; Lande, Leah; Vasireddy, Ravikiran; Turenne, Christine

    2016-01-01

    “Mycobacterium avium subsp. hominissuis” is an important cause of pulmonary disease. It is acquired from environmental sources, but there is no methodology for large population studies. We evaluated the potential of variable-number tandem-repeat (VNTR) analysis. Clinical and household biofilm M. avium isolates underwent molecular identification. Testing for IS901 was done to separate M. avium subsp. avium from M. avium subsp. hominissuis. VNTR types were defined using VNTR loci, and subtyping was performed using 3′ hsp65 and internal transcribed spacer (ITS) sequencing. Forty-nine VNTR types and eight subtypes of M. avium subsp. hominissuis (IS901 negative) were identified among 416 isolates of M. avium from 121 patients and 80 biofilm sites. Of those types, 67% were found only among patient isolates, 11% only among household water isolates, and 23% among both. Of 13 VNTR types that included ≥4 patients, the majority (61.5%) represented geographic clustering (same city). Most VNTR types with multiple patients belonged to the same 3′ hsp65 sequence code (sequevar). A total of 44 isolates belonging to four M. avium subsp. hominissuis VNTR types (8%), including three with the rare Mav-F ITS sequence and 0/8 subspecies, produced amplicons with IS901 PCR primers. By sequencing, all 44 amplicons were not IS901 but ISMav6, which was recently observed in Japan but had not been previously described among U.S. isolates. VNTR analysis of M. avium subsp. hominissuis isolates is easier and faster than pulsed-field gel electrophoresis. Seven VNTR loci separated 417 isolates into 49 types. No isolates of M. avium subsp. avium were identified. The distributions of the VNTR copy numbers, the allelic diversity, and the low prevalence of ISMav6 differed from the findings for respiratory isolates reported from Japan. PMID:26739155

  3. Disseminated mycobacteriosis manifesting as paraplegia in two Parma wallabies (Macropus parma) naturally exposed to Mycobacterium avium.

    PubMed

    Robveille, Cynthia; Albaric, Olivier; Gaide, Nicolas; Abadie, Jérome

    2015-11-01

    Two captive female Parma wallabies (Macropus parma) died after a history of flaccid paraplegia. On postmortem examination, granulomatous and suppurative osteomyelitis involving the left ischium and the lumbosacral region, with meningeal extension at the cauda equina, and caseonecrotic mastitis were the most significant changes. Multiple small nodules in the liver and spleen, and an enlargement of some lymph nodes with central caseous necrosis were also observed. Microscopically, a disseminated granulomatous inflammation with numerous multinucleate giant cells was seen. Numerous acid-fast bacilli were detected in macrophages, in multinucleated giant cells, and free in the central necrosis and suppurative exudate. After culture, polymerase chain reaction assays were carried out to detect the 65-kDa heat shock protein (Hsp65) and insertion sequences (IS)1245 and IS900. The causative agent was identified as Mycobacterium avium subsp. avium.

  4. Disseminated Mycobacterium avium subsp. paratuberculosis infection in two wild Eurasian otters (Lutra lutra L.) from Portugal.

    PubMed

    Matos, Ana Cristina; Figueira, Luis; Martins, Maria Helena; Matos, Manuela; Alvares, Sofia; Pinto, Maria Lurdes; Coelho, Ana Cláudia

    2013-03-01

    Disseminated Mycobacterium avium subsp. paratuberculosis (MAP) infections were found in two Eurasian otters (Lutra lutra, L. 1758) killed by vehicular trauma in February and March 2010 in Castelo Branco, Portugal. At postmortem examination, the organs showed no significant gross alterations; however, microscopically, both animals had diffuse lymphadenitis with macrophage infiltration and deposition of hyaline material in the center of the lymphoid follicles. Acid-fast organisms were isolated from gastrointestinal tissue samples via bacteriologic culture. These organisms were identified as M. avium subsp. paratuberculosis by IS900 polymerase chain reaction (PCR). Additionally, direct IS900 PCR-positive results were obtained for multiple organs of both animals. This is the first report of MAP infection of otters in Portugal.

  5. Lactase persistence, NOD2 status and Mycobacterium avium subsp. paratuberculosis infection associations to Inflammatory Bowel Disease

    PubMed Central

    2012-01-01

    Background Inflammatory Bowel Disease (IBD), which includes both Crohn’s disease (CD) and ulcerative colitis (UC), is caused by a complex interplay involving genetic predisposition, environmental factors and an infectious agent. Mycobacterium avium subsp. paratuberculosis (MAP) is a promising pathogen candidate since it produces a chronic intestinal inflammatory disease in ruminants that resembles CD in humans. MAP is a ubiquitous microorganism, although its presence in the food chain, especially in milk from infected animals, is what made us think that there could be an association between lactase persistence (LP) and IBD. The LCT mutation has brought adaptation to dairy farming which in turn would have increased exposure of the population to infection by MAP. NOD2 gene mutations are highly associated to CD. Methods In our study, CD and UC patients and controls from the North of Spain were genotyped for the lactase gene (LCT) and for three NOD-2 variants, R702W, G908R and Cins1007fs. MAP PCR was carried out in order to assess MAP infection status and these results were correlated with LCT and NOD2 genotypes. Results As for LP, no association was found with IBD, although UC patients were less likely to present the T/T−13910 variant compared to controls, showing a higher C-allele frequency and a tendency to lactase non-persistence (LNP). NOD2 mutations were associated to CD being the per-allele risk higher for the Cins1007fs variant. MAP infection was more extended among the healthy controls (45.2%) compared to CD patients (21.38%) and UC patients (19.04%) and this was attributed to therapy. The Asturian CD cohort presented higher levels of MAP prevalence (38.6%) compared to the Basque CD cohort (15.5%), differences also attributed to therapy. No interaction was found between MAP infection and LCT or NOD2 status. Conclusions We conclude that LP is not significantly associated with IBD, but that MAP infection and NOD2 do show not mutually interacting associations

  6. Iron-sparing Response of Mycobacterium avium subsp. paratuberculosis is strain dependent

    PubMed Central

    2010-01-01

    Background Two genotypically and microbiologically distinct strains of Mycobacterium avium subsp. paratuberculosis (MAP) exist - S and C MAP strains that primarily infect sheep and cattle, respectively. Concentration of iron in the cultivation medium has been suggested as one contributing factor for the observed microbiologic differences. We recently demonstrated that S strains have defective iron storage systems, leading us to propose that these strains might experience iron toxicity when excess iron is provided in the medium. To test this hypothesis, we carried out transcriptional and proteomic profiling of these MAP strains under iron-replete or -deplete conditions. Results We first complemented M. smegmatisΔideR with IdeR of C MAP or that derived from S MAP and compared their transcription profiles using M. smegmatis mc2155 microarrays. In the presence of iron, sIdeR repressed expression of bfrA and MAP2073c, a ferritin domain containing protein suggesting that transcriptional control of iron storage may be defective in S strain. We next performed transcriptional and proteomic profiling of the two strain types of MAP under iron-deplete and -replete conditions. Under iron-replete conditions, C strain upregulated iron storage (BfrA), virulence associated (Esx-5 and antigen85 complex), and ribosomal proteins. In striking contrast, S strain downregulated these proteins under iron-replete conditions. iTRAQ (isobaric tag for relative and absolute quantitation) based protein quantitation resulted in the identification of four unannotated proteins. Two of these were upregulated by a C MAP strain in response to iron supplementation. The iron-sparing response to iron limitation was unique to the C strain as evidenced by repression of non-essential iron utilization enzymes (aconitase and succinate dehydrogenase) and upregulation of proteins of essential function (iron transport, [Fe-S] cluster biogenesis and cell division). Conclusions Taken together, our study revealed

  7. Effective heat inactivation of Mycobacterium avium subsp. paratuberculosis in raw milk contaminated with naturally infected feces.

    PubMed

    Rademaker, Jan L W; Vissers, Marc M M; Te Giffel, Meike C

    2007-07-01

    The effectiveness of high-temperature, short holding time (HTST) pasteurization and homogenization with respect to inactivation of Mycobacterium avium subsp. paratuberculosis was evaluated quantitatively. This allowed a detailed determination of inactivation kinetics. High concentrations of feces from cows with clinical symptoms of Johne's disease were used to contaminate raw milk in order to realistically mimic possible incidents most closely. Final M. avium subsp. paratuberculosis concentrations varying from 10(2) to 3.5 x 10(5) cells per ml raw milk were used. Heat treatments including industrial HTST were simulated on a pilot scale with 22 different time-temperature combinations, including 60 to 90 degrees C at holding (mean residence) times of 6 to 15 s. Following 72 degrees C and a holding time of 6 s, 70 degrees C for 10 and 15 s, or under more stringent conditions, no viable M. avium subsp. paratuberculosis cells were recovered, resulting in >4.2- to >7.1-fold reductions, depending on the original inoculum concentrations. Inactivation kinetic modeling of 69 quantitative data points yielded an E(a) of 305,635 J/mol and an lnk(0) of 107.2, corresponding to a D value of 1.2 s at 72 degrees C and a Z value of 7.7 degrees C. Homogenization did not significantly affect the inactivation. The conclusion can be drawn that HTST pasteurization conditions equal to 15 s at > or =72 degrees C result in a more-than-sevenfold reduction of M. avium subsp. paratuberculosis.

  8. Isolation of flavonoids from the heartwood and resin of Prunus avium and some preliminary biological investigations.

    PubMed

    McNulty, James; Nair, Jerald J; Bollareddy, Endreddy; Keskar, Kunal; Thorat, Amol; Crankshaw, Denis J; Holloway, Alison C; Khan, Ghaznia; Wright, Gerard D; Ejim, Linda

    2009-12-01

    An investigation of the constituents in heartwood and resin of Prunus avium is reported. A mini-library of structurally diverse flavanones and flavones was screened for human cytochrome P450 1A1, 3A4 and 19 (aromatase) inhibition, and for antifungal activity against a panel of pathogenic fungi. The defensive role of these natural plant flavonoids as antifungal phytoalexins and phytoanticipins is discussed.

  9. Survival and Dormancy of Mycobacterium avium subsp. paratuberculosis in the Environment

    PubMed Central

    Whittington, Richard J.; Marshall, D. Jeff; Nicholls, Paul J.; Marsh, Ian B.; Reddacliff, Leslie A.

    2004-01-01

    The survival of Mycobacterium avium subsp. paratuberculosis was studied by culture of fecal material sampled at intervals for up to 117 weeks from soil and grass in pasture plots and boxes. Survival for up to 55 weeks was observed in a dry fully shaded environment, with much shorter survival times in unshaded locations. Moisture and application of lime to soil did not affect survival. UV radiation was an unlikely factor, but infrared wavelengths leading to diurnal temperature flux may be the significant detrimental component that is correlated with lack of shade. The organism survived for up to 24 weeks on grass that germinated through infected fecal material applied to the soil surface in completely shaded boxes and for up to 9 weeks on grass in 70% shade. The observed patterns of recovery in three of four experiments and changes in viable counts were indicative of dormancy, a hitherto unreported property of this taxon. A dps-like genetic element and relA, which are involved in dormancy responses in other mycobacteria, are present in the M. avium subsp. paratuberculosis genome sequence, providing indirect evidence for the existence of physiological mechanisms enabling dormancy. However, survival of M. avium subsp. paratuberculosis in the environment is finite, consistent with its taxonomic description as an obligate parasite of animals. PMID:15128561

  10. Radioprotection of Swiss albino mice by Prunus avium with special reference to hematopoietic system.

    PubMed

    Sisodia, Rashmi; Singh, Smita; Mundotiya, Chaturbhuj; Meghnani, Ekta; Srivastava, Preeti

    2011-01-01

    Prunus avium (family Rosaceae) has been used ethnomedicinally for the treatment of many diseases,but its radioprotective efficacy has hardly been explored. Presence of high anthocyanin content and phenolic compound with good antioxidative capacity has been reported by researchers. Its radioprotective effect against 5, 7, 10, and 12 Gygamma radiation was evaluated by 30 day survival assay. Regression analysis yielded LD(50/30) 5.81 and 9.43Gy for irradiated only and (P. avium fruit extract) PAE + radiation groups, respectively. The dose reduction factor was computed as 1.62. For biochemical and hematological studies, Swiss albino mice were divided into four groups: (i) control (vehicle treated), (ii) PAE treated (450 mg kg/day for 15 consequetive days), (iii) irradiated (5 Gy), and (4) PAE + irradiated. The irradiation of animals resulted in a significant elevation of lipid peroxidation and depletion in glutathione and protein levels in blood serum and spleen, which could be significantly checked by administration of PAE. Radiation-induced deficit in blood sugar, cholesterol, and hematological constituents could also be modulated by supplementation of PAE before and after irradiation. The possible prophylactic and therapeutic action noted by P. avium against radiation induced metabolic disorders may be due to synergistic action of various antioxidants, minerals, vitamins, etc., present in the fruit. Further mechanistic studies aimed at identifying the role of major ingredients in the extract are needed.

  11. Genetic relationships between diploid and allotetraploid cherry species (Prunus avium, Prunus x gondouinii and Prunus cerasus).

    PubMed

    Tavaud, M; Zanetto, A; David, J L; Laigret, F; Dirlewanger, E

    2004-12-01

    Prunus avium L. (diploid, AA, 2n=2x=16), Prunus cerasus L. (allotetraploid, AAFF, 2n=4x=32) species, and their hybrid Prunus x gondouinii Rehd., constitute the most widely cultivated cherry tree species. P. cerasus is supposed to be an hybrid species produced by the union of unreduced P. avium gametes and normal P. fruticosa gametes. A continuum of morphological traits between these three species makes their assignation difficult. The aim of this paper is to study the genetic relationships between tetraploid and diploid cherry species. In all, 114 genotypes belonging to these species were analyzed using 75 AFLP markers. The coordinates of these genotypes on the first axis of a correspondence analysis allowed us to clearly distinguish each species, to identify misclassifications and to assign unknown genotypes to one species. We showed that there are specific alleles in P. cerasus, which are not present in the A genome of P. avium and which probably come from the F genome of P. cerasus. The frequencies of each marker in the A and the F genomes were estimated in order to identify A and F specific markers. We discuss the utility of these specific markers for finding the origin of the A and F genomes in the allopolyploid species.

  12. Acute toxicity effects of Prunus avium fruit extract and selection of optimum dose against radiation exposure.

    PubMed

    Sisodia, Rashmi; Sharma, K; Singh, Smita

    2009-01-01

    The objective of the study was to evaluate the acute toxicity of different doses of the methanolic extract of the fruit pulp of Prunus avium (family Rosaceae), which is used ethno-medicinally for the treatment of various diseases, and to find out the optimal dose of Prunus avium extract against 10 Gy gamma-radiation exposure. To test acute toxicity in mice, different doses of PAE (Prunus avium fruit extract) were given orally for 15 consecutive days, after which the animals were observed for another 15 days; the LD50/15 of the methanolic extract was calculated to be 4.947 gm/kg body weight (b.wt). In optimum dose selection against radiation exposure, oral administration of 450 mg/kg b.wt/d of PAE for 15 consecutive days before exposure to 10 Gy of gamma-radiation was found to afford maximum protection in terms of body weight and survivability of the mice in comparison to other doses.

  13. Prunus avium: nuclear DNA study in wild populations and sweet cherry cultivars.

    PubMed

    Guarino, Carmine; Santoro, Simona; De Simone, Luciana; Cipriani, Guido

    2009-04-01

    The PCR-SSR technique was used to detect nuclear DNA diversity in five wild populations of Prunus avium from deciduous forests in Italy, Slovenia, and Croatia and 87 sweet cherry accessions from different geographical areas that have been maintained in the sweet cherry collection in Italy. This sweet cherry collection includes local accessions from the Campania Region as well as accessions from different countries. Twenty-eight microsatellites, previously developed in this species, generated polymorphic amplification products. Between 2 and 14 alleles were revealed for the polymorphic loci studied, with the expected heterozygosity ranging from 0.045 to 0.831. The total probability of identity was 56.94 x 10-18. A model-based Bayesian clustering analysis identified nine distinct gene pools in cultivated P. avium. The probability that wild populations were assigned to cultivated gene pools indicated that three gene pools accounted for the genomic origin of 53% of P. avium sampled. A dendrogram was generated using UPGMA (unweighted pair group method with arithmetic averages) based on Nei genetic distance analysis. This dendrogram classified most of the genotypes into one major group with an additional group of five accessions. The results indicate that this set of SSRs is highly informative, and they are discussed in terms of the implications for sweet cherry characterization.

  14. Paradigm Shifts in Ophthalmic Diagnostics*

    PubMed Central

    Sebag, J.; Sadun, Alfredo A.; Pierce, Eric A.

    2016-01-01

    Purpose Future advances in ophthalmology will see a paradigm shift in diagnostics from a focus on dysfunction and disease to better measures of psychophysical function and health. Practical methods to define genotypes will be increasingly important and non-invasive nanotechnologies are needed to detect molecular changes that predate histopathology. Methods This is not a review nor meant to be comprehensive. Specific topics have been selected to illustrate the principles of important paradigm shifts that will influence the future of ophthalmic diagnostics. It is our impression that future evaluation of vision will go beyond visual acuity to assess ocular health in terms of psychophysical function. The definition of disease will incorporate genotype into what has historically been a phenotype-centric discipline. Non-invasive nanotechnologies will enable a paradigm shift from disease detection on a cellular level to a sub-cellular molecular level. Results Vision can be evaluated beyond visual acuity by measuring contrast sensitivity, color vision, and macular function, as these provide better insights into the impact of aging and disease. Distortions can be quantified and the psychophysical basis of vision can be better evaluated than in the past by designing tests that assess particular macular cell function(s). Advances in our understanding of the genetic basis of eye diseases will enable better characterization of ocular health and disease. Non-invasive nanotechnologies can assess molecular changes in the lens, vitreous, and macula that predate visible pathology. Oxygen metabolism and circulatory physiology are measurable indices of ocular health that can detect variations of physiology and early disease. Conclusions This overview of paradigm shifts in ophthalmology suggests that the future will see significant improvements in ophthalmic diagnostics. The selected topics illustrate the principles of these paradigm shifts and should serve as a guide to further

  15. Mycobacterium avium subsp. paratuberculosis antibody response, fecal shedding, and antibody cross-reactivity to Mycobacterium bovis in M. avium subsp. paratuberculosis-infected cattle herds vaccinated against Johne's disease.

    PubMed

    Tewari, Deepanker; Hovingh, Ernest; Linscott, Rick; Martel, Edmond; Lawrence, John; Wolfgang, David; Griswold, David

    2014-05-01

    Vaccination for Johne's disease with killed inactivated vaccine in cattle herds has shown variable success. The vaccine delays the onset of disease but does not afford complete protection. Johne's disease vaccination has also been reported to interfere with measurements of cell-mediated immune responses for the detection of bovine tuberculosis. Temporal antibody responses and fecal shedding of Mycobacterium avium subsp. paratuberculosis, the causative agent of Johne's disease, were measured in 2 dairy cattle herds using Johne's disease vaccine (Mycopar) over a period of 7 years. Vaccination against Johne's disease resulted in positive serum M. avium subsp. paratuberculosis antibody responses in both herds, and the responses persisted in vaccinated cattle up to 7 years of age. Some vaccinated animals (29.4% in herd A and 36.2% in herd B) showed no serological reactivity to M. avium subsp. paratuberculosis. M. avium subsp. paratuberculosis-specific antibody responses were also detected in milk from Johne's disease-vaccinated animals, but fewer animals (39.3% in herd A and 49.4% in herd B) had positive results with milk than with serum samples. With vaccination against M. avium subsp. paratuberculosis, fecal shedding in both dairy herds was reduced significantly (P < 0.001). In addition, when selected Johne's disease-vaccinated and -infected animals were investigated for serological cross-reactivity to Mycobacterium bovis, no cross-reactivity was observed.

  16. The Synthesis Paradigm in Genetics

    PubMed Central

    Rice, William R.

    2014-01-01

    Experimental genetics with model organisms and mathematically explicit genetic theory are generally considered to be the major paradigms by which progress in genetics is achieved. Here I argue that this view is incomplete and that pivotal advances in genetics—and other fields of biology—are also made by synthesizing disparate threads of extant information rather than generating new information from experiments or formal theory. Because of the explosive expansion of information in numerous “-omics” data banks, and the fragmentation of genetics into numerous subdisciplines, the importance of the synthesis paradigm will likely expand with time. PMID:24496401

  17. The synthesis paradigm in genetics.

    PubMed

    Rice, William R

    2014-02-01

    Experimental genetics with model organisms and mathematically explicit genetic theory are generally considered to be the major paradigms by which progress in genetics is achieved. Here I argue that this view is incomplete and that pivotal advances in genetics--and other fields of biology--are also made by synthesizing disparate threads of extant information rather than generating new information from experiments or formal theory. Because of the explosive expansion of information in numerous "-omics" data banks, and the fragmentation of genetics into numerous subdisciplines, the importance of the synthesis paradigm will likely expand with time.

  18. Emergence of life: Physical chemistry changes the paradigm.

    PubMed

    Spitzer, Jan; Pielak, Gary J; Poolman, Bert

    2015-06-10

    Origin of life research has been slow to advance not only because of its complex evolutionary nature (Franklin Harold: In Search of Cell History, 2014) but also because of the lack of agreement on fundamental concepts, including the question of 'what is life?'. To re-energize the research and define a new experimental paradigm, we advance four premises to better understand the physicochemical complexities of life's emergence: (1) Chemical and Darwinian (biological) evolutions are distinct, but become continuous with the appearance of heredity. (2) Earth's chemical evolution is driven by energies of cycling (diurnal) disequilibria and by energies of hydrothermal vents. (3) Earth's overall chemical complexity must be high at the origin of life for a subset of (complex) chemicals to phase separate and evolve into living states. (4) Macromolecular crowding in aqueous electrolytes under confined conditions enables evolution of molecular recognition and cellular self-organization. We discuss these premises in relation to current 'constructive' (non-evolutionary) paradigm of origins research - the process of complexification of chemical matter 'from the simple to the complex'. This paradigm artificially avoids planetary chemical complexity and the natural tendency of molecular compositions toward maximum disorder embodied in the second law of thermodynamics. Our four premises suggest an empirical program of experiments involving complex chemical compositions under cycling gradients of temperature, water activity and electromagnetic radiation.

  19. Comparative transcriptional analysis of human macrophages exposed to animal and human isolates of Mycobacterium avium subspecies paratuberculosis with diverse genotypes.

    PubMed

    Motiwala, Alifiya S; Janagama, Harish K; Paustian, Michael L; Zhu, Xiaochun; Bannantine, John P; Kapur, Vivek; Sreevatsan, Srinand

    2006-11-01

    Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease in animals and has been hypothesized to be associated with Crohn's disease in humans. Recently, M. avium subsp. paratuberculosis isolates recovered from Crohn's disease patients were shown to have limited diversity, implying the existence of human disease-associated genotypes and strain sharing with animals (A. H. Ghadiali et al., J. Clin. Microbiol. 42:5345-5348, 2004). To explore whether these genotypic differences or similarities among human and animal isolates translated to functionally significant attributes such as variance in host preference and/or difference in magnitude of infections, we performed a global scale analysis of M. avium subsp. paratuberculosis isolates that were representative of different genotypes and host species using DNA microarrays. Genome-wide characterization of the transcriptional changes was carried out using a human monocytic cell line (THP-1 cells) in response to different genotypes of M. avium subsp. paratuberculosis isolates recovered from various hosts. We identified several differentially expressed genes during early intracellular infection, including those involved in common canonical pathways such as NF-kappaB, interleukin-6 (IL-6), mitogen-activated protein kinase/extracellular signal-regulated kinase, and Jun N-terminal protein kinase signaling, as well as genes involved in T helper type 1 (Th1) responses (such as CCL5 ligand) and those that encode several proinflammatory cytokines and chemokine receptors. The cattle and human isolates of M. avium subsp. paratuberculosis, regardless of their short sequence repeat (SSR) genotype, induced similar global gene expression patterns in THP-1 cells. They differentially regulated genes necessary for cell survival without causing major alterations in proinflammatory genes. In contrast, the sheep isolates representing diverse SSR genotypes closely resembled the global gene expression pattern of an M

  20. Integrating Essential Components of Quality Improvement into a New Paradigm for Continuing Education

    ERIC Educational Resources Information Center

    Van Hoof, Thomas J.; Meehan, Thomas P.

    2011-01-01

    Continuing education (CE) that strives to improve patient care in a complex health care system requires a different paradigm than CE that seeks to improve clinician knowledge and competence in an educational setting. A new paradigm for CE is necessary in order to change clinician behavior and to improve patient outcomes in an increasingly…

  1. The Development of the Foundations of Modern Pedagogy: Paradigmal and Methodological Aspects of Research

    ERIC Educational Resources Information Center

    Dmitrenko, ?amara ?.; Lavryk, Tatjana V.; Yaresko, Ekaterina V.

    2015-01-01

    Changes in the various fields of knowledge influenced the pedagogical science. The article explains the structure of the foundations of modern pedagogy through paradigmal and methodological aspects. Bases of modern pedagogy include complex of paradigms, object and subject of science, general and specific principles, methods and technologies.…

  2. [Disinfection efficiency of peracetic acid, alone and in combination with hypochlorite, against Mycobacterium avium in drinking water].

    PubMed

    Schiavano, G F; Sisti, M; De Santi, M; Brandi, G

    2006-01-01

    Peracetic acid (PAA) is a disinfectant with a wide spectrum of antimicrobial activity, but little is known about the feasibility of using it in the field of drinking water treatment. The aim of this study has been assess disinfectant efficacy of PAA, alone or in combination with hypochlorite, against M. avium in drinking water M. avium is a common opportunistic pathogen in immunocompromised subjects that is able to survive and grow in drinking water distribution systems. In this study PAA did not show appreciable activity against the greater number of tested strains (16/21) up to 5 ppm of PAA, a weak activity was seen on 4 strains, while a significant reduction in viable cells (about 50%) was seen only on 1 strain after 48 h of treatment with 5 ppm of PAA. We also evidenced that M. avium was unaffected by chlorine concentration usually present in drinking water distribution system. Finally, the combination of PAA and sodium hypochlorite did not promote enhanced antimicrobial efficacy respect to the single disinfectants. In conclusion, our result would indicate that PAA is an unlikely candidate for the disinfection of drinking water from M. avium and further strategies are required to eliminate M. avium from drinking water system.

  3. Staff Development: A Gestalt Paradigm.

    ERIC Educational Resources Information Center

    Parsons, Michael H.

    Hagerstown Junior College, Maryland, has had a staff development program for the past five years. The major components have been evaluated, revised, and integrated into a gestalt paradigm--a total institutional thrust designed to insure that the goals of the college meet the challenges presented by the service area. Each component exists to foster…

  4. Ethnic Nationalism: Social Science Paradigms.

    ERIC Educational Resources Information Center

    Richmond, Anthony H.

    1987-01-01

    Reviews various theories which combine to produce a paradigm for the analysis of ethnic nationalism. Covers terminology confusion, biosocial theories, modernization theories, Marxist/Leninist theories, internal colonialism, ethnic pluralism, micro-social theories, system theories and multivariate models, development and modernization, power,…

  5. THE RETURN OF THE PARADIGM.

    ERIC Educational Resources Information Center

    BREND, RUTH M.

    TWO SIGNIFICANT ASPECTS OF LANGUAGE LEARNING, THE VERTICAL ORGANIZATION OF THE PARADIGM AND THE STUDENT'S ANALYTICAL ABILITY, HAVE BEEN OVERLOOKED IN FAVOR OF DEVELOPING CONVERSATIONAL SKILLS BY A HORIZONTAL APPROACH IN WHICH, FOR EXAMPLE, THE MATERIAL PRESENTS THE ACCUSATIVE CASE ONE DAY AND THE FIRST PERSON PRESENT OF ALL VERBS ON ANOTHER.…

  6. Paradigm Statements of Educational Objectives.

    ERIC Educational Resources Information Center

    Gray, Peter J.

    Five distinct format categories are used in this study to describe the form of educational objectives: clarity, range, level of abstractness, behavioralness, and observability. These form concepts are used to describe paradigm statements of three kinds of educational objectives: goals, intended learning outcomes, and behavioral evidence. Goals are…

  7. A new paradigm for practice education.

    PubMed

    Edmond, C B

    2001-05-01

    This paper explores the complex nature of professional practice. It suggests that educating for all practice disciplines is about to undergo a paradigm shift whereby the value of practical education and experience will be better understood, more rigorously analyzed and integrated with propositional knowledge in the construction of personal professional knowledge and identity. It relates this cross disciplinary position to the present problems of skills deficits which are evident in nurses at the point of registration and demonstrates how routinization and internalization of process and tacit knowledge can create problems for students and newly qualified staff nurses. It also suggests how this can be addressed. It discusses the present culture of 'clinical education by default', unavailability of mentors and resources, and general lack of formal collaborative structures between education and service institutions and suggests that the present system cannot sustain the complex demands, expectations and pace of the clinical context and the evolution of nursing practice. Clinical credibility is an issue as is the current heavy clinical workload of staff nurse mentors, and several collaborative clinical education models are outlined which ensure that staff nurses or resident clinical educators are available and can make clinical teaching their priority. History and the present crisis in nursing suggest that there is a case for mandatory collaborative education/service structures to ensure adequate funding and to monitor the effectiveness of selected models so that staff nurse mentors can work with lecturer colleagues to articulate and teach the complexities of clinical practice through related research. It is predicted that this collaborative approach is capable of addressing both the skills deficits and the wider intellectual challenge of developing a new paradigm of practice education and providing an integrated base for continuing professional development.

  8. Processing and presentation of an antigen of Mycobacterium avium require access to an acidified compartment with active proteases.

    PubMed Central

    Holsti, M A; Allen, P M

    1996-01-01

    We have generated a murine T-cell hybridoma, 1C9, which recognizes an antigen expressed by a virulent clinical isolate of Mycobacterium avium. Both peritoneal exudate macrophages and bone marrow-derived macrophages infected in vitro with M. avium process and present the antigen to the T-cell hybridoma. Gel filtration chromatography of a sonicate of M. avium followed by T-cell Western blotting (immunoblotting) demonstrated that the antigen recognized by hybridoma 1C9 is approximately 50 kDa. In addition, treatment of macrophages with the lysosomotropic agent chloroquine or with inhibitors of acid proteases inhibits processing and presentation of the antigen. These results indicate that the antigen must encounter an acidic compartment with active proteases for processing and presentation to occur. Our results are discussed in the context of our current understanding of how mycobacterial antigens are processed and presented by infected macrophages to T cells. PMID:8926074

  9. Optimization of a phage amplification assay to permit accurate enumeration of viable Mycobacterium avium subsp. paratuberculosis cells.

    PubMed

    Foddai, Antonio; Elliott, Christopher T; Grant, Irene R

    2009-06-01

    A commercially available phage amplification assay, FASTPlaqueTB (Biotec Laboratories, Ipswich, United Kingdom), when used according to the manufacturer's instructions, does not permit accurate enumeration of Mycobacterium avium subsp. paratuberculosis. The aim of this study was to optimize the phage amplification assay conditions to permit accurate quantification of viable M. avium subsp. paratuberculosis cells. The burst time for M. avium subsp. paratuberculosis was initially determined to inform decisions about optimal incubation time before plating, and then other test parameters were altered to evaluate how the correlation between plaque and colony counts was affected. The D29 mycobacteriophage replicates more slowly in M. avium subsp. paratuberculosis than in Mycobacterium smegmatis (used to optimize the commercial test originally), and the mean burst time for four M. avium subsp. paratuberulosis strains was 210 +/- 36.8 min at 37 degrees C compared to 63 +/- 17.5 min for M. smegmatis mc(2) 155. To achieve 100% correlation between plaque and colony counts, the optimized phage assay includes the following: (i) resuspension of the samples to be tested in Middlebrook 7H9 broth containing 10% oleic acid-albumin-dextrose-catalase and 2 mM calcium chloride, followed by overnight incubation at 37 degrees C before performance of the phage assay; (ii) a 2-h incubation of the sample with D29 mycobacteriophage before viricide treatment; and (iii) a further 90-min incubation after viricide treatment and neutralization up to the burst time (total incubation time, 210 min) before plating with M. smegmatis mc(2) 155 in 7H9 agar. The optimized phage amplification assay was able to detect 1 to 10 CFU/ml of M. avium subsp. paratuberculosis in spiked milk or broth within 48 h, as demonstrated by the results of several blind trials.

  10. Connecting traditional sciences with the OLAP and data mining paradigms

    NASA Astrophysics Data System (ADS)

    Guergachi, Aziz A.

    2003-03-01

    The paradigms of OLAP, multidimensional modeling and data mining have first emerged in the areas of market analysis and finance to address various needs of people working in these areas. Does this mean that they are useful and applicable in these areas only? Or, can they also be applicable in the other more traditional areas of science and engineering? What characterize the systems for which these paradigms are suitable? What are the goals of these paradigms? How do they relate to the traditional body of knowledge that has been developed throughout the centuries in the areas of mathematics, statistics, systems science and engineering? Where, how and to what extent can we leverage the conventional wisdom that has been accumulated in the aforementioned disciplines to develop a foundational basis for the above paradigms? The goal of this paper is to address these questions at the foundational level. We argue that the paradigms of OLAP, multidimensional modeling and data mining can also be applied successfully to complex engineering systems, such as membrane-based water/wastewater treatment plants, for example. We develop mathematically-based axiomatic definition of the concepts of 'dimension,' 'dimension level,' 'dimension hierarchy' and 'measure' using set theory and equivalence relations.

  11. High-Throughput Direct Fecal PCR Assay for Detection of Mycobacterium avium subsp. paratuberculosis in Sheep and Cattle

    PubMed Central

    Waldron, Anna M.; Galea, Francesca; Whittington, Ann-Michele; Saunders, Vanessa F.; Begg, Douglas J.; de Silva, Kumudika; Purdie, Auriol C.; Whittington, Richard J.

    2014-01-01

    Johne's disease (JD) is a chronic enteric disease caused by Mycobacterium avium subsp. paratuberculosis that affects ruminants. Transmission occurs by the fecal-oral route. A commonly used antemortem diagnostic test for the detection of M. avium subsp. paratuberculosis in feces is liquid culture; however, a major constraint is the 2- to 3-month incubation period needed for this method. Rapid methods for the detection of M. avium subsp. paratuberculosis based on PCR have been reported, but comprehensive validation data are lacking. We describe here a new test, the high-throughput-Johnes (HT-J), to detect M. avium subsp. paratuberculosis in feces. Its diagnostic accuracy was compared with that of liquid radiometric (Bactec) fecal culture using samples from cattle (1,330 samples from 23 herds) and sheep (596 samples from 16 flocks). The multistage protocol involves the recovery of M. avium subsp. paratuberculosis cells from a fecal suspension, cell rupture by bead beating, extraction of DNA using magnetic beads, and IS900 quantitative PCR. The limit of detection of the assay was 0.0005 pg, and the limit of quantification was 0.005 pg M. avium subsp. paratuberculosis genomic DNA. Only M. avium subsp. paratuberculosis was detected from a panel of 51 mycobacterial isolates, including 10 with IS900-like sequences. Of the 549 culture-negative fecal samples from unexposed herds and flocks, 99% were negative in the HT-J test, while 60% of the bovine- and 84% of the ovine-culture-positive samples were positive in the HT-J test. As similar total numbers of samples from M. avium subsp. paratuberculosis-exposed animals were positive in culture and HT-J tests in both species, and as the results of a McNemar's test were not significant, these methods probably have similar sensitivities, but the true diagnostic sensitivities of these tests are unknown. These validation data meet the consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis and

  12. High-throughput direct fecal PCR assay for detection of Mycobacterium avium subsp. paratuberculosis in sheep and cattle.

    PubMed

    Plain, Karren M; Marsh, Ian B; Waldron, Anna M; Galea, Francesca; Whittington, Ann-Michele; Saunders, Vanessa F; Begg, Douglas J; de Silva, Kumudika; Purdie, Auriol C; Whittington, Richard J

    2014-03-01

    Johne's disease (JD) is a chronic enteric disease caused by Mycobacterium avium subsp. paratuberculosis that affects ruminants. Transmission occurs by the fecal-oral route. A commonly used antemortem diagnostic test for the detection of M. avium subsp. paratuberculosis in feces is liquid culture; however, a major constraint is the 2- to 3-month incubation period needed for this method. Rapid methods for the detection of M. avium subsp. paratuberculosis based on PCR have been reported, but comprehensive validation data are lacking. We describe here a new test, the high-throughput-Johnes (HT-J), to detect M. avium subsp. paratuberculosis in feces. Its diagnostic accuracy was compared with that of liquid radiometric (Bactec) fecal culture using samples from cattle (1,330 samples from 23 herds) and sheep (596 samples from 16 flocks). The multistage protocol involves the recovery of M. avium subsp. paratuberculosis cells from a fecal suspension, cell rupture by bead beating, extraction of DNA using magnetic beads, and IS900 quantitative PCR. The limit of detection of the assay was 0.0005 pg, and the limit of quantification was 0.005 pg M. avium subsp. paratuberculosis genomic DNA. Only M. avium subsp. paratuberculosis was detected from a panel of 51 mycobacterial isolates, including 10 with IS900-like sequences. Of the 549 culture-negative fecal samples from unexposed herds and flocks, 99% were negative in the HT-J test, while 60% of the bovine- and 84% of the ovine-culture-positive samples were positive in the HT-J test. As similar total numbers of samples from M. avium subsp. paratuberculosis-exposed animals were positive in culture and HT-J tests in both species, and as the results of a McNemar's test were not significant, these methods probably have similar sensitivities, but the true diagnostic sensitivities of these tests are unknown. These validation data meet the consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis and

  13. An experimental paradigm for team decision processes

    NASA Technical Reports Server (NTRS)

    Serfaty, D.; Kleinman, D. L.

    1986-01-01

    The study of distributed information processing and decision making is presently hampered by two factors: (1) The inherent complexity of the mathematical formulation of decentralized problems has prevented the development of models that could be used to predict performance in a distributed environment; and (2) The lack of comprehensive scientific empirical data on human team decision making has hindered the development of significant descriptive models. As a part of a comprehensive effort to find a new framework for multihuman decision making problems, a novel experimental research paradigm was developed involving human terms in decision making tasks. Attempts to construct parts of an integrated model with ideas from queueing networks, team theory, distributed estimation and decentralized resource management are described.

  14. Employee discipline: a changing paradigm.

    PubMed

    Raper, J L; Myaya, S N

    1993-12-01

    To increase the receptiveness of health care supervisors to a broader meaning of discipline and to simulate investigation of nontraditional methods of encouragement to employees who fail to meet minimum standards of conduct and thereby negatively affect the quality of patient care, a subjectively realistic view of the implications of the traditional punitive disciplinary paradigm is presented. Through the use of a case study, the authors present, explain, and apply the contemporary concept of discipline without punishment as first described by J. Huberman.

  15. The Afrocentric Paradigm: Contours and Definitions.

    ERIC Educational Resources Information Center

    Mazama, Ama

    2001-01-01

    Defines and describes Afrocentricity, suggesting that Afrocentricity within the academic context is best understood as a paradigm. Explains how Afrocentricity meets the definition of a paradigm, examining the affective, cognitive, and conative aspects of the Afrocentric paradigm (metaphysical and sociological) and looking at the structural and…

  16. Two Essays on the Learning Paradigm.

    ERIC Educational Resources Information Center

    Doud, Robert E.

    This document contains two essays, both of which discuss the ascendancy of the learning paradigm over the teaching paradigm. "Philosophy and the Learning Paradigm" reviews the effects of post-modernism on student learning with regard to loss of authority in the classroom, lack of academic standards in writing, and perceptions of…

  17. Poverty eradication: a new paradigm.

    PubMed

    Pethe, V P

    1998-08-01

    This article offers a new paradigm for eradicating poverty in India. It was assumed incorrectly by Mahatma Gandhi that a good society without mass poverty would follow after independence. India copied Western models of development and developed giant factories, big dams, and megacities. Agriculture did not expand the number of jobs for people. The Western paradigm failed in India because of the false assumption of "trickle down" of income to the masses. The targeted programs to the poor did not directly benefit enough of the poor. Mega-industrialization led to reduced employment and higher skill needs. The model failed mainly because it was a proxy and relied on indirect ways of reaching the poor. The models failed to be adapted to conditions in India. The Swadeshi paradigm is a direct model for addressing mass poverty. Poverty is affected by immediate, intermediate, and ultimate determinants. Poverty begets social and economic problems, such as ignorance, ill health, high fertility, unemployment, and crime. In India and developing countries, mass poverty results from under use of human resources; lack of equal opportunities; and an outdated non-egalitarian social structure, an unjust global economic order, human cruelty, and erosion of ethical values. Indians are squandering their precious resources mimicking Western consumerism. Poverty leads to rapid population growth. People become productive assets with universal literacy, compulsory and free education, health services and sanitation, vocational training, and work ethics. India needs people-oriented policies with less emphasis on capital accumulation.

  18. [Pulmonary Mycobacterium avium-intracellulare complex disease that presented multiple nodular shadows rapidly].

    PubMed

    Fujiwara, Kiyohiro

    2009-09-01

    The patient was 81-year-old woman diagnosed with lung cancer who underwent upper right lobectomy in January 2002. Computed tomography (CT) of the thorax showed a mass shadow presenting rapid-growing in the left S3 in August, 2008. The size of the mass shadow in the left S3 increased on day 16 after hospitalization, and a nodular shadow appeared in the left S(1+2). The bronchial washing specimen showed acid-fast bacilli identified as Mycobacterium intracellulare by deoxyribonucleic acid (DNA) -DNA hybridization (DDH). The patient showed radiological improvement following combination chemotherapy with rifampicin, ethambutol and clarithromycin.

  19. Detection of Legionella, L. pneumophila and Mycobacterium avium complex (MAC) along potable water distribution pipelines.

    PubMed

    Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

    2014-07-18

    Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use.

  20. Fluorescent acid-fast microscopy for measuring phagocytosis of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum by Tetrahymena pyriformis and their intracellular growth.

    PubMed

    Strahl, E D; Gillaspy, G E; Falkinham, J O

    2001-10-01

    Fluorescent acid-fast microscopy (FAM) was used to enumerate intracellular Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum in the ciliated phagocytic protozoan Tetrahymena pyriformis. There was a linear relationship between FAM and colony counts of M. avium cells both from cultures and within protozoa. The Ziehl-Neelsen acid-fast stain could not be used to enumerate intracellular mycobacteria because uninfected protozoa contained acid-fast, bacterium-like particles. Starved, 7-day-old cultures of T. pyriformis transferred into fresh medium readily phagocytized M. avium, M. intracellulare, and M. scrofulaceum. Phagocytosis was rapid and reached a maximum in 30 min. M. avium, M. intracellulare, and M. scrofulaceum grew within T. pyriformis, increasing by factors of 4- to 40-fold after 5 days at 30 degrees C. Intracellular M. avium numbers remained constant over a 25-day period of growth (by transfer) of T. pyriformis. Intracellular M. avium cells also survived protozoan encystment and germination. The growth and viability of T. pyriformis were not affected by mycobacterial infection. The results suggest that free-living phagocytic protozoa may be natural hosts and reservoirs for M. avium, M. intracellulare, and M. scrofulaceum.

  1. PRESENCE OF MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS IN ALPACAS (LAMA PACOS) INHABITING THE CHILEAN ALTIPLANO.

    PubMed

    Salgado, Miguel; Sevilla, Iker; Rios, Carolina; Crossley, Jorge; Tejeda, Carlos; Manning, Elizabeth

    2016-03-01

    Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of paratuberculosis. The organism causes disease in both domestically managed and wild ruminant species. South American camelids have a long, shared history with indigenous people in the Andes. Over the last few decades, increasing numbers of alpacas were exported to numerous countries outside South America. No paratuberculosis surveillance has been reported for these source herds. In this study, individual fecal samples from 85 adult alpacas were collected from six separate herds in the Chilean Altiplano. A ParaTB mycobacterial growth indicator tube (MGIT) liquid culture of each individual fecal sample, followed by real-time polymerase chain reaction (PCR) protocol was used for confirmation. DNA extracts from a subset of confirmed MAP isolates were subjected to mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing. Fifteen alpaca were fecal culture test-positive. Five false-positive culture samples were negative on PCR analysis for Mycobacterium avium subsp. avium (MAA), Mycobacterium bovis (M. bovis), and the 16 S rDNA gene. Three MAP isolates subset-tested belonged to the same MIRU-VNTR type, showing four repeats for TR292 (locus 1) in contrast to the three repeats typical of the MAP reference strain K10. The number of repeats found in the remaining loci was identical to that of the K10 strain. It is not known how nor when MAP was introduced into the alpaca population in the Chilean Altiplano. The most plausible hypothesis to explain the presence of MAP in these indigenous populations is transmission by contact with infected domestic small ruminant species that may on occasion share pastures or range with alpacas. Isolation of this mycobacterial pathogen from such a remote region suggests that MAP has found its way beyond the confines of intensively managed domestic agriculture premises.

  2. About hypotheses and paradigms: exploring the Discreetness-Chance Paradigm.

    PubMed

    Kaellis, Eugene

    2006-01-01

    Hypotheses generally conform to paradigms which, over time, change, usually tardily, after they have become increasingly difficult to sustain under the impact of non-conforming evidence and alternative hypotheses, but more important, when they no longer are comfortably ensconced in the surrounding social-economic-political-cultural milieu. It is asserted that this milieu is the most important factor in shaping scientific theorizing. Some examples are cited: the rejection of the evidence that the world orbits around the sun (suspected by Pythagoras) in favor of centuries-long firm adherence to the Ptolemaic geocentric system; the early acceptance of Natural Selection in spite of its tautological essence and only conjectural supporting evidence, because it justified contemporaneous social-political ideologies as typified by, e.g., Spencer and Malthus. Economic, social, and cultural factors are cited as providing the ground, i.e., ideational substrate, for what is cited as the Discreetness-Chance Paradigm (DCP), that has increasingly dominated physics, biology, and medicine for over a century and which invokes small, discrete packets of energy/matter (quanta, genes, microorganisms, aberrant cells) functioning within an environment of statistical, not determined, causality. There is speculation on a possible paradigmatic shift from the DCP, which has fostered the proliferation, parallel with ("splitting") taxonomy, of alleged individual disease entities, their diagnoses, and, when available, their specific remedies, something particularly prominent in, e.g., psychiatry's Diagnostic and Statistical Manual, a codified compendium of alleged mental and behavioral disorders, but evident in any textbook of diagnosis and treatment of physical ailments. This presumed paradigm shift may be reflected in Western medicine, presently increasingly empirical and atomized, towards a growing acceptance of a more generalized, subject-oriented, approach to health and disease, a non

  3. Molecular identification of Mycobacterium avium subspecies paratuberculosis in oral biopsies of Crohn’s disease patients

    PubMed Central

    2013-01-01

    Oral lesions may be found in patients with Crohn’s disease (CD), in a percentage up to 20%. The aim of this study was to investigate a possible relationship between Mycobacterium avium subsp. paratuberculosis (MAP) and oral lesions in CD patients. 23 oral biopsies were examined performing IS900 Nested PCR; 9 of them were positive: 8 from CD patients and 1 from a control. Our purpose is to go on with this study, amplifying the number of subjects examined and testing subjects with oral lesions related to diseases other than CD to verify the specific association between MAP and oral lesions in CD patients. PMID:23842143

  4. Systemic infection of Mycobacterium avium subspecies hominissuis and fungus in a pet dog.

    PubMed

    Kim, Myung-Chul; Kim, JaeMyung; Kang, WoonKi; Jang, Yunho; Kim, Yongbaek

    2016-01-01

    A 3-year-old neutered female poodle with a long history of dermatophytic skin disease was presented with lethargy, anorexia and progressive weight loss. Abdominal ultrasonography revealed markedly enlarged mesenteric lymph nodes and multiple hypoechoic foci in the spleen. Cytology of the mesenteric lymph nodes and spleen showed granulomatous inflammation with fungal organisms and negatively stained intracytoplasmic bacterial rods consistent with Mycobacteria spp. Based on culture, multiplex polymerase chain reaction and sequence analysis, the bacterium was identified as Mycobacterium avium subspecies hominissuis. Despite treatment with antibiotics, the dog's condition deteriorated, and it died approximately 3 weeks after first presentation.

  5. Systemic infection of Mycobacterium avium subspecies hominissuis and fungus in a pet dog

    PubMed Central

    KIM, Myung-Chul; KIM, JaeMyung; KANG, WoonKi; JANG, Yunho; KIM, Yongbaek

    2015-01-01

    A 3-year-old neutered female poodle with a long history of dermatophytic skin disease was presented with lethargy, anorexia and progressive weight loss. Abdominal ultrasonography revealed markedly enlarged mesenteric lymph nodes and multiple hypoechoic foci in the spleen. Cytology of the mesenteric lymph nodes and spleen showed granulomatous inflammation with fungal organisms and negatively stained intracytoplasmic bacterial rods consistent with Mycobacteria spp. Based on culture, multiplex polymerase chain reaction and sequence analysis, the bacterium was identified as Mycobacterium avium subspecies hominissuis. Despite treatment with antibiotics, the dog’s condition deteriorated, and it died approximately 3 weeks after first presentation. PMID:26412202

  6. Molecular identification of Mycobacterium avium subspecies paratuberculosis in oral biopsies of Crohn's disease patients.

    PubMed

    Molicotti, Paola; Scanu, Antonio M; Lumbau, Aurea; Cannas, Sara; Bua, Alessandra; Lugliè, Pietrina; Zanetti, Stefania

    2013-07-10

    Oral lesions may be found in patients with Crohn's disease (CD), in a percentage up to 20%. The aim of this study was to investigate a possible relationship between Mycobacterium avium subsp. paratuberculosis (MAP) and oral lesions in CD patients. 23 oral biopsies were examined performing IS900 Nested PCR; 9 of them were positive: 8 from CD patients and 1 from a control. Our purpose is to go on with this study, amplifying the number of subjects examined and testing subjects with oral lesions related to diseases other than CD to verify the specific association between MAP and oral lesions in CD patients.

  7. What Role Does Mycobacterium avium subsp. paratuberculosis Play in Crohn's Disease?

    PubMed

    Bach, Horacio

    2015-02-01

    Crohn's disease (CD) is a chronic, debilitating inflammatory bowel disease with no etiological agent yet identified. Studies have demonstrated that the bacterium Mycobacterium avium subsp. paratuberculosis (MAP) is present in a high percentage of CD patients. Although MAP has been isolated from human specimens, current techniques fail to show the presence of MAP in 100 % of tissues or biopsies obtained from CD patient lesions, and thus MAP cannot meet Koch's postulate as the etiological agent of CD. In this report, the effect of genetic and immune factors as well as the presence of MAP as a potential environmental factor is analyzed.

  8. Cutaneous gallium uptake in patients with AIDS with mycobacterium avium-intracellulare septicemia

    SciTech Connect

    Allwright, S.J.; Chapman, P.R.; Antico, V.F.; Gruenewald, S.M.

    1988-07-01

    Gallium imaging is increasingly being used for the early detection of complications in patients with AIDS. A 26-year-old homosexual man who was HIV antibody positive underwent gallium imaging for investigation of possible Pneumocystis carinii pneumonia. Widespread cutaneous focal uptake was seen, which was subsequently shown to be due to mycobacterium avium-intracellulare (MAI) septicemia. This case demonstrates the importance of whole body imaging rather than imaging target areas only, the utility of gallium imaging in aiding the early detection of clinically unsuspected disease, and shows a new pattern of gallium uptake in disseminated MAI infection.

  9. Culture- and quantitative IS900 real-time PCR-based analysis of the persistence of Mycobacterium avium subsp. paratuberculosis in a controlled dairy cow farm environment.

    PubMed

    Moravkova, M; Babak, V; Kralova, A; Pavlik, I; Slana, I

    2012-09-01

    The aim of this study was to monitor the persistence of Mycobacterium avium subsp. paratuberculosis in environmental samples taken from a Holstein farm with a long history of clinical paratuberculosis. A herd of 606 head was eradicated, and mechanical cleaning and disinfection with chloramine B with ammonium (4%) was carried out on the farm; in the surrounding areas (on the field and field midden) lime was applied. Environmental samples were collected before and over a period of 24 months after destocking. Only one sample out of 48 (2%) examined on the farm (originating from a waste pit and collected before destocking) was positive for M. avium subsp. paratuberculosis by cultivation on solid medium (Herrold's egg yolk medium). The results using real-time quantitative PCR (qPCR) showed that a total of 81% of environmental samples with an average mean M. avium subsp. paratuberculosis cell number of 3.09 × 10(3) were positive for M. avium subsp. paratuberculosis before destocking compared to 43% with an average mean M. avium subsp. paratuberculosis cell number of 5.86 × 10(2) after 24 months. M. avium subsp. paratuberculosis-positive samples were detected in the cattle barn as well as in the calf barn and surrounding areas. M. avium subsp. paratuberculosis was detected from different matrices: floor and instrument scrapings, sediment, or scraping from watering troughs, waste pits, and cobwebs. M. avium subsp. paratuberculosis DNA was also detected in soil and plants collected on the field midden and the field 24 months after destocking. Although the proportion of positive samples decreased from 64% to 23% over time, the numbers of M. avium subsp. paratuberculosis cells were comparable.

  10. Construction of chimeric phagosomes that shelter Mycobacterium avium and Coxiella burnetii (phase II) in doubly infected mouse macrophages: an ultrastructural study.

    PubMed

    de Chastellier, C; Thibon, M; Rabinovitch, M

    1999-08-01

    Dual infection of cells may divert pathogens to intracellular compartments different from those occupied in mono-infected cells. In the present studies, mouse bone marrow in vitro-derived macrophages were first infected with virulent Mycobacterium avium, which are normally singly lodged within tight phagosomes. These phagosomes do not mature; they undergo homotypic fusion with early endosomes and do not fuse with lysosomes. Seven days later, the cultures were superinfected with phase II (non-virulent) Coxiella burnetii, organisms sheltered in lysosome- (or prelysosome)-like, multi-occupancy phagosomes. The latter can attain large size and engage in efficient homo- and heterotypic fusion with other phagosomes. Cultures were fixed for transmission electron microscopy 6, 12, 24, and 48 h later. Other M. avium-infected cultures were superinfected with amastigotes of the trypanosomatid flagellate Leishmania amazonensis, which are also sheltered in lysosome- (or prelysosome)-like multi-occupancy vacuoles, and fixed at the same time periods. Chimeric phagosomes containing both M. avium and C. burnetii, were found already at 6 h and the proportion of M. avium that colocalized with C. burnetii in the same phagosomes reached over 90% after 48 h. In such phagosomes, both organisms were ultrastructurally well preserved. In contrast, colocalization of M. avium and L. amazonensis was rarely found. Speculative scenarios that could underlie the formation of chimeric phagosomes could involve delayed maturation of C. burnetii-containing phagosomes in presence of M. avium, which would allow for fusion of C. burnetii- and M. avium-containing phagosomes; the production, by C. burnetii, of molecules that upregulate the fusion of M. avium-containing phagosomes with those that contain C. burnetii; and the secretion of factors that could favour the survival of M. avium within chimeric vacuoles.

  11. Enabling a New Planning and Scheduling Paradigm

    NASA Technical Reports Server (NTRS)

    Jaap, John; Davis, Elizabeth

    2004-01-01

    without the intervention of a scheduling expert. The algorithm is tuned for the constraint hierarchies and the complex temporal relationships provided by the modeling schema. It has an extensive search algorithm which can exploit timing flexibilities and constraint and relationship options. (3) A web-based architecture allows multiple remote users to simultaneously model science and technology requirements and other users to model vehicle and hardware characteristics. The architecture allows the users to submit scheduling requests directly to the scheduling engine and immediately see the results. These three components are integrated so that science and technology experts with no knowledge of the vehicle or hardware subsystems and no knowledge of the internal workings of the scheduling engine have the ability to build and submit scheduling requests and see the results. The immediate feedback will hone the users' modeling skills and ultimately enable them to produce the desired timeline. This paper summarizes the three components of the enabling technology and describes how this technology would make a new paradigm possible.

  12. Bayesian evidence and predictivity of the inflationary paradigm

    NASA Astrophysics Data System (ADS)

    Gubitosi, Giulia; Lagos, Macarena; Magueijo, João; Allison, Rupert

    2016-06-01

    In this paper we consider the issue of paradigm evaluation by applying Bayes' theorem along the following nested hierarchy of progressively more complex structures: i) parameter estimation (within a model), ii) model selection and comparison (within a paradigm), iii) paradigm evaluation. In such a hierarchy the Bayesian evidence works both as the posterior's normalization at a given level and as the likelihood function at the next level up. Whilst raising no objections to the standard application of the procedure at the two lowest levels, we argue that it should receive a considerable modification when evaluating paradigms, when testability and fitting data are equally important. By considering toy models we illustrate how models and paradigms that are difficult to falsify are always favoured by the Bayes factor. We argue that the evidence for a paradigm should not only be high for a given dataset, but exceptional with respect to what it would have been, had the data been different. With this motivation we propose a measure which we term predictivity, as well as a prior to be incorporated into the Bayesian framework, penalising unpredictivity as much as not fitting data. We apply this measure to inflation seen as a whole, and to a scenario where a specific inflationary model is hypothetically deemed as the only one viable as a result of information alien to cosmology (e.g. Solar System gravity experiments, or particle physics input). We conclude that cosmic inflation is currently hard to falsify, but that this could change were external/additional information to cosmology to select one of its many models. We also compare this state of affairs to bimetric varying speed of light cosmology.

  13. Isolation of Mycobacterium avium subspecies paratuberculosis Reactive T-cells from Intestinal Biopsies of Crohn's Disease Patients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crohn’s disease (CD) is a chronic granulomatous inflammation of the intestine. The etiology is still unknown. One hypothesis is that CD is caused by infection with Mycobacterium avium subspecies paratuberculosis (MAP) in genetically predisposed individuals. MAP causes a similar disease in ruminants,...

  14. CD4 T Cells From Intestinal Biopsies of Crohn's Disease Patients React to Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The role of Mycobacterium avium subspecies paratuberculosis (MAP) in Crohn’s disease (CD) remains controversial. One issue that has been raised is the lack of data showing a cellular immune response to MAP. Earlier studies have mostly focused on responses in peripheral blood which have several limit...

  15. COMPARISON OF MYCOBACTERIUM AVIUM ISOLATES FROM A DRINKING WATER DISTRIBUTION SYSTEM AND FROM THE POPULATION SERVED BY THE SYSTEM

    EPA Science Inventory

    Background: Current evidence suggests that drinking water, soil, and produce are potential sources of Mycobacterium avium infections, a pathogen not known to be transmitted person-to-person.

    Methods: We sampled water during 2000-2002 from a large municipal drinking water ...

  16. A Novel Cell Wall Lipopeptide Is Important for Biofilm Formation and Pathogenicity of Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofilm formation by pathogenic bacteria plays a key role in their pathogenesis. Previously, the pstA gene was shown to be involved in the virulence of Mycobacterium avium subspecies paratuberculosis (M. ap), the causative agent of Johne's disease in cattle and a potential risk factor for Crohn's d...

  17. Optimization of methods for the detection of Mycobacterium avium subsp. paratuberculosis in milk and colostrum of naturally infected dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) is primarily shed into the feces but it has also been isolated from the milk and colostrum of cows. Because of this, there exists concern about transfer of the organism from dam to calf and about the prevalence of MAP in the milk supply. The prevalen...

  18. Optimization of methods for the detection of Mycobacterium avium subsp. paratuberculosis in milk and colostrum of naturally infected dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two decontamination chemicals, hexadecylpyridinium choride (HPC) and N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH), were compared for their efficacy of reducing the growth of non-specific microorganisms in milk while minimally affecting the recovery of Mycobacterium avium subsp. paratuberculosis ...

  19. Shedding of Mycobacterium avium subsp. paratuberculosis into milk and colostrum of naturally infected dairy cows over complete lactation cycles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The primary mode of transmission of Mycobacterium avium subsp. paratuberculosis (MAP) is fecal-oral. However, MAP is also shed into the milk and colostrum of infected cows. The objective of this study was to identify if an association exists between stage of MAP infection and days in lactation with ...

  20. MOLECULAR COMPARISON OF MYCOBACTERIUM AVIUM ISOLATED FROM A FRINKING WATER DISTRIBUTION SYSTEM AND FROM THE POPULATION SERVED BY THE SYSTEM

    EPA Science Inventory

    There is evidence that drinking water, soil, and produce may be sources of Mycobacterium avium infections, a pathogen not known to be transmitted person-to-person. We sampled water from a large municipal drinking water distribution system in which surface source water is used. M...

  1. Early Immune Markers Associated with Experimental Mycobacterium avium subsp. paratuberculosis (MAP) Infection in a Neonatal Calf Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to observe early markers of cell-mediated immunity in naïve calves infected with Mycobacterium avium subsp. paratuberculosis (MAP) and how expression of these markers evolved over the 12-month period of infection. Methods of experimental infection included: Control (n...

  2. Analysis of Mycobacterium avium subspecies paratuberculosis mutant libraries reveals loci-dependent transposition biases and strategies to novel mutant discovery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP), the etiologic agent of Johne’s disease, is one of the most important bacterial pathogens in ruminants. The lack of efficacious control measures demands a thorough understanding of MAP pathogenesis to develop new vaccines and diagnostic tests. The ge...

  3. Antigenicity of recombinant maltose binding protein-Mycobacterium avium subsp. paratuberculosis fusion proteins with and without factor Xa cleaving

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp paratuberculosis (MAP) causes Johne’s disease (JD) in ruminants. Proteomic studies have shown that MAP expresses certain proteins when exposed to in vitro physiological stress conditions similar to the conditions experienced within a host during natural infection. Such prot...

  4. Characterization of the inflammatory phenotype of Mycobacterium avium subspecies paratuberculosis using a novel cell culture passage model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the pathogenic mechanisms and host responses to Johne’s disease, a chronic enteritis of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP), is complicated by the multifaceted disease progression, late-onset host reaction, and the lack of ex vivo infection models ...

  5. Analysis of Mycobacterium avium subsp. paratuberculosis mutant libraries reveals loci-dependent transcription biases and strategies to novel mutant discovery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of Johne’s disease in ruminants and it has been implicated as a cause of Crohn’s disease in humans. The generation of comprehensive random mutant banks by transposon mutagenesis is a fundamental wide genomic technology utilized...

  6. Evaluation of eight live attenuated vaccine candidates for protection against challenge with virulent Mycobacterium avium subspecies paratuberculosis in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), which results in serious economic losses worldwide in farmed livestock such as cattle, sheep and goats. To control this disease, an effective vaccine with minimal adverse effects is needed. In order to identify a live va...

  7. Divergent cellular responses during asymptomatic subclinical and clinical states of disease in cows naturally infected with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection of the host with Mycobacterium avium subsp. paratuberculosis (MAP) results in a chronic and progressive enteritis that traverses both subclinical and clinical stages. The mechanism(s) for the shift from asymptomatic subclinical disease state to advanced clinical disease are not fully under...

  8. ZAP-70, CTLA-4 and proximal T cell receptor signaling in cows infected with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Paratuberculosis is a chronic intestinal disease of ruminant animals caused by Mycobacterium avium subsp. paratuberculosis (MAP). A hallmark of paratuberculosis is a transition from a cell-mediated Th1 type response to a humoral Th2 response with the progression of disease from a subclinical to clin...

  9. ZAP-70, CTLA-4, and proximal T cell receptor signaling in cows infected with Mycobacterium avium subsp. paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Paratuberculosis is a chronic intestinal disease of ruminant animals caused by Mycobacterium avium subsp. paratuberculosis (MAP). A hallmark of paratuberculosis is a transition from a cell-mediated Th1 type response to a humoral Th2 response with the progression of disease from a subclinical to clin...

  10. NlpC/P60 domain-containing proteins of Mycobacterium avium subspecies paratuberculosis that differentially bind and hydrolyze peptidoglycan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While intense research is being conducted to develop faster and more reliable methods for diagnosis of Johne’s disease, there are still significant knowledge gaps concerning the molecular function of Mycobacterium avium subspecies paratuberculosis proteins. Therefore, we describe atomic resolution ...

  11. Isolated Endobronchial Mycobacterium avium Disease Associated with Lobar Atelectasis in an Immunocompetent Young Adult: A Case Report and Literature Review.

    PubMed

    Kim, Hye In; Kim, Ji Won; Kim, Jun Young; Kim, Young Nam; Kim, Jin Hae; Jeong, Byeong-Ho; Chung, Myung Jin; Koh, Won-Jung

    2015-10-01

    The prevalence of lung diseases caused by nontuberculous mycobacteria (NTM) is increasing worldwide. Unlike pulmonary tuberculosis, endobronchial NTM diseases are very rare with the majority of cases reported in patients with human immunodeficiency virus infection and acquired immune deficiency syndrome. We reported a rare case of endobronchial Mycobacterium avium disease associated with lobar atelectasis in a young immunocompetent patient and reviewed the relevant iterature.

  12. Prevention of Mycobacterium avium subsp. paratuberculosis (MAP) Infection in Balb/c Mice by Feeding Probiotic Lactobacillus acidophilus NP-51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to examine effects of feeding Lactobacillus acidophilus strain NP51 to mice challenged with Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne’s disease. We hypothesized that feeding NP51 would increase Th-1 responses and decrease prog...

  13. Prevention of Mycobacterium avium subsp. paratuberculosis (MAP) infection in BALB/c mice by feeding probiotic Lactobacillus acidophilus NP-51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to examine effects of feeding Lactobacillus acidophilus strain NP51 to mice challenged with Mycobacterium avium subspecies paratuberculosis (MAP). Mice were randomized to ten treatment groups; sentinels, control, heat-killed MAP, viable MAP, heat-killed NP51, viable ...

  14. Prevention of Mycobacterium avium subsp. paratuberculosis (MAP) infection in Balb/c mice by feeding probiotic Lactobacillus acidophilus NP-51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to examine effects of feeding Lactobacillus acidophilus strain NP51 to mice challenged with Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne’s disease. We hypothesized that feeding NP51 would increase Th-1 responses and decrease prog...

  15. Prevention of Mycobacterium avium subsp. paratuberculosis (MAP) Infection in BALB/c Mice by Feeding Probiotic Lactobacillus acidophilus NP-51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to examine effects of feeding Lactobacillus acidophilus strain NP51 to mice challenged with Mycobacterium avium subspecies paratuberculosis (MAP). Mice were randomized to ten treatment groups; sentinels, control, heat-killed MAP, viable MAP, heat-killed NP51, viable ...

  16. Mediation of host immune responses after immunization of neonatal calves with a heat-killed Mycobacterium avium subsp. paratuberculosis vaccine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major drawback of current whole-cell vaccines for Mycobacterium avium subsp. paratuberculosis(MAP) is the interference with diagnostic tests for bovine tuberculosis and paratuberculosis. The current study was designed to explore effects of immunization with a heat-killed whole cell vaccine (Mycop...

  17. Differences in intermittent and continuous fecal shedding patterns between natural and experimental Mycobacterium avium subspecies paratuberculosis infections in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this paper is to study shedding patterns of cows infected with Mycobacterium avium subsp. paratuberculosis (MAP). While multiple single farm studies of MAP dynamics were reported, there is not large-scale meta-analysis of both natural and experimental infections. Large difference...

  18. Gamma-delta T cell responses in subclinical and clinical stages of Bovine Mycobacterium Avium Paratuberculosis infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The early immune response to Mycobacterium avium subsp. paratuberculosis (MAP) in cattle is characterized by a Th1-like immune response effective in controlling bacterial proliferation during the subclinical stage of infection. In young calves nearly 60% of circulating lymphocytes are gamma delta T ...

  19. The effects of progressing and nonprogressing Mycobacterium avium ssp. paratuberculosis infection on milk production in dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Longitudinal data from three commercial dairy herds in the northeast United States, collected from 2004 to 2011, were analyzed to determine the effect of Johne’s disease status and path on milk production. Disease status, as indicated by Mycobacterium avium subsp. paratuberculosis test results, was ...

  20. Prevention of Mycobacterium avium subsp. paratuberculosis Infection in BALB/c Mice by Feeding Lactobacillus acidophilus Strain NP-51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The immune responses of 390 BALB/c mice fed the probiotic Lactobacillus acidophilus strain NP51® and infected with Mycobacterium avium subspecies paratuberculosis (MAP) were evaluated in a 6-month trial. Mice were randomized to nine treatment groups fed either viable- or heat-killed NP51 and inocula...

  1. Longitudinal data collection of Mycobacterium avium subspecies Paratuberculosis infections in dairy herds. Collection and use of observational data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Longitudinal infection data on Mycobacterium avium subspecies paratuberculosis (MAP) was collected on three dairy farms in Northeastern United States during approximately 10 years. Precise data on animal characteristics and animal location within farm were collected on these farms. Cows were followe...

  2. How does a Mycobacterium change its spots? Applying molecular tools to track diverse strains of Mycobacterium avium subspecies paratuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Defining genetic diversity in the wake of the release of several Mycobacterium avium subsp. paratuberculosis (MAP) genome sequences has become a major emphasis in the molecular biology and epidemiology of Johne’s disease research. These data can now be used to define the extent of strain diversity ...

  3. Identification of Mycobacterium avium subsp. paratuberculosis in Biopsy Specimens from Patients with Crohn's Disease Identified by In Situ Hybridization

    PubMed Central

    Sechi, Leonardo A.; Manuela, Mura; Francesco, Tanda; Amelia, Lissia; Antonello, Solinas; Giovanni, Fadda; Stefania, Zanetti

    2001-01-01

    Crohn's disease is a chronic inflammatory disease of the gastrointestinal tract of unknown etiology. We report on the presence of cell wall-deficient Mycobacterium avium subsp. paratuberculosis in 35 of 48 paraffin-embedded tissue specimens from 33 patients with Crohn's disease by in situ hybridization with IS900 as a probe. PMID:11724871

  4. Comparison of fecal DNA extraction kits for the detection of Mycobacterium avium subsp. paratuberculosis by polymerase chain reaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culture of Mycobacterium avium subsp. paratuberculosis (MAP) from feces has been considered the gold standard for the diagnosis of paratuberculosis for many years. However, direct fecal PCR is becoming more widely used today, demonstrating similar sensitivity and specificity to culture. To ensure ef...

  5. Persistence of Mycobacterium avium subsp. paratuberculosis in soil, crops, and ensiled feed following manure spreading on infected dairy farms

    PubMed Central

    Fecteau, Marie-Eve; Hovingh, Ernest; Whitlock, Robert H.; Sweeney, Raymond W.

    2013-01-01

    The goal of this study was to determine the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil, crops, and ensiled feeds following manure spreading. This bacterium was often found in soil samples, but less frequently in harvested feeds and silage. Spreading of manure on fields used for crop harvest is preferred to spreading on grazing pastures. PMID:24179246

  6. Cortex and memory: emergence of a new paradigm.

    PubMed

    Fuster, Joaquín M

    2009-11-01

    Converging evidence from humans and nonhuman primates is obliging us to abandon conventional models in favor of a radically different, distributed-network paradigm of cortical memory. Central to the new paradigm is the concept of memory network or cognit--that is, a memory or an item of knowledge defined by a pattern of connections between neuron populations associated by experience. Cognits are hierarchically organized in terms of semantic abstraction and complexity. Complex cognits link neurons in noncontiguous cortical areas of prefrontal and posterior association cortex. Cognits overlap and interconnect profusely, even across hierarchical levels (heterarchically), whereby a neuron can be part of many memory networks and thus many memories or items of knowledge.

  7. Rapid assessment of the viability of Mycobacterium avium subsp. paratuberculosis cells after heat treatment, using an optimized phage amplification assay.

    PubMed

    Foddai, Antonio; Elliott, Christopher T; Grant, Irene R

    2010-03-01

    Thermal inactivation experiments were carried out to assess the utility of a recently optimized phage amplification assay to accurately enumerate viable Mycobacterium avium subsp. paratuberculosis cells in milk. Ultra-heat-treated (UHT) whole milk was spiked with large numbers of M. avium subsp. paratuberculosis organisms (10(6) to 10(7) CFU/ml) and dispensed in 100-microl aliquots in thin-walled 200-microl PCR tubes. A Primus 96 advanced thermal cycler (Peqlab, Erlangen, Germany) was used to achieve the following time and temperature treatments: (i) 63 degrees C for 3, 6, and 9 min; (ii) 68 degrees C for 20, 40, and 60 s; and (iii) 72 degrees C for 5, 10, 15, and 25 s. After thermal stress, the number of surviving M. avium subsp. paratuberculosis cells was assessed by both phage amplification assay and culture on Herrold's egg yolk medium (HEYM). A high correlation between PFU/ml and CFU/ml counts was observed for both unheated (r(2) = 0.943) and heated (r(2) = 0.971) M. avium subsp. paratuberculosis cells. D and z values obtained using the two types of counts were not significantly different (P > 0.05). The D(68 degrees C), mean D(63 degrees C), and D(72 degrees C) for four M. avium subsp. paratuberculosis strains were 81.8, 9.8, and 4.2 s, respectively, yielding a mean z value of 6.9 degrees C. Complete inactivation of 10(6) to 10(7) CFU of M. avium subsp. paratuberculosis/ml milk was not observed for any of the time-temperature combinations studied; 5.2- to 6.6-log(10) reductions in numbers were achieved depending on the temperature and time. Nonlinear thermal inactivation kinetics were consistently observed for this bacterium. This study confirms that the optimized phage assay can be employed in place of conventional culture on HEYM to speed up the acquisition of results (48 h instead of a minimum of 6 weeks) for inactivation experiments involving M. avium subsp. paratuberculosis-spiked samples.

  8. Mycobacterium avium subsp. hominissuis Infection in Swine Associated with Peat Used for Bedding

    PubMed Central

    Johansen, Tone Bjordal; Lium, Bjørn; Jørgensen, Anne; Djønne, Berit

    2014-01-01

    Mycobacterium avium subsp. hominissuis is an environmental bacterium causing opportunistic infections in swine, resulting in economic losses. Additionally, the zoonotic aspect of such infections is of concern. In the southeastern region of Norway in 2009 and 2010, an increase in condemnation of pig carcasses with tuberculous lesions was seen at the meat inspection. The use of peat as bedding in the herds was suspected to be a common factor, and a project examining pigs and environmental samples from the herds was initiated. Lesions detected at meat inspection in pigs originating from 15 herds were sampled. Environmental samples including peat from six of the herds and from three peat production facilities were additionally collected. Samples were analysed by culture and isolates genotyped by MLVA analysis. Mycobacterium avium subsp. hominissuis was detected in 35 out of 46 pigs, in 16 out of 20 samples of peat, and in one sample of sawdust. MLVA analysis demonstrated identical isolates from peat and pigs within the same farms. Polyclonal infection was demonstrated by analysis of multiple isolates from the same pig. To conclude, the increase in condemnation of porcine carcasses at slaughter due to mycobacteriosis seemed to be related to untreated peat used as bedding. PMID:25431762

  9. Antibody recognition to secreted proteins of Mycobacterium avium subsp. paratuberculosis in sera from infected ruminants.

    PubMed

    Pradenas, M; Jara, M C; Hernández, N; Zambrano, A; Collins, M T; Kruze, J

    2009-09-18

    Two liquid culture media to obtain secreted proteins of Mycobacterium avium subsp. paratuberculosis at different incubation periods were evaluated. Middlebrook 7H9-OADC (7H9) and Watson-Reid (WR) broths were inoculated with a field strain of M. paratuberculosis and growth curves determined using nonlinear regression analysis. Most culture filtrate (CF) proteins were of low molecular weight and reacted strongly against sera from cultured-positive cases of paratuberculosis. CF proteins obtained in WR yielded a higher number of bands and were detected earlier than those obtained from 7H9. A high degree of variability in CF protein immunoreactivity was seen among infected animals. Sera from cattle with clinical paratuberculosis or heavy fecal shedders of M. paratuberculosis reacted more intensively and to more CF proteins than did sera from other infected cattle. Immunoblots showed differences in antibody binding to CF proteins when sera were absorbed with M. avium but not with others environmental mycobacteria. Immunoblots with sera from infected goats and a sheep showed reactivity with proteins of 32, 33 and 46kDa both before and after the sera were absorbed with M. phlei. Antibodies found in serum of infected deer reacted with CF proteins in a similar way as did for cattle. These results suggest that a pool of CF proteins of M. paratuberculosis could be good candidates as antigens for serodiagnosis of paratuberculosis.

  10. Environmental Survival of Mycobacterium avium subsp. paratuberculosis in Different Climatic Zones of Eastern Australia

    PubMed Central

    Begg, Douglas J.; Dhand, Navneet K.; Watt, Bruce; Whittington, Richard J.

    2014-01-01

    The duration of survival of both the S and C strains of Mycobacterium avium subsp. paratuberculosis in feces was quantified in contrasting climatic zones of New South Wales, Australia, and detailed environmental temperature data were collected. Known concentrations of S and C strains in feces placed on soil in polystyrene boxes were exposed to the environment with or without the provision of shade (70%) at Bathurst, Armidale, Condobolin, and Broken Hill, and subsamples taken every 2 weeks were cultured for the presence of M. avium subsp. paratuberculosis. The duration of survival ranged from a minimum of 1 week to a maximum of 16 weeks, and the provision of 70% shade was the most important factor in extending the survival time. The hazard of death for exposed compared to shaded samples was 20 and 9 times higher for the S and C strains, respectively. Site did not affect the survival of the C strain, but for the S strain, the hazard of death was 2.3 times higher at the two arid zone sites (Broken Hill and Condobolin) than at the two temperate zone sites (Bathurst and Armidale). Temperature measurements revealed maximum temperatures exceeding 60°C and large daily temperature ranges at the soil surface, particularly in exposed boxes. PMID:24463974

  11. Therapeutic efficacy of liposomal rifabutin in a Mycobacterium avium model of infection.

    PubMed

    Gaspar, M M; Neves, S; Portaels, F; Pedrosa, J; Silva, M T; Cruz, M E

    2000-09-01

    Liposomal formulations of rifabutin were developed, and the effects of some parameters on the incorporation efficiency were studied. The antimycobacterial activity of rifabutin incorporated into liposomes prepared with phosphatidylcholine and phosphatidylserine (molar ratio, 7:3) was evaluated in a murine model of infection with a virulent Mycobacterium avium strain (strain P1581) and was compared with that of free rifabutin. The influences of the size of the liposomal rifabutin formulation, the administered doses, and the treatment schedules on the evolution of infection were studied. Two types of treatment schedules were assayed: therapeutic and prophylactic. The therapeutic treatment started 2 weeks after infection, while the prophylactic treatment began 1 day before the experimental infection with mycobacteria. Incorporation of rifabutin in liposomes resulted in a significant enhancement of activity against M. avium infection compared to that of rifabutin in the free form in both schedules. These results demonstrate that liposomal formulations of antibiotics such as rifabutin may be effective for the treatment or prophylaxis of infectious diseases.

  12. Therapeutic Efficacy of Liposomal Rifabutin in a Mycobacterium avium Model of Infection

    PubMed Central

    Gaspar, Maria Manuela; Neves, Susana; Portaels, Françoise; Pedrosa, Jorge; Silva, Manuel T.; Cruz, Maria Eugénia M.

    2000-01-01

    Liposomal formulations of rifabutin were developed, and the effects of some parameters on the incorporation efficiency were studied. The antimycobacterial activity of rifabutin incorporated into liposomes prepared with phosphatidylcholine and phosphatidylserine (molar ratio, 7:3) was evaluated in a murine model of infection with a virulent Mycobacterium avium strain (strain P1581) and was compared with that of free rifabutin. The influences of the size of the liposomal rifabutin formulation, the administered doses, and the treatment schedules on the evolution of infection were studied. Two types of treatment schedules were assayed: therapeutic and prophylactic. The therapeutic treatment started 2 weeks after infection, while the prophylactic treatment began 1 day before the experimental infection with mycobacteria. Incorporation of rifabutin in liposomes resulted in a significant enhancement of activity against M. avium infection compared to that of rifabutin in the free form in both schedules. These results demonstrate that liposomal formulations of antibiotics such as rifabutin may be effective for the treatment or prophylaxis of infectious diseases. PMID:10952590

  13. Characterization of activity and expression of isocitrate lyase in Mycobacterium avium and Mycobacterium tuberculosis.

    PubMed

    Höner Zu Bentrup, K; Miczak, A; Swenson, D L; Russell, D G

    1999-12-01

    Analysis by two-dimensional gel electrophoresis revealed that Mycobacterium avium expresses several proteins unique to an intracellular infection. One abundant protein with an apparent molecular mass of 50 kDa was isolated, and the N-terminal sequence was determined. It matches a sequence in the M. tuberculosis database (Sanger) with similarity to the enzyme isocitrate lyase of both Corynebacterium glutamicum and Rhodococcus fascians. Only marginal similarity was observed between this open reading frame (ORF) (termed icl) and a second distinct ORF (named aceA) which exhibits a low similarity to other isocitrate lyases. Both ORFs can be found as distinct genes in the various mycobacterial databases recently published. Isocitrate lyase is a key enzyme in the glyoxylate cycle and is essential as an anapleurotic enzyme for growth on acetate and certain fatty acids as carbon source. In this study we express and purify Icl, as well as AceA proteins, and show that both exhibit isocitrate lyase activity. Various known inhibitors for isocitrate lyase were effective. Furthermore, we present evidence that in both M. avium and M. tuberculosis the production and activity of the isocitrate lyase is enhanced under minimal growth conditions when supplemented with acetate or palmitate.

  14. Hyperhydricity of Prunus avium shoots cultured on gelrite: a controlled stress response.

    PubMed

    Franck, Thierry; Kevers, Claire; Gaspar, Thomas; Dommes, Jacques; Deby, Carol; Greimers, Roland; Serteyn, Didier; Deby-Dupont, Ginette

    2004-06-01

    Hyperhydricity is a physiological disorder frequently affecting shoots vegetatively propagated in vitro. Hyperhydric shoots are characterised by a translucent aspect due to a chlorophyll deficiency, a not very developed cell wall and a high water content. Hyperhydricity of Prunus avium shoots was expressed in vitro in one multiplication cycle by replacing the gelling agent agar (normal shoots: NS) by gelrite (hyperhydric shoots: HS). P. avium shoots evolving towards the hyperhydric state produced higher amounts of ethylene, polyamines (PAs) and proline, which are substances considered as stress markers. A higher activity of glutathione peroxidase (GPX; EC 1.11.1.9), involved in organic hydroperoxide elimination, suggested an increased production of these compounds in HS. The unchanged free fatty acid composition indicated no HS membrane damages compared to NS. The ploidy level of HS nuclei was not affected, but the bigger size and the lower percentage of nuclei during the S phase suggested a slowing down of the cell cycle. The results argued for a stress response of the HS, but no signs of oxidative damages of lipid membrane and nucleus were observed. The discussion points out paradoxical results in a classical analysis of stress and suggests an alternative way of defense mechanisms in HS, involving homeostatic regulation and controlled degradation processes to maintain integrity and vital functions of the cell.

  15. A photoelectrocatalytic process that disinfects water contaminated with Mycobacterium kansasii and Mycobacterium avium.

    PubMed

    Brugnera, Michelle Fernanda; Miyata, Marcelo; Zocolo, Guilherme Julião; Leite, Clarice Queico Fujimura; Zanoni, Maria Valnice Boldrin

    2013-11-01

    Nontuberculous mycobacteria are resistant to conventional water treatment; indeed, they have been recovered from a wide variety of environmental sources. Here, we applied the photoelectrocatalytic technique using a Ti/TiO2-Ag photoanode to inactivate mycobacteria. For a mycobacteria population of 5 × 10(8) CFU mL(-1), we achieved 99.9 and 99.8% inactivation of Mycobacterium kansasii and Mycobacterium avium with rate constant of 6.2 × 10(-3) and 4.2 × 10(-3) min(-1), respectively, after 240 min. We compared the proposed method with the photolytic and photocatalytic methods. Using a mycobacteria population of 7.5 × 10(4) CFU mL(-1), the proposed Ti/TiO2-Ag photoanode elicited total mycobacteria inactivation within 3 min of treatment; the presence of Ag nanoparticles in the electrode provided 1.5 larger degradation rate constant as compared with the Ti/TiO2 anode (1.75 × 10(-2) for M. kansassi and 1.98 × 10(-2) for M. avium). We monitored the degradation of the metabolites released during cellular lysis by TOC removal, sugar release, chromatography, and mass spectrometry measurements; photoelectrocatalysis and Ti/TiO2-Ag photoanodes furnished the best results.

  16. Mycobacterium avium Subspecies paratuberculosis Recombinant Proteins Modulate Antimycobacterial Functions of Bovine Macrophages.

    PubMed

    Bannantine, John P; Stabel, Judith R; Laws, Elizabeth; D Cardieri, Maria Clara; Souza, Cleverson D

    2015-01-01

    It has been shown that Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) activates the Mitogen Activated Protein Kinase (MAPK) p38 pathway, yet it is unclear which components of M. paratuberculosis are involved in the process. Therefore, a set of 42 M. paratuberculosis recombinant proteins expressed from coding sequences annotated as lipoproteins were screened for their ability to induce IL-10 expression, an indicator of MAPKp38 activation, in bovine monocyte-derived macrophages. A recombinant lipoprotein, designated as MAP3837c, was among a group of 6 proteins that strongly induced IL-10 gene transcription in bovine macrophages, averaging a 3.1-fold increase compared to non-stimulated macrophages. However, a parallel increase in expression of IL-12 and TNF-α was only observed in macrophages exposed to a subset of these 6 proteins. Selected recombinant proteins were further analyzed for their ability to enhance survival of M. avium within bovine macrophages as measured by recovered viable bacteria and nitrite production. All 6 IL-10 inducing MAP recombinant proteins along with M. paratuberculosis cells significantly enhanced phosphorylation of MAPK-p38 in bovine macrophages. Although these proteins are likely not post translationally lipidated in E. coli and thus is a limitation in this study, these results form the foundation of how the protein component of the lipoprotein interacts with the immune system. Collectively, these data reveal M. paratuberculosis proteins that might play a role in MAPK-p38 pathway activation and hence in survival of this organism within bovine macrophages.

  17. Mycobacterium avium subsp. hominissuis infection in swine associated with peat used for bedding.

    PubMed

    Johansen, Tone Bjordal; Agdestein, Angelika; Lium, Bjørn; Jørgensen, Anne; Djønne, Berit

    2014-01-01

    Mycobacterium avium subsp. hominissuis is an environmental bacterium causing opportunistic infections in swine, resulting in economic losses. Additionally, the zoonotic aspect of such infections is of concern. In the southeastern region of Norway in 2009 and 2010, an increase in condemnation of pig carcasses with tuberculous lesions was seen at the meat inspection. The use of peat as bedding in the herds was suspected to be a common factor, and a project examining pigs and environmental samples from the herds was initiated. Lesions detected at meat inspection in pigs originating from 15 herds were sampled. Environmental samples including peat from six of the herds and from three peat production facilities were additionally collected. Samples were analysed by culture and isolates genotyped by MLVA analysis. Mycobacterium avium subsp. hominissuis was detected in 35 out of 46 pigs, in 16 out of 20 samples of peat, and in one sample of sawdust. MLVA analysis demonstrated identical isolates from peat and pigs within the same farms. Polyclonal infection was demonstrated by analysis of multiple isolates from the same pig. To conclude, the increase in condemnation of porcine carcasses at slaughter due to mycobacteriosis seemed to be related to untreated peat used as bedding.

  18. Coexistent Pseudogout and Mycobacterium avium-intracellulare Septic Arthritis in a Patient with HIV and ESRD

    PubMed Central

    Wali, Omer M.; Cervellione, Kelly L.; Singh, Bhupinder B.; Bagheri, Farshad

    2016-01-01

    Pseudogout is a crystal-induced arthropathy characterized by the deposition of calcium pyrophosphate dihydrate (CPPD) crystals in synovial fluid, menisci, or articular cartilage. Although not very common, this entity can be seen in patients with chronic kidney disease (CKD). Septic arthritis due to Mycobacterium avium-intracellulare (MAI) is a rare entity that can affect immunocompromised patients such as those with acquired immunodeficiency syndrome (AIDS) or those who are on immunosuppressive drugs. Here, we describe a 51-year-old female who presented with fever, right knee pain, swelling, warmth, and decreased range of motion for several days. The initial assessment was consistent with pseudogout, with negative bacterial and fungal cultures. However, due to high white blood cell (WBC) count in the synovial fluid analysis, she was empirically started on intravenous (IV) vancomycin and piperacillin-tazobactam and discharged on IV vancomycin and cefepime, while acid-fast bacilli (AFB) culture was still in process. Seventeen days later, AFB culture grew Mycobacterium avium-intracellulare (MAI), and she was readmitted for relevant management. This case illustrates that septic arthritis due to MAI should be considered in the differential diagnosis of septic arthritis in immunocompromised patients. PMID:27803833

  19. Mycobacterium avium subspecies hominissuis disseminated infection in a Basset Hound dog.

    PubMed

    Campora, Luca; Corazza, Michele; Zullino, Cristina; Ebani, Valentina V; Abramo, Francesca

    2011-09-01

    In the current report, a case in Italy of disseminated Mycobacterium avium subsp. hominissuis infection in a dog from an American lineage of Basset Hounds is described. A 2-year-old intact female Basset Hound presented with persistent lymphadenopathy, lameness, and a history characterized by coccidiosis, bacterial gastroenteritis, and alopecia. Lymphadenitis, with macrophages containing a few intracytoplasmic, negative staining, Ziehl-Neelsen-positive bacilli, was detected by a popliteal fine-needle aspirate leading to the diagnosis of mycobacteriosis. Ultrasound and X-ray examinations revealed visceral and mediastinal lymphadenopathy. Because of the extent of the disease, the dog was humanely euthanized. Significant gross abnormalities, such as enlargement of the cranial mediastinal lymph nodes with encapsulated areas of caseous necrosis and generalized lymphadenopathy, were observed at necropsy. Granulomatous lesions were histopathologically detected in the liver and spleen. Ziehl-Neelsen-positive bacilli were observed in all examined lymph node, liver, spleen, lung, and bone marrow smears. Lymph nodes and liver were collected in order to pursue speciation by bacterial culture and molecular biology; multiplex polymerase chain reaction results classified the pathogen as M. avium subsp. hominissuis. Although an immune system deficiency was not investigated, anamnesis suggests that the dog was immunocompromised. Furthermore, the dog came from an American stock of Basset Hound, and for some of this breed, a predisposition to this infection has been hypothesized.

  20. Turbomachinery computational fluid dynamics: asymptotes and paradigm shifts.

    PubMed

    Dawes, W N

    2007-10-15

    This paper reviews the development of computational fluid dynamics (CFD) specifically for turbomachinery simulations and with a particular focus on application to problems with complex geometry. The review is structured by considering this development as a series of paradigm shifts, followed by asymptotes. The original S1-S2 blade-blade-throughflow model is briefly described, followed by the development of two-dimensional then three-dimensional blade-blade analysis. This in turn evolved from inviscid to viscous analysis and then from steady to unsteady flow simulations. This development trajectory led over a surprisingly small number of years to an accepted approach-a 'CFD orthodoxy'. A very important current area of intense interest and activity in turbomachinery simulation is in accounting for real geometry effects, not just in the secondary air and turbine cooling systems but also associated with the primary path. The requirements here are threefold: capturing and representing these geometries in a computer model; making rapid design changes to these complex geometries; and managing the very large associated computational models on PC clusters. Accordingly, the challenges in the application of the current CFD orthodoxy to complex geometries are described in some detail. The main aim of this paper is to argue that the current CFD orthodoxy is on a new asymptote and is not in fact suited for application to complex geometries and that a paradigm shift must be sought. In particular, the new paradigm must be geometry centric and inherently parallel without serial bottlenecks. The main contribution of this paper is to describe such a potential paradigm shift, inspired by the animation industry, based on a fundamental shift in perspective from explicit to implicit geometry and then illustrate this with a number of applications to turbomachinery.

  1. Testing paradigms of ecosystem change under climate warming in Antarctica.

    PubMed

    Melbourne-Thomas, Jessica; Constable, Andrew; Wotherspoon, Simon; Raymond, Ben

    2013-01-01

    Antarctic marine ecosystems have undergone significant changes as a result of human activities in the past and are now responding in varied and often complicated ways to climate change impacts. Recent years have seen the emergence of large-scale mechanistic explanations-or "paradigms of change"-that attempt to synthesize our understanding of past and current changes. In many cases, these paradigms are based on observations that are spatially and temporally patchy. The West Antarctic Peninsula (WAP), one of Earth's most rapidly changing regions, has been an area of particular research focus. A recently proposed mechanistic explanation for observed changes in the WAP region relates changes in penguin populations to variability in krill biomass and regional warming. While this scheme is attractive for its simplicity and chronology, it may not account for complex spatio-temporal processes that drive ecosystem dynamics in the region. It might also be difficult to apply to other Antarctic regions that are experiencing some, though not all, of the changes documented for the WAP. We use qualitative network models of differing levels of complexity to test paradigms of change for the WAP ecosystem. Importantly, our approach captures the emergent effects of feedback processes in complex ecological networks and provides a means to identify and incorporate uncertain linkages between network elements. Our findings highlight key areas of uncertainty in the drivers of documented trends, and suggest that a greater level of model complexity is needed in devising explanations for ecosystem change in the Southern Ocean. We suggest that our network approach to evaluating a recent and widely cited paradigm of change for the Antarctic region could be broadly applied in hypothesis testing for other regions and research fields.

  2. Testing Paradigms of Ecosystem Change under Climate Warming in Antarctica

    PubMed Central

    Melbourne-Thomas, Jessica; Constable, Andrew; Wotherspoon, Simon; Raymond, Ben

    2013-01-01

    Antarctic marine ecosystems have undergone significant changes as a result of human activities in the past and are now responding in varied and often complicated ways to climate change impacts. Recent years have seen the emergence of large-scale mechanistic explanations–or “paradigms of change”–that attempt to synthesize our understanding of past and current changes. In many cases, these paradigms are based on observations that are spatially and temporally patchy. The West Antarctic Peninsula (WAP), one of Earth’s most rapidly changing regions, has been an area of particular research focus. A recently proposed mechanistic explanation for observed changes in the WAP region relates changes in penguin populations to variability in krill biomass and regional warming. While this scheme is attractive for its simplicity and chronology, it may not account for complex spatio-temporal processes that drive ecosystem dynamics in the region. It might also be difficult to apply to other Antarctic regions that are experiencing some, though not all, of the changes documented for the WAP. We use qualitative network models of differing levels of complexity to test paradigms of change for the WAP ecosystem. Importantly, our approach captures the emergent effects of feedback processes in complex ecological networks and provides a means to identify and incorporate uncertain linkages between network elements. Our findings highlight key areas of uncertainty in the drivers of documented trends, and suggest that a greater level of model complexity is needed in devising explanations for ecosystem change in the Southern Ocean. We suggest that our network approach to evaluating a recent and widely cited paradigm of change for the Antarctic region could be broadly applied in hypothesis testing for other regions and research fields. PMID:23405116

  3. Suspicion of Mycobacterium avium subsp. paratuberculosis Transmission between Cattle and Wild-Living Red Deer (Cervus elaphus) by Multitarget Genotyping

    PubMed Central

    Fritsch, Isabel; Luyven, Gabriele; Köhler, Heike; Lutz, Walburga

    2012-01-01

    Multitarget genotyping of the etiologic agent Mycobacterium avium subsp. paratuberculosis is necessary for epidemiological tracing of paratuberculosis (Johne's disease). The study was undertaken to assess the informative value of different typing techniques and individual genome markers by investigation of M. avium subsp. paratuberculosis transmission between wild-living red deer and farmed cattle with known shared habitats. Fifty-three M. avium subsp. paratuberculosis type II isolates were differentiated by short sequence repeat analysis (SSR; 4 loci), mycobacterial interspersed repetitive-unit–variable-number tandem-repeat analysis (MIRU-VNTR; 8 loci), and restriction fragment length polymorphism analysis based on IS900 (IS900-RFLP) using BstEII and PstI digestion. Isolates originated from free-living red deer (Cervus elaphus) from Eifel National Park (n = 13), six cattle herds living in the area of this park (n = 23), and five cattle herds without any contact with these red deer (n = 17). Data based on individual herds and genotypes verified that SSR G2 repeats did not exhibit sufficient stability for epidemiological studies. Two common SSR profiles (without G2 repeats), nine MIRU-VNTR patterns, and nine IS900-RFLP patterns were detected, resulting in 17 genotypes when combined. A high genetic variability was found for red deer and cattle isolates within and outside Eifel National Park, but it was revealed only by combination of different typing techniques. Results imply that within this restricted area, wild-living and farmed animals maintain a reservoir for specific M. avium subsp. paratuberculosis genotypes. No host relation of genotypes was obtained. Results suggested that four genotypes had been transmitted between and within species and that one genotype had been transmitted between cattle herds only. Use of multitarget genotyping for M. avium subsp. paratuberculosis type II strains and sufficiently stable genetic markers is essential for reliable

  4. Biofabrication: a 21st century manufacturing paradigm.

    PubMed

    Mironov, V; Trusk, T; Kasyanov, V; Little, S; Swaja, R; Markwald, R

    2009-06-01

    Biofabrication can be defined as the production of complex living and non-living biological products from raw materials such as living cells, molecules, extracellular matrices, and biomaterials. Cell and developmental biology, biomaterials science, and mechanical engineering are the main disciplines contributing to the emergence of biofabrication technology. The industrial potential of biofabrication technology is far beyond the traditional medically oriented tissue engineering and organ printing and, in the short term, it is essential for developing potentially highly predictive human cell- and tissue-based technologies for drug discovery, drug toxicity, environmental toxicology assays, and complex in vitro models of human development and diseases. In the long term, biofabrication can also contribute to the development of novel biotechnologies for sustainable energy production in the future biofuel industry and dramatically transform traditional animal-based agriculture by inventing 'animal-free' food, leather, and fur products. Thus, the broad spectrum of potential applications and rapidly growing arsenal of biofabrication methods strongly suggests that biofabrication can become a dominant technological platform and new paradigm for 21st century manufacturing. The main objectives of this review are defining biofabrication, outlining the most essential disciplines critical for emergence of this field, analysis of the evolving arsenal of biofabrication technologies and their potential practical applications, as well as a discussion of the common challenges being faced by biofabrication technologies, and the necessary conditions for the development of a global biofabrication research community and commercially successful biofabrication industry.

  5. Production and Evaluation of an Improved Mycobacterium avium subsp. paratuberculosis Purified Protein Derivative for Use in In-Vivo and In-Vitro Diagnostic Testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purified protein derivatives (PPD’s) were prepared from the cultured filtrate of Mycobacterium avium subsp. paratuberculosis (MAP) ATCC strain 19698. Production of PPD has historically been problematic for maintaining optimal floating cultures yielding defined immunogenic components. To obtain mor...

  6. Treatment with antibiotics is detrimental to the recovery of viable Mycobacterium avium subsp. paratuberculosis cultured from milk and colostrum of dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic cocktails are frequently used as secondary decontaminants prior to the culture of Mycobacterium avium subsp. paratuberculosis (MAP). This study investigated whether secondary incubation with an antibiotic cocktail containing vancomycin, nalidixic acid, and amphotericin B after primary exp...

  7. Effect of Feeding Heat-Treated Colostrum on Preweaning Health, Economics and Transmission of Mycobacterium avium subsp. paratuberculosis in Dairy Calves: Phase I

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction and Objectives Colostrum provides protective immunoglobulins (Ig) and nutrients essential for calf health and performance. However, colostrum may also represent an early source of pathogen exposure including Mycobacterium avium subsp. paratuberculosis (MAP). Pilot studies have suggest...

  8. Think globally, research locally: paradigms and place in agroecological research.

    PubMed

    Reynolds, Heather L; Smith, Alex A; Farmer, James R

    2014-10-01

    Conducting science for practical ends implicates scientists, whether they wish it or not, as agents in social-ecological systems, raising ethical, economic, environmental, and political issues. Considering these issues helps scientists to increase the relevance and sustainability of research outcomes. As we rise to the worthy call to connect basic research with food production, scientists have the opportunity to evaluate alternative food production paradigms and consider how our research funds and efforts are best employed. In this contribution, we review some of the problems produced by science conducted in service of industrial agriculture and its associated economic growth paradigm. We discuss whether the new concept of "ecological intensification" can rescue the industrial agriculture/growth paradigm and present an emerging alternative paradigm of decentralized, localized, biodiversity-promoting agriculture for a steady-state economy. This "custom fit" agriculture engages constructively with complex and highly localized ecosystems, and we draw from examples of published work to demonstrate how ecologists can contribute by using approaches that acknowledge local agricultural practices and draw on community participation.

  9. Forensic voice comparison and the paradigm shift.

    PubMed

    Morrison, Geoffrey Stewart

    2009-12-01

    We are in the midst of a paradigm shift in the forensic comparison sciences. The new paradigm can be characterised as quantitative data-based implementation of the likelihood-ratio framework with quantitative evaluation of the reliability of results. The new paradigm was widely adopted for DNA profile comparison in the 1990s, and is gradually spreading to other branches of forensic science, including forensic voice comparison. The present paper first describes the new paradigm, then describes the history of its adoption for forensic voice comparison over approximately the last decade. The paradigm shift is incomplete and those working in the new paradigm still represent a minority within the forensic-voice-comparison community.

  10. Prosthetic Joint Infection due to Mycobacterium avium-intracellulare in a Patient with Rheumatoid Arthritis: A Case Report and Review of the Literature

    PubMed Central

    Schneider, Brenton; Alpern, Jonathan D.

    2017-01-01

    Nontuberculous mycobacteria (NTM) are a rare cause of prosthetic joint infections (PJI). However, the prevalence of NTM infections may be increasing with the rise of newer immunosuppressive medications such as biologics. In this case report, we describe a rare complication of immunosuppressive therapies and highlight the complexity of diagnosing and treating PJI due to NTM. The patient is a 79-year-old Caucasian male with a history of severe destructive rheumatoid arthritis on several immunosuppressive agents and right hip osteoarthritis s/p total hip arthroplasty 15 years previously with several complex revisions, presenting with several weeks of worsening right hip and abdominal pain. A right hip CT scan revealed periprosthetic fluid collections. Aspiration of three fluid pockets was AFB smear-positive and grew Mycobacterium avium-intracellulare. The patient was deemed a poor surgical candidate. He underwent a limited I&D and several months of antimycobacterial therapy but clinically deteriorated and opted for hospice care. PJI caused by NTM are rare and difficult to treat. The increased use of biologics and prosthetic joint replacements over the past several decades may increase the risk of PJI due to NTM. A high index of suspicion for NTM in immunosuppressed patients with PJI is needed. PMID:28280641

  11. Efficacy of various pasteurization time-temperature conditions in combination with homogenization on inactivation of Mycobacterium avium subsp. paratuberculosis in milk.

    PubMed

    Grant, Irene R; Williams, Alan G; Rowe, Michael T; Muir, D Donald

    2005-06-01

    The effect of various pasteurization time-temperature conditions with and without homogenization on the viability of Mycobacterium avium subsp. paratuberculosis was investigated using a pilot-scale commercial high-temperature, short-time (HTST) pasteurizer and raw milk spiked with 10(1) to 10(5) M. avium subsp. paratuberculosis cells/ml. Viable M. avium subsp. paratuberculosis was cultured from 27 (3.3%) of 816 pasteurized milk samples overall, 5 on Herrold's egg yolk medium and 22 by BACTEC culture. Therefore, in 96.7% of samples, M. avium subsp. paratuberculosis had been completely inactivated by HTST pasteurization, alone or in combination with homogenization. Heat treatments incorporating homogenization at 2,500 lb/in2, applied upstream (as a separate process) or in hold (at the start of a holding section), resulted in significantly fewer culture-positive samples than pasteurization treatments without homogenization (P < 0.001 for those in hold and P < 0.05 for those upstream). Where colony counts were obtained, the number of surviving M. avium subsp. paratuberculosis cells was estimated to be 10 to 20 CFU/150 ml, and the reduction in numbers achieved by HTST pasteurization with or without homogenization was estimated to be 4.0 to 5.2 log10. The impact of homogenization on clump size distribution in M. avium subsp. paratuberculosis broth suspensions was subsequently assessed using a Mastersizer X spectrometer. These experiments demonstrated that large clumps of M. avium subsp. paratuberculosis cells were reduced to single-cell or "miniclump" status by homogenization at 2,500 lb/in2. Consequently, when HTST pasteurization was being applied to homogenized milk, the M. avium subsp. paratuberculosis cells would have been present as predominantly declumped cells, which may possibly explain the greater inactivation achieved by the combination of pasteurization and homogenization.

  12. Efficacy of Various Pasteurization Time-Temperature Conditions in Combination with Homogenization on Inactivation of Mycobacterium avium subsp. paratuberculosis in Milk

    PubMed Central

    Grant, Irene R.; Williams, Alan G.; Rowe, Michael T.; Muir, D. Donald

    2005-01-01

    The effect of various pasteurization time-temperature conditions with and without homogenization on the viability of Mycobacterium avium subsp. paratuberculosis was investigated using a pilot-scale commercial high-temperature, short-time (HTST) pasteurizer and raw milk spiked with 101 to 105 M. avium subsp. paratuberculosis cells/ml. Viable M. avium subsp. paratuberculosis was cultured from 27 (3.3%) of 816 pasteurized milk samples overall, 5 on Herrold's egg yolk medium and 22 by BACTEC culture. Therefore, in 96.7% of samples, M. avium subsp. paratuberculosis had been completely inactivated by HTST pasteurization, alone or in combination with homogenization. Heat treatments incorporating homogenization at 2,500 lb/in2, applied upstream (as a separate process) or in hold (at the start of a holding section), resulted in significantly fewer culture-positive samples than pasteurization treatments without homogenization (P < 0.001 for those in hold and P < 0.05 for those upstream). Where colony counts were obtained, the number of surviving M. avium subsp. paratuberculosis cells was estimated to be 10 to 20 CFU/150 ml, and the reduction in numbers achieved by HTST pasteurization with or without homogenization was estimated to be 4.0 to 5.2 log10. The impact of homogenization on clump size distribution in M. avium subsp. paratuberculosis broth suspensions was subsequently assessed using a Mastersizer X spectrometer. These experiments demonstrated that large clumps of M. avium subsp. paratuberculosis cells were reduced to single-cell or “miniclump” status by homogenization at 2,500 lb/in2. Consequently, when HTST pasteurization was being applied to homogenized milk, the M. avium subsp. paratuberculosis cells would have been present as predominantly declumped cells, which may possibly explain the greater inactivation achieved by the combination of pasteurization and homogenization. PMID:15932977

  13. Vibrational sensitivity of the subgenual organ complex in female Sipyloidea sipylus stick insects in different experimental paradigms of stimulus direction, leg attachment, and ablation of a connective tibial sense organ.

    PubMed

    Strauß, Johannes; Lakes-Harlan, Reinhard

    2017-01-01

    We document the sensitivity to sinusoidal vibrations for chordotonal organs in the stick insect tibia (Sipyloidea sipylus). In the tibia, the scolopidial subgenual organ (~40 scolopidial sensilla), distal organ (~20 scolopidial sensilla), and distal tibial chordotonal organ (~7 scolopidial sensilla) are present. We study the sensitivity of tibial sensory organs in all leg pairs to vibration stimuli as sensory thresholds by recording summed action potentials from Nervus cruris in the femur. The tibia was stimulated with a minishaker delivering vibrational stimuli. Because different experimental procedures may affect the vibration sensitivity, we here analysed possible effects of different experimental conditions: (1) the stimulus direction delivered in either horizontal or vertical direction to the leg; (2) recording responses only from the subgenual organ complex after ablation of the distal tibial chordotonal organ, and (3) the attachment of the leg to the minishaker by plastilin, beeswax-colophony, or freely standing legs. The tibial scolopidial organs give summed responses to vibration stimuli with highest sensitivity between 500 and 1000Hz for all leg pairs. In the different experimental series, we find that (1) thresholds were influenced by stimulation direction with lower thresholds in response to vertical vibrations, (2) ablating the distal tibial chordotonal organ by cutting the distal-most tibia did not change the summed sensory thresholds significantly, and (3) the attachment material between legs and the minishaker (plastilin or beeswax-colophony mixture) did not significant influence the sensory thresholds against free-standing tarsi. The distal tibial chordotonal organ is a connective chordotonal organ attached to a tendon and is likely a proprioceptive organ. These results emphasise that vibrational thresholds are mainly direction-sensitive. Thus, the direction of stimulus delivery during electrophysiological recordings is relevant for comparisons of

  14. Biomedicine's Electronic Publishing Paradigm Shift

    PubMed Central

    Markovitz, Barry P.

    2000-01-01

    Biomedical publishing stands at a crossroads. The traditional print, peer-reviewed, subscription journal has served science well but is now being called into question. Because of spiraling print journal costs and the worldwide acceptance of the Internet as a valid publication medium, there is a compelling opportunity to re-examine our current paradigm and future options. This report illustrates the conflicts and restrictions inherent in the current publishing model and examines how the single act of permitting authors to retain copyright of their scholarly manuscripts may preserve the quality-control function of the current journal system while allowing PubMed Central, the Internet archiving system recently proposed by the director of the National Institutes of Health, to simplify and liberate access to the world's biomedical literature. PMID:10833158

  15. Datacubes as a Service Paradigm

    NASA Astrophysics Data System (ADS)

    Rossi, Angelo Pio; Baumann, Peter

    2016-04-01

    Spatio-temporal data sets often can be represented conveniently through datacubes as a common unifying paradigm. Flexible, scalable services can be offered based on the concept of a datacube query language while hiding the technicalities, thereby allowing user-friendly visual data interaction. One of today's most influential initiatives in Big Geo Data is EarthServer which is paving the way for flexible, scalable datacube services based on innovative NewSQL technology (Fig. 1). Researchers from Europe, the US and recently Australia have teamed up to rigorously materialize the datacube paradigm for Earth Observation, ocean, meteorological, and planetary science. EarthServer has established client and server technology for such spatio-temporal datacubes strictly based on the open datacube standards, OGC WCS and WPCS. The underlying scalable array engine, rasdaman, enables direct interaction, including 3-D visualization, what-if scenarios, common EO data processing, and general analytics on regular and irregular grids. Integration of datacube and metadata retrieval, together with advanced visualization based on NASA WorldWind, are geared towards an effective, user-friendly access and analysis. Conversely, EarthServer is significantly shaping the ISO, OGC, and INSPIRE Big Data standards landscape by being specification editor. Phase 1 of EarthServer has advanced scalable array data¬base technology into 100+ TB services; in phase 2, a federation of Petabyte datacubes is being built in Europe and Australia to perform ad-hoc querying and merging. Phase 1 reviewers have attested rasdaman to "significantly transform the way that scientists in different areas of Earth Science will be able to access and use data in a way that hitherto was not possible". Altogether, these large-scale deployments prove that datacubes are a convenient model for presenting users with a simple, consolidated view on the massive amount of data files gathered - "a cube tells more than a million

  16. Encoding and choice in the task span paradigm.

    PubMed

    Reiman, Kaitlin M; Weaver, Starla M; Arrington, Catherine M

    2015-03-01

    Cognitive control during sequences of planned behaviors requires both plan-level processes such as generating, maintaining, and monitoring the plan, as well as task-level processes such as selecting, establishing and implementing specific task sets. The task span paradigm (Logan in J Exp Psychol Gen 133:218-236, 2004) combines two common cognitive control paradigms, task switching and working memory span, to investigate the integration of plan-level and task-level processes during control of sequential behavior. The current study expands past task span research to include measures of encoding processes and choice behavior with volitional sequence generation, using the standard task span as well as a novel voluntary task span paradigm. In two experiments, we consider how sequence complexity, defined separately for plan-level and task-level complexity, influences sequence encoding (Experiment 1), sequence choice (Experiment 2), sequence memory, and task performance of planned sequences of action. Results indicate that participants were sensitive to sequence complexity, but that different aspects of behavior are most strongly influenced by different types of complexity. Hierarchical complexity at the plan level best predicts voluntary sequence generation and memory; while switch frequency at the task level best predicts encoding of externally defined sequences and task performance. Furthermore, performance RTs were similar for externally and internally defined plans, whereas memory was improved for internally defined sequences. Finally, participants demonstrated a significant sequence choice bias in the voluntary task span. Consistent with past research on choice behavior, volitional selection of plans was markedly influenced by both the ease of memory and performance.

  17. Application of the C(18)-carboxypropylbetaine specimen processing method to recovery of Mycobacterium avium subsp. paratuberculosis from ruminant tissue specimens.

    PubMed

    Thornton, Charles G; MacLellan, Kerry M; Stabel, Judith R; Carothers, Christine; Whitlock, Robert H; Passen, Selvin

    2002-05-01

    The causative agent of Johne's disease is Mycobacterium avium subsp. paratuberculosis. This is a chronic, debilitating gastrointestinal disorder that affects ruminants and is responsible for significant economic loss. The specimen processing method that combines C(18)-carboxypropylbetaine (CB-18) treatment and lytic enzyme decontamination has been shown to improve the diagnosis of mycobacterioses. This processing method was applied to the isolation of M. avium subsp. paratuberculosis from ruminant tissue samples. The BACTEC 12B liquid culture system was used but was supplemented with 1% egg yolk emulsion, 4 microg of mycobactin J, and 0.5% pyruvate (12B/EMP) for use in conjunction with this method. The final concentration of antibiotics used was 10 microg of vancomycin, 30 microg of amphotericin B, and 20 microg of nalidixic acid (VAN) per ml. A 7H10-based solid medium was also used that included mycobactin J, pyruvate, and VAN but excluded the egg yolk emulsion (7H10/MPV). Several M. avium subsp. paratuberculosis isolates were examined during the evaluation of this processing method. It was observed that treatment with lytic enzymes stimulated the growth of M. avium subsp. paratuberculosis; however, the growth of one isolate was markedly inhibited due to the presence of vancomycin. Subsequently, the vancomycin concentration in the VAN formulation was reduced to 2 microg/ml. A blinded panel of 60 previously characterized tissue samples from bovine and bison were then processed and analyzed by smear and culture. Historically, 31 and 37 specimens were classified as positive by histology and culture, respectively. The overall sensitivity and specificity of smear relative to culture following CB-18 processing were 97.6 and 89.5%, respectively. The 12B/EMP/VAN liquid culture system recovered M. avium subsp. paratuberculosis from 39 specimens, whereas 7H10/MPV and Herrold's egg yolk media recovered M. avium subsp. paratuberculosis from 26 and 16 specimens, respectively

  18. Clofazimine Prevents the Regrowth of Mycobacterium abscessus and Mycobacterium avium Type Strains Exposed to Amikacin and Clarithromycin

    PubMed Central

    Ferro, Beatriz E.; Meletiadis, Joseph; Wattenberg, Melanie; de Jong, Arjan; van Soolingen, Dick; Mouton, Johan W.

    2015-01-01

    Multidrug therapy is a standard practice when treating infections by nontuberculous mycobacteria (NTM), but few treatment options exist. We conducted this study to define the drug-drug interaction between clofazimine and both amikacin and clarithromycin and its contribution to NTM treatment. Mycobacterium abscessus and Mycobacterium avium type strains were used. Time-kill assays for clofazimine alone and combined with amikacin or clarithromycin were performed at concentrations of 0.25× to 2× MIC. Pharmacodynamic interactions were assessed by response surface model of Bliss independence (RSBI) and isobolographic analysis of Loewe additivity (ISLA), calculating the percentage of statistically significant Bliss interactions and interaction indices (I), respectively. Monte Carlo simulations with predicted human lung concentrations were used to calculate target attainment rates for combination and monotherapy regimens. Clofazimine alone was bacteriostatic for both NTM. Clofazimine-amikacin was synergistic against M. abscessus (I = 0.41; 95% confidence interval [CI], 0.29 to 0.55) and M. avium (I = 0.027; 95% CI, 0.007 to 0.048). Based on RSBI analysis, synergistic interactions of 28.4 to 29.0% and 23.2 to 56.7% were observed at 1× to 2× MIC and 0.25× to 2× MIC for M. abscessus and M. avium, respectively. Clofazimine-clarithromycin was also synergistic against M. abscessus (I = 0.53; 95% CI, 0.35 to 0.72) and M. avium (I = 0.16; 95% CI, 0.04 to 0.35), RSBI analysis showed 23.5% and 23.3 to 53.3% at 2× MIC and 0.25× to 0.5× MIC for M. abscessus and M. avium, respectively. Clofazimine prevented the regrowth observed with amikacin or clarithromycin alone. Target attainment rates of combination regimens were >60% higher than those of monotherapy regimens for M. abscessus and M. avium. The combination of clofazimine with amikacin or clarithromycin was synergistic in vitro. This suggests a potential role for clofazimine in treatment regimens that warrants further

  19. Is This the Paradigm Shift We Need?

    ERIC Educational Resources Information Center

    Mirvis, Jonathan

    2012-01-01

    Dr. Woocher's essay, states Mirvis, is seminal in the field of Jewish education. It proposes a new paradigm for Jewish education in North America. This proposed paradigm is supported by a comprehensive multi-disciplinary research drawing on literature from education, philosophy, history, sociology, psychology, and economics. The essay reflects a…

  20. Research Paradigms and Meaning Making: A Primer

    ERIC Educational Resources Information Center

    Krauss, Steven Eric

    2005-01-01

    An introduction and explanation of the epistemological differences of quantitative and qualitative research paradigms is first provided, followed by an overview of the realist philosophical paradigm, which attempts to accommodate the two. From this foundational discussion, the paper then introduces the concept of meaning making in research methods…

  1. Paradigm Lost: The Human Chromosome Story.

    ERIC Educational Resources Information Center

    Unger, Lawrence; Blystone, Robert V.

    1996-01-01

    Discusses whether the discovery in 1956 that humans have a chromosome number of 46, as opposed to 47 or 48 as previously thought, fits into a paradigm shift of the Kuhnian type. Concludes that Kuhn probably would not have considered the chromosome number shift to be large enough to be a focus for one of his paradigms. (AIM)

  2. The New Paradigm Dialogs and Qualitative Inquiry

    ERIC Educational Resources Information Center

    Denzin, Norman K.

    2008-01-01

    This paper re-engages the paradigm wars of the 1980s, discussing their relevance in the current historical moment. It extends Egon Guba's call for dialogue across paradigm communities. Ten theses and three agenda items are advanced. (Contains 4 notes.)

  3. The Three Paradigms of Mass Media Research.

    ERIC Educational Resources Information Center

    Potter, W. James; And Others

    A study examined the mass media research literature to determine if there was a dominant paradigm in the field. The mass media research published in eight communication journals from 1965 to 1989 was content analyzed to identify paradigm, orientation (focus and theory), data (type, source, and sample), methodology (type and manipulation), and…

  4. The Due Care Paradigm of School Leadership.

    ERIC Educational Resources Information Center

    Osborne, Bill

    The Due Care paradigm for the successful restructuring of organizations is presented in this paper, with attention to the paradigm's role in creating a fundamental shift from vertical (top/down) decision making to shared governance. The first section explains how due care is linked to three legal terms in tort law--substantive due process, due…

  5. Th Matching Paradigm: An Exact Test Procedure.

    ERIC Educational Resources Information Center

    Gillett, Raphael

    1985-01-01

    Provides a framework based on rook methodology for constructing exact unweighted tests in the matching paradigm. This paradigm tests whether a one-to-one pairing configuration between objects in two arrays contains more pairings of a particular kind than expected under the null hypothesis. The procedure is particularly useful for small samples.…

  6. Mercury biogeochemistry: Paradigm shifts, outstanding issues and research needs

    NASA Astrophysics Data System (ADS)

    Sonke, Jeroen E.; Heimbürger, Lars-Eric; Dommergue, Aurélien

    2013-05-01

    Half a century of mercury research has provided scientists and policy makers with a detailed understanding of mercury toxicology, biogeochemical cycling and past and future impacts on human exposure. The complexity of the global biogeochemical mercury cycle has led to repeated and ongoing paradigm shifts in numerous mercury-related disciplines and outstanding questions remain. In this review, we highlight some of the paradigm shifts and questions on mercury toxicity, the risks and benefits of seafood consumption, the source of mercury in seafood, and the Arctic mercury cycle. We see a continued need for research on mercury toxicology and epidemiology, for marine mercury dynamics and ecology, and for a closer collaboration between observational mercury science and mercury modeling in general. As anthropogenic mercury emissions are closely tied to the energy cycle (in particular coal combustion), mercury exposure to humans and wildlife are likely to persist unless drastic emission reductions are put in place.

  7. Developing sustainable software solutions for bioinformatics by the " Butterfly" paradigm.

    PubMed

    Ahmed, Zeeshan; Zeeshan, Saman; Dandekar, Thomas

    2014-01-01

    Software design and sustainable software engineering are essential for the long-term development of bioinformatics software. Typical challenges in an academic environment are short-term contracts, island solutions, pragmatic approaches and loose documentation. Upcoming new challenges are big data, complex data sets, software compatibility and rapid changes in data representation. Our approach to cope with these challenges consists of iterative intertwined cycles of development (" Butterfly" paradigm) for key steps in scientific software engineering. User feedback is valued as well as software planning in a sustainable and interoperable way. Tool usage should be easy and intuitive. A middleware supports a user-friendly Graphical User Interface (GUI) as well as a database/tool development independently. We validated the approach of our own software development and compared the different design paradigms in various software solutions.

  8. Evidence of disseminated infection by Mycobacterium avium subspecies hominissuis in a pet ferret (Mustela putorius furo).

    PubMed

    Bezos, Javier; Álvarez-Carrión, Beatriz; Rodríguez-Bertos, Antonio; Fernández-Manzano, Álvaro; de Juan, Lucía; Huguet, Cristina; Briones, Víctor; Romero, Beatriz

    2016-12-01

    The infection caused by the zoonotic opportunistic pathogen Mycobacterium avium subsp. hominissuis (Mah) was reported for the first time in a pet ferret. Both owners were HIV-positive. Euthanasia of the pet was recommended due to medical reasons and as a preventive action. Disseminated and open tuberculosis lesions were observed in the gastrointestinal and respiratory systems of the ferret. Ecographic and radiographic surveys showed a severe generalized lymphadenopathy, strong thickening of the gastric wall and peritoneum layer. The histopathological findings revealed a disseminated, granulomatous, chronic inflammation affecting the gastrointestinal tract, lungs, lymphoid tissues (spleen, tonsils and lymph nodes) and liver. Ziehl-Neelsen staining displayed the presence of positive acid-fast bacilli within these granulomas. Bacteriology and sequencing of the isolates yielded Mah sequevar code 3. Ferrets can act as reservoirs of mycobacteria exposing their owners to the infection, which is of major concern in immunodeficient individuals, as those HIV-infected.

  9. Detection of Mycobacterium avium subsp. paratuberculosis by a Direct In Situ PCR Method

    PubMed Central

    Delgado, Fernando; Aguilar, Diana; Garbaccio, Sergio; Francinelli, Gladys; Hernández-Pando, R.; Romano, María Isabel

    2011-01-01

    In situ detection of Mycobacterium avium subsp. paratuberculosis is useful for diagnosis and research of paratuberculosis. The aim of this paper was to detect this agent in formalin-fixed, paraffin-embedded tissue samples by a direct in situ PCR. The technique was performed on ileum or ileocaecal lymph node samples from 8 naturally infected cattle and 1 healthy calf, by using p89 and p92 primers for amplification of IS900 sequence. Moderate positive signal was detected in all positive samples and not in negative control, but tissues resulted were affected in many cases due to the enzymatic treatment and the high temperature exposition. Although the technique was useful for Map detection, the signal was lower than immunohistochemistry probably because of the fixation process. In one case, signal was higher, which might be due to the detection of spheroplasts. Thus, the described method should be recommended when others resulted negative or for spheroplasts detection. PMID:21772965

  10. Seroprevalence of Mycobacterium avium subspecies paratuberculosis in Korean black goats (Capra hircus aegagrus).

    PubMed

    Lee, Kyung Woo; Jung, Byeong Yeal; Moon, Oun Kyoung; Yang, Dong Kun; Lee, Su Hwa; Kim, Ji Yeon; Kweon, Chang Hee

    2006-12-01

    In total, 582 sera from 116 black goat herds were analyzed by a commercially available ELISA kit to monitor the seroprevalence of Mycobacterium avium subspecies paratuberculosis (Mpt) in Korean black goats (Capra hircus aegagrus). The mean number of goats sampled per herd was 5.11, 4.66, and 5.38 for the northern, central, and southern regions of Korea, respectively. The apparent regional prevalence of Mpt was estimated at 18.2-38.2% and 4.6-15.3% for herds and goats, respectively. The Mpt-positive goats were predominantly detected in the south (n=28), compared to either the northern (n=9) or central (n=11) regions (chi=14.459, P<0.05). Our findings indicate that Mpt is prevalent among the goat population, but regional variation exists.

  11. Interferon gamma response to Mycobacterium avium subsp. paratuberculosis specific lipopentapeptide antigen L5P in cattle.

    PubMed

    Holbert, Sébastien; Branger, Maxime; Souriau, Armel; Lamoureux, Bérénice; Ganneau, Christelle; Richard, Gaëlle; Cochard, Thierry; Tholoniat, Christophe; Bay, Sylvie; Winter, Nathalie; Moyen, Jean Louis; Biet, Franck

    2015-10-01

    After Mycobacterium avium subsp. paratuberculosis (Map) infection the cell-mediated immune (CMI) response indicative of early Th1 activation may be detected using interferon-gamma release assay (IGRA). Currently, the purified protein derivatives (PPDs), i.e., the total extract of mycobacteria antigens are used to recall CMI responses against Map. This study aimed to assess the ability of the chemically synthesized Map specific cell wall lipopentapeptide L5P to induce CMI response in cows infected by Map compared to PPD. L5P and PPD elicited an IFN-γ response in 12 and 35 animals from two Map infected herds respectively, but IFN-γ was not detected in the 13 cows recruited from a non-infected herd. Levels of IFN-γ detected were higher with PPD than with L5P. There was no correlation between the IFN-γ response and the humoral response to Map or faecal culture.

  12. Mycobacterium avium subsp. paratuberculosis sheep strains isolated from Cyprus sheep and goats.

    PubMed

    Liapi, M; Botsaris, G; Slana, I; Moravkova, M; Babak, V; Avraam, M; Di Provvido, A; Georgiadou, S; Pavlik, I

    2015-04-01

    Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a chronic incurable infection of intestinal tract of animals. Molecular characterization of Map isolates classifies them into two major groups, 'Cattle' or Type II and 'Sheep' or Type I/III with a different phenotype, epidemiology, virulence and pathogenesis. The aim of this study was to examine 192 Map ELISA-positive sheep and goats from Cyprus using faecal culture and genotype Map isolates using IS1311 PCR and restriction endonuclease analysis (IS1311 PCR-REA) with HinfI restriction enzyme. Map was isolated from only four (4.6%) faecal samples out of 88 sheep and 15 (14.4%) faecal samples out of 104 goats. Genotyping of the isolates using IS1311 PCR-REA revealed that sheep and goat populations on the island are infected primarily by 'Sheep' strains. Only three Map isolates from goats originated from one farm were characterized as 'Cattle' strains.

  13. Spread of Mycobacterium avium subsp. paratuberculosis through soil and grass on a mouflon (Ovis aries) pasture.

    PubMed

    Kaevska, Marija; Lvoncik, S; Lamka, J; Pavlik, I; Slana, I

    2014-10-01

    The aims of this study were to describe spatial contamination of the environment on a mouflon pasture, as well as to assess the contamination of grass and roots after surface contamination and in depth contamination with feces and buried tissues from animals infected with Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis). Samples of soil, roots, and aerial parts of plants were collected from different locations inside the mouflon pasture, and one control sample site was chosen outside the area where the animals are living. M. a. paratuberculosis DNA was present in all the examined sites and was more often detected in roots than in soil. DNA was detected at up to 80 cm of depth and was spatially more widespread than the initial hypothesis of M. a. paratuberculosis leaching vertically into deeper layers of soil. This study broadens our knowledge of the spread and persistence of M. a. paratuberculosis in an environment with highly infected animals.

  14. Mycobacterium avium-related epizootic in free-ranging lesser flamingos in Kenya.

    PubMed

    Kock, N D; Kock, R A; Wambua, J; Kamau, G J; Mohan, K

    1999-04-01

    An epizootic in free-ranging lesser flamingos (Phoeniconaias minor) in Kenya resulted in more than 18,500 deaths from August through mid-November 1993. Disease was concentrated along the shores of Rift Valley Lakes Bogoria and Nakuru (Kenya) and did not involve any of the other avian or mammalian species frequenting the lakes. Coincidental to the outbreak was a bloom of algae on Lake Bogoria, toxins from which were first suspected to be causative. Discrete necrotic and granulomatous lesions were often noted in spleen and liver, and Mycobacterium avium serovar I was isolated from both organs. Escherichia coli and Pseudomonas aeruginosa also were often recovered in pure culture from liver. Gross and histopathological evaluation of the cases disclosed signs of acute sepsis and also chronic, potentially life-threatening lesions of mycobacteriosis, primarily involving the spleen and liver. Lesions typical for algae toxicosis were not seen in any birds. Deaths were attributed to septicemia complicated in those affected, by mycobacteriosis.

  15. Genetic diversity in wild sweet cherries (Prunus avium) in Turkey revealed by SSR markers.

    PubMed

    Ercisli, S; Agar, G; Yildirim, N; Duralija, B; Vokurka, A; Karlidag, H

    2011-06-21

    Wild sweet cherry (Prunus avium) trees are abundant in the northern part of Turkey, including the Coruh Valley. We analyzed 18 wild sweet cherry genotypes collected from diverse environments in the upper Coruh Valley in Turkey to determine genetic variation, using 10 SSR primers. These SSR primers generated 46 alleles; the number of alleles per primer ranged from 3 to 7, with a mean of 4.6. The primer PS12A02 gave the highest number of polymorphic bands (N = 7), while CPSCT010, UDAp-401 and UDAp-404 gave the lowest number (N = 3). Seven groups were separated in the dendrogram, although most of the genotypes did not cluster according to phenological and morphological traits. This level of genetic diversity in these wild sweet cherry genotypes is very high and therefore these trees would be useful as breeders for crosses between cultivated sweet cherry and wild genotypes.

  16. Association between cattle herd Mycobacterium avium subsp. paratuberculosis (MAP) infection and infection of a hare population.

    PubMed

    Salgado, Miguel; Monti, Gustavo; Sevilla, Iker; Manning, Elizabeth

    2014-10-01

    Paratuberculosis has long been considered a disease of domestic and wild ruminants only. The known host range of Mycobacterium avium subsp. paratuberculosis (MAP) was recently extended to include non-ruminant wildlife species believed to be exposed to spillover of MAP from infected domestic cattle herds. The aim of the present study was to assess the association between cattle herd MAP infection pressure level and the infection level of a hare population in two dairy farms of southern Chile. Fifty hares from a herd A and 42 hares from herd B were captured and sampled for MAP culture. The results showed a statistically significant association between the cattle herds' infection prevalence and the hare infection prevalence.

  17. Paradigm shift in lead design.

    PubMed

    Irnich, W

    1999-09-01

    During the past 30 years there has been a tremendous development in electrode technology from bulky (90 mm2) to pin-sized (1.0 mm2) electrodes. Simultaneously, impedance has increased from 110 Ohms to >1 kOhms, which has been termed a "paradigm shift" in lead design. If current is responsible for stimulation, why is its impedance a key factor in saving energy? Further, what mechanism is behind this development based on experimental findings and what conclusion can be drawn from it to optimize electrode size? If it is assumed that there is always a layer of nonexcitable tissue between the electrode surface and excitable myocardium and that the electric field (potential gradient) produced by the electrode at this boundary is reaching threshold level, then a formula can be derived for the voltage threshold that completely describes the electrophysiology and electrophysics of a hemispherical electrode. Assuming that the mean chronic threshold for porous steroid-eluting electrodes is 0.6 V with 0.5-ms pulse duration, thickness of nonexcitable tissue can be estimated to be 1.5 mm. Taking into account this measure and the relationship between chronaxie and electrode area, voltage threshold, impedance, and energy as a function of surface area can be calculated. The lowest voltage for 0.5-ms pulse duration is reached with r(o) = 0.5 d, yielding a surface area of 4 mm2 and a voltage threshold of 0.62 V, an impedance of 1 kOhms, and an energy level of 197 nJ. It can be deduced from our findings that a further reduction of surface areas below 1.6 mm2 will not diminish energy threshold substantially, if pulse duration remains at 0.5 ms. Lowest energy is reached with t = chronaxie, yielding an energy level <100 nJ with surface areas < or =1.5 mm2. It is striking to see how well the theoretically derived results correspond to the experimental findings. It is also surprising that the hemispheric model so accurately approximates experimental results with differently shaped

  18. Induction of murine macrophage TNF-alpha synthesis by Mycobacterium avium is modulated through complement-dependent interaction via complement receptors 3 and 4 in relation to M. avium glycopeptidolipid.

    PubMed

    Irani, Vida R; Maslow, Joel N

    2005-05-15

    We studied whether complement receptor (CR) mediated Mycobacterium avium interaction modulated macrophage TNF-alpha expression. Compared to control conditions, infections performed with C3-depletion yielded significantly higher TNF-alpha levels. Blockage of the CR4 iC3b site yielded increases in TNF-alpha for all morphotypic variants of a virulent serovar-8 strain (smooth transparent (SmT), smooth opaque (SmO), serovar-specific glycopeptidolipid (ssGPL) deficient knockout mutant) whereas CR3 blockage increased TNF-alpha only for SmT and ssGPL-deficient strains. Thus, complement-mediated binding of M. avium to CR3 and CR4 was shown to modulate TNF-alpha expression. The differential activation of morphotypic and isogenic variants of a single strain provides an excellent model system to delineate signaling pathways.

  19. Comparison of the conventional culture, the manual fluorescent MGIT system and the automated fluorescent MGIT 960 culture system for the detection of Mycobacterium avium ssp. avium in tissues of naturally infected hens.

    PubMed

    Shitaye, E J; Beran, V; Svobodová, J; Morávková, M; Babák, V; Pavlík, I

    2009-01-01

    Different methods for the detection of Mycobacterium avium ssp. avium (MAA) in naturally infected hens were compared. They included the conventional culture method (solid Herrold's and Stonebrink media and liquid Sula medium) and newly developed liquid culture systems, the manual mycobacteria growth indicator tube (M-MGIT) and the fully automated BACTEC MGIT 960 system (A-MGIT). 152 tissues originating from 15 naturally infected hens have been processed. The overall detection rates (percentage of positive cultures from the number of positive cultures determined by all the methods together) were 60, 70 and 76 % for the conventional media, M-MGIT and A-MGIT systems, respectively, the mean time of mycobacteria detection being 32.6, 17.6 and 14.6 d, respectively. The lowest contamination rate (2.0 %) was found in A-MGIT compared with M-MGIT (4.6 %) and conventional media (10.4 %).

  20. Superoxide dismutase activity of Mycobacterium avium, M. intracellulare, and M. scrofulaceum.

    PubMed Central

    Mayer, B K; Falkinham, J O

    1986-01-01

    Superoxide dismutase (EC 1.15.1.1) (SOD) activity has been detected in crude cell extracts of representative strains of the Mycobacterium avium, M. intracellulare, and M. scrofulaceum (MAIS) group. Polyacrylamide gel electrophoresis demonstrated a single SOD activity band for each of the MAIS strains, though there were differences in mobility. All M. avium and M. intracellulare and two of five M. scrofulaceum strains demonstrated a single activity band of identical mobility (Rf = 0.83), while the SOD activity band for the three remaining M. scrofulaceum strains migrated farther (Rf = 0.85). The differences in mobility correlated with differences in sensitivity to NaN3 and H2O2. The SOD activities of the majority of the MAIS strains which displayed the slower-migrating activity band were inhibited 22 to 81% after 15 min of exposure to 5 mM H2O2, suggesting that both iron and manganese may be present in a single enzyme. The SOD activities of the three M. scrofulaceum strains which had the faster-migrating activity band were inhibited 100% after only 5 min of exposure to 5 mM H2O2 and exhibited greater sensitivity to 5 and 10 mM NaN3, characteristics of an iron-containing SOD. A concentration of 1 mM KCN did not cause inhibition of enzyme activity in any of the MAIS strains tested. Extracellular SOD activity was detected in four of six MAIS strains and was shown to be identical in mobility to the SOD activity of the crude extracts. Images PMID:3744555

  1. Mycobacterium avium Possesses Extracellular DNA that Contributes to Biofilm Formation, Structural Integrity, and Tolerance to Antibiotics

    PubMed Central

    Rose, Sasha J.; Babrak, Lmar M.; Bermudez, Luiz E.

    2015-01-01

    Mycobacterium avium subsp. hominissuis is an opportunistic pathogen that is associated with biofilm-related infections of the respiratory tract and is difficult to treat. In recent years, extracellular DNA (eDNA) has been found to be a major component of bacterial biofilms, including many pathogens involved in biofilm-associated infections. To date, eDNA has not been described as a component of mycobacterial biofilms. In this study, we identified and characterized eDNA in a high biofilm-producing strain of Mycobacterium avium subsp. hominissuis (MAH). In addition, we surveyed for presence of eDNA in various MAH strains and other nontuberculous mycobacteria. Biofilms of MAH A5 (high biofilm-producing strain) and MAH 104 (reference strain) were established at 22°C and 37°C on abiotic surfaces. Acellular biofilm matrix and supernatant from MAH A5 7 day-old biofilms both possess abundant eDNA, however very little eDNA was found in MAH 104 biofilms. A survey of MAH clinical isolates and other clinically relevant nontuberculous mycobacterial species revealed many species and strains that also produce eDNA. RAPD analysis demonstrated that eDNA resembles genomic DNA. Treatment with DNase I reduced the biomass of MAH A5 biofilms when added upon biofilm formation or to an already established biofilm both on abiotic surfaces and on top of human pharyngeal epithelial cells. Furthermore, co-treatment of an established biofilm with DNase 1 and either moxifloxacin or clarithromycin significantly increased the susceptibility of the bacteria within the biofilm to these clinically used antimicrobials. Collectively, our results describe an additional matrix component of mycobacterial biofilms and a potential new target to help treat biofilm-associated nontuberculous mycobacterial infections. PMID:26010725

  2. Mycobacterium avium Subspecies paratuberculosis Recombinant Proteins Modulate Antimycobacterial Functions of Bovine Macrophages

    PubMed Central

    Bannantine, John P.; Stabel, Judith R.; Laws, Elizabeth; D. Cardieri, Maria Clara; Souza, Cleverson D.

    2015-01-01

    It has been shown that Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) activates the Mitogen Activated Protein Kinase (MAPK) p38 pathway, yet it is unclear which components of M. paratuberculosis are involved in the process. Therefore, a set of 42 M. paratuberculosis recombinant proteins expressed from coding sequences annotated as lipoproteins were screened for their ability to induce IL-10 expression, an indicator of MAPKp38 activation, in bovine monocyte-derived macrophages. A recombinant lipoprotein, designated as MAP3837c, was among a group of 6 proteins that strongly induced IL-10 gene transcription in bovine macrophages, averaging a 3.1-fold increase compared to non-stimulated macrophages. However, a parallel increase in expression of IL-12 and TNF-α was only observed in macrophages exposed to a subset of these 6 proteins. Selected recombinant proteins were further analyzed for their ability to enhance survival of M. avium within bovine macrophages as measured by recovered viable bacteria and nitrite production. All 6 IL-10 inducing MAP recombinant proteins along with M. paratuberculosis cells significantly enhanced phosphorylation of MAPK-p38 in bovine macrophages. Although these proteins are likely not post translationally lipidated in E. coli and thus is a limitation in this study, these results form the foundation of how the protein component of the lipoprotein interacts with the immune system. Collectively, these data reveal M. paratuberculosis proteins that might play a role in MAPK-p38 pathway activation and hence in survival of this organism within bovine macrophages. PMID:26076028

  3. GENETIC DIVERSITY OF SOME IRANIAN SWEET CHERRY (PRUNUS AVIUM) CULTIVARS USING MICROSATELLITE MARKERS AND MORPHOLOGICAL TRAITS.

    PubMed

    Farsad, A; Esna-Ashari, M

    2016-01-01

    The aim of this study was to characterize 23 important Iranian sweet cherry (Prunus avium) cultivars collected from different provinces of Iran and 1 foreign cultivar, which was used as control, considered for breeding programs by using 21 microsatellite markers and 27 morphological traits. In sweet cherry (Prunus avium) accessions, leaf, fruit, and stone morphological characters were evaluated during two consecutive years. The study revealed a high variability in the set of evaluated sweet cherry accessions. The majority of important correlations were determined among variables representing fruit and leaf size and variables related to color. Cluster analysis distinguished sweet cherry accessions into two distinct groups. Principal component analysis (PCA) of qualitative and quantitative morphological parameters explained over 86.59% of total variability in the first seven axes. In PCA, leaf traits such as leaf length and width, and fruit traits such as length, width, and weight, and fruit flesh and juice color were predominant in the first two components, indicating that they were useful for the assessment of sweet cherry germplasm characterization. Out of 21 SSR markers, 16 were polymorphic, producing 177 alleles that varied from 4 to 16 alleles (9.35 on average) with a mean heterozygosity value of 0.82 that produced successful amplifications and revealed DNA polymorphisms. Allele size varied from 95 to 290 bp. Cluster analyses showed that the studied sweet cherry genotypes were classified intofive main groups based mainly on their species characteristics and SSR data. In general, our results did not show a clear structuring of genetic variability within the Iranian diffusion area of sweet cherry, so it was not possible to draw any indications on regions of provenance delimitation. The results of this study contribute to a better understanding of sweet cherry genetic variations in Iran, thus making for more efficient programs aimed at preserving biodiversity and

  4. Mycobacterium avium Possesses Extracellular DNA that Contributes to Biofilm Formation, Structural Integrity, and Tolerance to Antibiotics.

    PubMed

    Rose, Sasha J; Babrak, Lmar M; Bermudez, Luiz E

    2015-01-01

    Mycobacterium avium subsp. hominissuis is an opportunistic pathogen that is associated with biofilm-related infections of the respiratory tract and is difficult to treat. In recent years, extracellular DNA (eDNA) has been found to be a major component of bacterial biofilms, including many pathogens involved in biofilm-associated infections. To date, eDNA has not been described as a component of mycobacterial biofilms. In this study, we identified and characterized eDNA in a high biofilm-producing strain of Mycobacterium avium subsp. hominissuis (MAH). In addition, we surveyed for presence of eDNA in various MAH strains and other nontuberculous mycobacteria. Biofilms of MAH A5 (high biofilm-producing strain) and MAH 104 (reference strain) were established at 22°C and 37°C on abiotic surfaces. Acellular biofilm matrix and supernatant from MAH A5 7 day-old biofilms both possess abundant eDNA, however very little eDNA was found in MAH 104 biofilms. A survey of MAH clinical isolates and other clinically relevant nontuberculous mycobacterial species revealed many species and strains that also produce eDNA. RAPD analysis demonstrated that eDNA resembles genomic DNA. Treatment with DNase I reduced the biomass of MAH A5 biofilms when added upon biofilm formation or to an already established biofilm both on abiotic surfaces and on top of human pharyngeal epithelial cells. Furthermore, co-treatment of an established biofilm with DNase 1 and either moxifloxacin or clarithromycin significantly increased the susceptibility of the bacteria within the biofilm to these clinically used antimicrobials. Collectively, our results describe an additional matrix component of mycobacterial biofilms and a potential new target to help treat biofilm-associated nontuberculous mycobacterial infections.

  5. Dealing with a Paradigm Shift

    PubMed Central

    Pack, Allan I.

    2015-01-01

    Recent changes in policies by insurance companies with respect to mandating home sleep apnea testing rather than in-laboratory studies have a large impact on the financial viability of clinical sleep centers. Coping with this disruptive change requires forward planning. First, it is important to be well positioned with respect to facilities so that these can be quickly downsized to control costs. There is also a need to develop, in advance, an accredited home sleep study program so that centers can respond to the rapidly changing environment. Following the change there is a need to control costs by rapidly downsizing the technology workforce. Technologists can be retrained for other essential roles. Centralizing the precertification process with knowledgeable, well-trained staff and a robust auditing process is an essential component. The approach taken at the University of Pennsylvania to this change is described as is how one can ensure continued financial viability of a comprehensive sleep center program in a major academic medical center. Citation: Pack AI. Dealing with a paradigm shift. J Clin Sleep Med 2015;11(8):925–929. PMID:26094918

  6. Antiphospholipid antibodies: Paradigm in transition

    PubMed Central

    Horstman, Lawrence L; Jy, Wenche; Bidot, Carlos J; Ahn, Yeon S; Kelley, Roger E; Zivadinov, Robert; Maghzi, Amir H; Etemadifar, Masoud; Mousavi, Seyed Ali; Minagar, Alireza

    2009-01-01

    Objectives This is a critical review of anti-phospholipid antibodies (aPL). Most prior reviews focus on the aPL syndrome (APS), a thrombotic condition often marked by neurological disturbance. We bring to attention recent evidence that aPL may be equally relevant to non-thrombotic autoimmune conditions, notably, multiple sclerosis and ITP. Organization After a brief history, the recent proliferation of aPL target antigens is reviewed. The implication is that many more exist. Theories of aPL in thrombosis are then reviewed, concluding that all have merit but that aPL may have more diverse pathological consequences than now recognized. Next, conflicting results are explained by methodological differences. The lupus anticoagulant (LA) is then discussed. LA is the best predictor of thrombosis, but why this is true is not settled. Finally, aPL in non-thrombotic disorders is reviewed. Conclusion The current paradigm of aPL holds that they are important in thrombosis, but they may have much wider clinical significance, possibly of special interest in neurology. PMID:19154576

  7. Monsoon-Enso Relationships: A New Paradigm

    NASA Technical Reports Server (NTRS)

    Lau, K. M.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    This article is partly a review and partly a new research paper on monsoon-ENSO relationship. The paper begins with a discussion of the basic relationship between the Indian monsoon and ENSO dating back to the work of Sir Gilbert Walker up to research results in more recent years. Various factors that may affect the monsoon-ENSO, relationship, including regional coupled ocean-atmosphere processes, Eurasian snow cover, land-atmosphere hydrologic feedback, intraseasonal oscillation, biennial variability and inter-decadal variations, are discussed. The extreme complex and highly nonlinear nature of the monsoon-ENSO relationship is stressed. We find that for regional impacts on the monsoon, El Nino and La Nina are far from simply mirror images of each other. These two polarities of ENSO can have strong or no impacts on monsoon anomalies depending on the strength of the intraseasonal oscillations and the phases of the inter-decadal variations. For the Asian-Australian monsoon (AAM) as a whole, the ENSO impact is effected through a east-west shift in the Walker Circulation. For rainfall anomalies over specific monsoon areas, regional processes play important roles in addition to the shift in the Walker Circulation. One of the key regional processes identified for the boreal summer monsoon is the anomalous West Pacific Anticyclone (WPA). This regional feature has similar signatures in interannual and intraseasonal time scales and appears to determine whether the monsoon-ENSO relationship is strong or weak in a given year. Another important regional feature includes a rainfall and SST dipole across the Indian Ocean, which may have strong impact on the austral summer monsoon. Results are shown indicating that monsoon surface wind forcings may induce a strong biennial signal in ENSO and that strong monsoon-ENSO coupling may translate into pronounced biennial variability in ENSO. Finally, a new paradigm is proposed for the study of monsoon variability. This paradigm provides

  8. Cloning and sequencing of a gene encoding a 21-kilodalton outer membrane protein from Bordetella avium and expression of the gene in Salmonella typhimurium.

    PubMed Central

    Gentry-Weeks, C R; Hultsch, A L; Kelly, S M; Keith, J M; Curtiss, R

    1992-01-01

    Three gene libraries of Bordetella avium 197 DNA were prepared in Escherichia coli LE392 by using the cosmid vectors pCP13 and pYA2329, a derivative of pCP13 specifying spectinomycin resistance. The cosmid libraries were screened with convalescent-phase anti-B. avium turkey sera and polyclonal rabbit antisera against B. avium 197 outer membrane proteins. One E. coli recombinant clone produced a 56-kDa protein which reacted with convalescent-phase serum from a turkey infected with B. avium 197. In addition, five E. coli recombinant clones were identified which produced B. avium outer membrane proteins with molecular masses of 21, 38, 40, 43, and 48 kDa. At least one of these E. coli clones, which encoded the 21-kDa protein, reacted with both convalescent-phase turkey sera and antibody against B. avium 197 outer membrane proteins. The gene for the 21-kDa outer membrane protein was localized by Tn5seq1 mutagenesis, and the nucleotide sequence was determined by dideoxy sequencing. DNA sequence analysis of the 21-kDa protein revealed an open reading frame of 582 bases that resulted in a predicted protein of 194 amino acids. Comparison of the predicted amino acid sequence of the gene encoding the 21-kDa outer membrane protein with protein sequences in the National Biomedical Research Foundation protein sequence data base indicated significant homology to the OmpA proteins of Shigella dysenteriae, Enterobacter aerogenes, E. coli, and Salmonella typhimurium and to Neisseria gonorrhoeae outer membrane protein III, Haemophilus influenzae protein P6, and Pseudomonas aeruginosa porin protein F. The gene (ompA) encoding the B. avium 21-kDa protein hybridized with 4.1-kb DNA fragments from EcoRI-digested, chromosomal DNA of Bordetella pertussis and Bordetella bronchiseptica and with 6.0- and 3.2-kb DNA fragments from EcoRI-digested, chromosomal DNA of B. avium and B. avium-like DNA, respectively. A 6.75-kb DNA fragment encoding the B. avium 21-kDa protein was subcloned into the

  9. Bacteriostatic and bactericidal activities of benzoxazinorifamycin KRM-1648 against Mycobacterium tuberculosis and Mycobacterium avium in human macrophages.

    PubMed Central

    Mor, N; Simon, B; Heifets, L

    1996-01-01

    Inhibitory and bactericidal activities of KRM-1648 were determined against Mycobacterium tuberculosis and M. avium residing in human monocyte-derived macrophages and extracellular M. tuberculosis and M. avium. MICs and MBCs of KRM-1648 against intracellular and extracellular bacteria were substantially lower than those of rifampin. The MICs and MBCs of either drug against the intracellular bacteria were only twofold lower than or equal to the values found for extracellular bacteria. The prolonged effect of KRM-1648 found in this study is probably associated with high ratios of intracellular accumulation, which were 50- to 100-fold higher than that found for rifampin. Further studies on intracellular distribution of KRM-1648 and on the sites of actual interaction between the drug and bacteria residing in macrophages are necessary, as well as evaluation of combined effects of KRM-1648 with other drugs in long-term macrophage culture experiments. PMID:8726023

  10. Effects of interleukin-12 in the long-term protection conferred by a Mycobacterium avium subunit vaccine.

    PubMed

    Silva, R A; Pais, T F; Appelberg, R

    2000-12-01

    The effects of the addition of recombinant interleukin (IL)-12 to a mycobacterial subunit vaccine were analyzed in terms of the longevity of the protective immunity generated. BALB/c mice were immunized with culture filtrate proteins from Mycobacterium avium with dimethyl-dioctadecilammonium bromide (DDA) as an adjuvant. This subunit vaccine induced protection against a challenge by M. avium which lasted for at least 6 months while waning with time until 1 year postvaccination. Whereas the addition of IL-12 enhanced the initial protective efficacy of this subunit vaccine during the first 6 months, it accelerated the loss of protective efficacy observed at 1 year postvaccination. These data confirm the adjuvant properties of IL-12 in vaccines against mycobacteria and raise the possibility of late counter-protective untoward effects.

  11. Short communication: Heritability estimates for susceptibility to Mycobacterium avium subspecies paratuberculosis infection defined by ELISA and fecal culture test results in Jersey cattle.

    PubMed

    Zare, Y; Shook, G E; Collins, M T; Kirkpatrick, B W

    2014-07-01

    Paratuberculosis (Johne's disease), an enteric disorder in ruminants caused by Mycobacterium avium ssp. paratuberculosis, causes economic losses in excess of $200 million annually to the US dairy industry. Costly diagnostic testing, cumbersome control programs, incurability, and ineffective vaccination all make M. avium ssp. paratuberculosis susceptibility a good candidate for genetic studies and genetic selection a potentially useful adjunct to management-based control programs. No report has been published for heritability of susceptibility to M. avium ssp. paratuberculosis infection in Jersey cattle. The objective of this study was to estimate variance components and heritability for susceptibility to M. avium ssp. paratuberculosis infection in US Jersey cattle. Data consisted of complete serum ELISA and partial fecal culture results on a total of 2,861 Jersey cows from 23 commercial herds throughout the United States after editing. Four M. avium ssp. paratuberculosis susceptibility phenotypes were defined using (1) ELISA sample-to-positive ratios as a continuous trait, (2) ELISA results as a binary trait (positive=1, negative=0), (3) ELISA results as an ordered categorical trait, and (4) a combined test in which ELISA and fecal culture results were both taken into account in a binary analysis. Three statistical models, including linear, binary threshold, and ordered threshold sire models, were used to analyze the data. All analyses were executed using the restricted maximum likelihood method in ASReml 3 software. The heritability estimates were low to moderate and ranged from 0.08 (±0.03) to 0.27 (±0.11) based on different trait definitions. The nonzero heritability indicates that susceptibility to M. avium ssp. paratuberculosis infection in Jersey cattle is influenced by genetic factors. Therefore, selection of the least susceptible animals could decrease genetic predisposition to M. avium ssp. paratuberculosis infection in Jersey populations in future

  12. Military Intelligence Fusion for Complex Operations: A New Paradigm

    DTIC Science & Technology

    2012-01-01

    analytic lexi- con, at least for COIN analysis.55 Instead of dividing analysis between “meat eaters” and “leaf eaters,” all analysts would be omnivores ... Omnivorous analysts would not only consume information from a holistic perspective, but they would also describe the environment holisti- 54 Here, it is...broadly to full-spectrum operations. 56 I draw this language (meat eater, leaf eater, and omnivore ) from Regional Command West Stability Operations

  13. Navigating complex decision spaces: Problems and paradigms in sequential choice

    PubMed Central

    Walsh, Matthew M.; Anderson, John R.

    2015-01-01

    To behave adaptively, we must learn from the consequences of our actions. Doing so is difficult when the consequences of an action follow a delay. This introduces the problem of temporal credit assignment. When feedback follows a sequence of decisions, how should the individual assign credit to the intermediate actions that comprise the sequence? Research in reinforcement learning provides two general solutions to this problem: model-free reinforcement learning and model-based reinforcement learning. In this review, we examine connections between stimulus-response and cognitive learning theories, habitual and goal-directed control, and model-free and model-based reinforcement learning. We then consider a range of problems related to temporal credit assignment. These include second-order conditioning and secondary reinforcers, latent learning and detour behavior, partially observable Markov decision processes, actions with distributed outcomes, and hierarchical learning. We ask whether humans and animals, when faced with these problems, behave in a manner consistent with reinforcement learning techniques. Throughout, we seek to identify neural substrates of model-free and model-based reinforcement learning. The former class of techniques is understood in terms of the neurotransmitter dopamine and its effects in the basal ganglia. The latter is understood in terms of a distributed network of regions including the prefrontal cortex, medial temporal lobes cerebellum, and basal ganglia. Not only do reinforcement learning techniques have a natural interpretation in terms of human and animal behavior, but they also provide a useful framework for understanding neural reward valuation and action selection. PMID:23834192

  14. Paradigm Change: Targeting Enemy Leadership in a Complex Environment

    DTIC Science & Technology

    2011-06-10

    explosives expert of Black September); Mahmoud Hamshari (an intellectual, diplomat, and spokesman for the Palestinian cause); Wael Zwaiter (a key...team hit its first target. The first target was Aedel Wael Zwaiter. Prior to arriving in Rome, the operational team was provided a targeting package

  15. Leprosy: too complex a disease for a simple elimination paradigm.

    PubMed Central

    Lockwood, Diana N. J.; Suneetha, Sujai

    2005-01-01

    Can leprosy be eliminated? This paper considers the question against the background of the WHO programme to eliminate leprosy. In 1991 the World Health Assembly set a target of eliminating leprosy as a public health problem by 2000. Elimination was defined as reaching a prevalence of < 1 case per 10 000 people. The elimination programme has been successful in delivering highly effective antibiotic therapy worldwide. However, despite this advance, new-case detection rates remain stable in countries with the highest rates of endemic leprosy, such as Brazil and India. This suggests that infection has not been adequately controlled by antibiotics alone. Leprosy is perhaps more appropriately classed as a chronic stable disease than as an acute infectious disease responsive to elimination strategies. In many countries activities to control and treat leprosy are being integrated into the general health-care system. This reduces the stigma associated with leprosy. However, leprosy causes long-term immunological complications, disability and deformity. The health-care activities of treating and preventing disabilities need to be provided in an integrated setting. Detecting new cases and monitoring disability caused by leprosy will be a challenge. One solution is to implement long-term surveillance in selected countries with the highest rates of endemic disease so that an accurate estimate of the burden of leprosy can be determined. It is also critical that broad-based research into this challenging disease continues until the problems are truly solved. PMID:15798849

  16. Ostracism Online: A social media ostracism paradigm.

    PubMed

    Wolf, Wouter; Levordashka, Ana; Ruff, Johanna R; Kraaijeveld, Steven; Lueckmann, Jan-Matthis; Williams, Kipling D

    2015-06-01

    We describe Ostracism Online, a novel, social media-based ostracism paradigm designed to (1) keep social interaction experimentally controlled, (2) provide researchers with the flexibility to manipulate the properties of the social situation to fit their research purposes, (3) be suitable for online data collection, (4) be convenient for studying subsequent within-group behavior, and (5) be ecologically valid. After collecting data online, we compared the Ostracism Online paradigm with the Cyberball paradigm (Williams & Jarvis Behavior Research Methods, 38, 174-180, 2006) on need-threat and mood questionnaire scores (van Beest & Williams Journal of Personality and Social Psychology 91, 918-928, 2006). We also examined whether ostracized targets of either paradigm would be more likely to conform to their group members than if they had been included. Using a Bayesian analysis of variance to examine the individual effects of the different paradigms and to compare these effects across paradigms, we found analogous effects on need-threat and mood. Perhaps because we examined conformity to the ostracizers (rather than neutral sources), neither paradigm showed effects of ostracism on conformity. We conclude that Ostracism Online is a cost-effective, easy to use, and ecologically valid research tool for studying the psychological and behavioral effects of ostracism.

  17. Two complementary paradigms for analysing population dynamics.

    PubMed Central

    Krebs, Charles J

    2002-01-01

    To understand why population growth rate is sometimes positive and sometimes negative, ecologists have adopted two main approaches. The most common approach is through the density paradigm by plotting population growth rate against population density. The second approach is through the mechanistic paradigm by plotting population growth rate against the relevant ecological processes affecting the population. The density paradigm is applied a posteriori, works sometimes but not always and is remarkably useless in solving management problems or in providing an understanding of why populations change in size. The mechanistic paradigm investigates the factors that supposedly drive density changes and is identical to Caughley's declining population paradigm of conservation biology. The assumption that we can uncover invariant relationships between population growth rate and some other variables is an article of faith. Numerous commercial fishery applications have failed to find the invariant relationships between stock and recruitment that are predicted by the density paradigm. Environmental variation is the rule, and non-equilibrial dynamics should force us to look for the mechanisms of population change. If multiple factors determine changes in population density, there can be no predictability in either of these paradigms and we will become environmental historians rather than scientists with useful generalizations for the population problems of this century. Defining our questions clearly and adopting an experimental approach with crisp alternative hypotheses and adequate controls will be essential to building useful generalizations for solving the practical problems of population management in fisheries, wildlife and conservation. PMID:12396513

  18. Identification of (+)-erythro-mefloquine as an active enantiomer with greater efficacy than mefloquine against Mycobacterium avium infection in mice.

    PubMed

    Bermudez, Luiz E; Inderlied, Clark B; Kolonoski, Peter; Chee, Christopher B; Aralar, Priscilla; Petrofsky, Mary; Parman, Toufan; Green, Carol E; Lewin, Anita H; Ellis, William Y; Young, Lowell S

    2012-08-01

    Infection caused by Mycobacterium avium is common in AIDS patients who do not receive treatment with highly active antiretroviral therapy (HAART) or who develop resistance to anti-HIV therapy. Mefloquine, a racemic mixture used for malaria prophylaxis and treatment, is bactericidal against M. avium in mice. MICs of (+)-erythro-, (-)-erythro-, (+)-threo-, and (-)-threo-mefloquine were 32 μg/ml, 32 μg/ml, 64 μg/ml, and 64 μg/ml, respectively. The postantibiotic effect for (+)-erythro-mefloquine was 36 h (MIC) and 41 h for a concentration of 4× MIC. The mefloquine postantibiotic effect was 25 h (MIC and 4× MIC). After baseline infection was established (7 days), the (+)- and (-)-isomers of the diastereomeric threo- and erythro-α-(2-piperidyl)-2,8-bis(trifluoromethyl)-4-quinolinemethanol were individually used to orally treat C57BL/6 bg(+)/bg(+) beige mice that were infected intravenously with M. avium. Mice were also treated with commercial mefloquine and diluent as controls. After 4 weeks of treatment, the mice were harvested, and the number of bacteria in spleen and liver was determined. Mice receiving (+)- or (-)-threo-mefloquine or (-)-erythro-mefloquine had numbers of bacterial load in tissues similar to those of untreated control mice at 4 weeks. Commercial mefloquine had a bactericidal effect. However, mice given the (+)-erythro-enantiomer for 4 weeks had a significantly greater reduction of bacterial load than those given mefloquine. Thus, (+)-erythro-mefloquine is the active enantiomer of mefloquine against M. avium and perhaps other mycobacteria.

  19. Two Paradigms of Professional Development in Environmental Education.

    ERIC Educational Resources Information Center

    Robottom, Ian M.

    1987-01-01

    Argues that environmental education in this information age requires a shift from a paradigm of "information technology" to a paradigm of "information critique." Provides a perspective on the form of this paradigm shift in the area of professional development. (TW)

  20. Killing of Mycobacterium avium by Lactoferricin Peptides: Improved Activity of Arginine- and d-Amino-Acid-Containing Molecules

    PubMed Central

    Silva, Tânia; Magalhães, Bárbara; Maia, Sílvia; Gomes, Paula; Nazmi, Kamran; Bolscher, Jan G. M.; Rodrigues, Pedro N.; Bastos, Margarida

    2014-01-01

    Mycobacterium avium causes respiratory disease in susceptible individuals, as well as disseminated infections in immunocompromised hosts, being an important cause of morbidity and mortality among these populations. Current therapies consist of a combination of antibiotics taken for at least 6 months, with no more than 60% overall clinical success. Furthermore, mycobacterial antibiotic resistance is increasing worldwide, urging the need to develop novel classes of antimicrobial drugs. One potential and interesting alternative strategy is the use of antimicrobial peptides (AMP). These are present in almost all living organisms as part of their immune system, acting as a first barrier against invading pathogens. In this context, we investigated the effect of several lactoferrin-derived AMP against M. avium. Short peptide sequences from both human and bovine lactoferricins, namely, hLFcin1-11 and LFcin17-30, as well as variants obtained by specific amino acid substitutions, were evaluated. All tested peptides significantly inhibited the axenic growth of M. avium, the bovine peptides being more active than the human. Arginine residues were found to be crucial for the display of antimycobacterial activity, whereas the all-d-amino-acid analogue of the bovine sequence displayed the highest mycobactericidal activity. These findings reveal the promising potential of lactoferricins against mycobacteria, thus opening the way for further research on their development and use as a new weapon against mycobacterial infections. PMID:24709266