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Sample records for diminish bacterial clearance

  1. Air pollution particles diminish bacterial clearance in the primed lungs of mice

    SciTech Connect

    Sigaud, Samuel; Goldsmith, Carroll-Ann W.; Zhou Hongwei; Yang Zhiping; Fedulov, Alexey; Imrich, Amy; Kobzik, Lester

    2007-08-15

    Epidemiological studies reveal increased incidence of lung infection when air pollution particle levels are increased. We postulate that one risk factor for bacterial pneumonia, prior viral infection, can prime the lung for greater deleterious effects of particles via the interferon-gamma (IFN-{gamma}) characteristic of successful host anti-viral responses. To test this postulate, we developed a mouse model in which mice were treated with {gamma}-interferon aerosol, followed by exposure to concentrated ambient particles (CAPs) collected from urban air. The mice were then infected with Streptococcus pneumoniae and the effect of these treatments on the lung's innate immune response was evaluated. The combination of IFN-{gamma} priming and CAPs exposure enhanced lung inflammation, manifest as increased polymorphonuclear granulocyte (PMN) recruitment to the lung, and elevated expression of pro-inflammatory cytokine mRNAs. Combined priming and CAPs exposure resulted in impaired pulmonary bacterial clearance, as well as increased oxidant production and diminished bacterial uptake by alveolar macrophages (AMs) and PMNs. The data suggest that priming and CAPs exposure lead to an inflamed alveolar milieu where oxidant stress causes loss of antibacterial functions in AMs and recruited PMNs. The model reported here will allow further analysis of priming and CAPs exposure on lung sensitivity to infection.

  2. Autophagic clearance of bacterial pathogens: molecular recognition of intracellular microorganisms

    PubMed Central

    Mansilla Pareja, Maria Eugenia; Colombo, Maria I.

    2013-01-01

    Autophagy is involved in several physiological and pathological processes. One of the key roles of the autophagic pathway is to participate in the first line of defense against the invasion of pathogens, as part of the innate immune response. Targeting of intracellular bacteria by the autophagic machinery, either in the cytoplasm or within vacuolar compartments, helps to control bacterial proliferation in the host cell, controlling also the spreading of the infection. In this review we will describe the means used by diverse bacterial pathogens to survive intracellularly and how they are recognized by the autophagic molecular machinery, as well as the mechanisms used to avoid autophagic clearance. PMID:24137567

  3. Impaired cytokine expression, neutrophil infiltration and bacterial clearance in response to urinary tract infection in diabetic mice

    PubMed Central

    Ozer, Ahmet; Altuntas, Cengiz Z.; Bicer, Fuat; Izgi, Kenan; Hultgren, Scott J.; Liu, Guiming; Daneshgari, Firouz

    2015-01-01

    Diabetic patients have increased susceptibility to infections, and urinary tract infections (UTI) are the most common type in women with diabetes mellitus. Knowledge of bacterial clearance effectiveness following UTI in diabetics is sparse. In this study, the effects of diabetes on bacterial clearance efficiency and components of the innate immune system in response to UTI in a murine model were investigated. Streptozotocin-induced diabetic and control female C57BL/6J mice were infected with uropathogenic Escherichia coli, and bacterial load, expression of chemokines, and neutrophil infiltration in the bladder over time were investigated. Expression levels of histone deacetylases were also measured to address a potential mechanism underlying the phenotype. Bacterial clearance during UTI was significantly prolonged in diabetic mice relative to controls. Neutrophil infiltration in bladder tissue and urine, and both mRNA and protein expression of chemokines MIP-2, KC, MCP-1 and IL-6 in bladder tissue were diminished at early time points after infection in diabetic mice relative to controls. In addition, mRNA levels of histone deacetylases 1–5 were increased in diabetic mice. This is the first study to show an association of impaired bacterial clearance in diabetic mice with suppression of UTI-induced chemokine expression and neutrophil infiltration in the bladder. PMID:25663347

  4. Impaired cytokine expression, neutrophil infiltration and bacterial clearance in response to urinary tract infection in diabetic mice.

    PubMed

    Ozer, Ahmet; Altuntas, Cengiz Z; Bicer, Fuat; Izgi, Kenan; Hultgren, Scott J; Liu, Guiming; Daneshgari, Firouz

    2015-04-01

    Diabetic patients have increased susceptibility to infections, and urinary tract infections (UTI) are the most common type in women with diabetes mellitus. Knowledge of bacterial clearance effectiveness following UTI in diabetics is sparse. In this study, the effects of diabetes on bacterial clearance efficiency and components of the innate immune system in response to UTI in a murine model were investigated. Streptozotocin-induced diabetic and control female C57BL/6J mice were infected with uropathogenic Escherichia coli, and bacterial load, expression of chemokines, and neutrophil infiltration in the bladder over time were investigated. Expression levels of histone deacetylases were also measured to address a potential mechanism underlying the phenotype. Bacterial clearance during UTI was significantly prolonged in diabetic mice relative to controls. Neutrophil infiltration in bladder tissue and urine, and both mRNA and protein expression of chemokines MIP-2, KC, MCP-1 and IL-6 in bladder tissue were diminished at early time points after infection in diabetic mice relative to controls. In addition, mRNA levels of histone deacetylases 1-5 were increased in diabetic mice. This is the first study to show an association of impaired bacterial clearance in diabetic mice with suppression of UTI-induced chemokine expression and neutrophil infiltration in the bladder. PMID:25663347

  5. Hyperglycemia impedes lung bacterial clearance in a murine model of cystic fibrosis-related diabetes

    PubMed Central

    Hunt, William R.; Zughaier, Susu M.; Guentert, Dana E.; Shenep, Melissa A.; Koval, Michael; McCarty, Nael A.

    2013-01-01

    Cystic fibrosis-related diabetes (CFRD) is the most common comorbidity associated with cystic fibrosis (CF), impacting more than half of patients over age 30. CFRD is clinically significant, portending accelerated decline in lung function, more frequent pulmonary exacerbations, and increased mortality. Despite the profound morbidity associated with CFRD, little is known about the underlying CFRD-related pulmonary pathology. Our aim was to develop a murine model of CFRD to explore the hypothesis that elevated glucose in CFRD is associated with reduced lung bacterial clearance. A diabetic phenotype was induced in gut-corrected CF transmembrane conductance regulator (CFTR) knockout mice (CFKO) and their CFTR-expressing wild-type littermates (WT) utilizing streptozotocin. Mice were subsequently challenged with an intratracheal inoculation of Pseudomonas aeruginosa (PAO1) (75 μl of 1–5 × 106 cfu/ml) for 18 h. Bronchoalveolar lavage fluid was collected for glucose concentration and cell counts. A portion of the lung was homogenized and cultured as a measure of the remaining viable PAO1 inoculum. Diabetic mice had increased airway glucose compared with nondiabetic mice. The ability to clear bacteria from the lung was significantly reduced in diabetic WT mice and control CFKO mice. Critically, bacterial clearance by diabetic CFKO mice was significantly more diminished compared with nondiabetic CFKO mice, despite an even more robust recruitment of neutrophils to the airways. This finding that CFRD mice boast an exaggerated, but less effective, inflammatory cell response to intratracheal PAO1 challenge presents a novel and useful murine model to help identify therapeutic strategies that promote bacterial clearance in CFRD. PMID:24097557

  6. Hyperglycemia impedes lung bacterial clearance in a murine model of cystic fibrosis-related diabetes.

    PubMed

    Hunt, William R; Zughaier, Susu M; Guentert, Dana E; Shenep, Melissa A; Koval, Michael; McCarty, Nael A; Hansen, Jason M

    2014-01-01

    Cystic fibrosis-related diabetes (CFRD) is the most common comorbidity associated with cystic fibrosis (CF), impacting more than half of patients over age 30. CFRD is clinically significant, portending accelerated decline in lung function, more frequent pulmonary exacerbations, and increased mortality. Despite the profound morbidity associated with CFRD, little is known about the underlying CFRD-related pulmonary pathology. Our aim was to develop a murine model of CFRD to explore the hypothesis that elevated glucose in CFRD is associated with reduced lung bacterial clearance. A diabetic phenotype was induced in gut-corrected CF transmembrane conductance regulator (CFTR) knockout mice (CFKO) and their CFTR-expressing wild-type littermates (WT) utilizing streptozotocin. Mice were subsequently challenged with an intratracheal inoculation of Pseudomonas aeruginosa (PAO1) (75 μl of 1-5 × 10(6) cfu/ml) for 18 h. Bronchoalveolar lavage fluid was collected for glucose concentration and cell counts. A portion of the lung was homogenized and cultured as a measure of the remaining viable PAO1 inoculum. Diabetic mice had increased airway glucose compared with nondiabetic mice. The ability to clear bacteria from the lung was significantly reduced in diabetic WT mice and control CFKO mice. Critically, bacterial clearance by diabetic CFKO mice was significantly more diminished compared with nondiabetic CFKO mice, despite an even more robust recruitment of neutrophils to the airways. This finding that CFRD mice boast an exaggerated, but less effective, inflammatory cell response to intratracheal PAO1 challenge presents a novel and useful murine model to help identify therapeutic strategies that promote bacterial clearance in CFRD. PMID:24097557

  7. Discovery of bacterial NAD⁺-dependent DNA ligase inhibitors: improvements in clearance of adenosine series.

    PubMed

    Stokes, Suzanne S; Gowravaram, Madhusudhan; Huynh, Hoan; Lu, Min; Mullen, George B; Chen, Brendan; Albert, Robert; O'Shea, Thomas J; Rooney, Michael T; Hu, Haiqing; Newman, Joseph V; Mills, Scott D

    2012-01-01

    Optimization of clearance of adenosine inhibitors of bacterial NAD(+)-dependent DNA ligase is discussed. To reduce Cytochrome P-450-mediated metabolic clearance, many strategies were explored; however, most modifications resulted in compounds with reduced antibacterial activity and/or unchanged total clearance. The alkyl side chains of the 2-cycloalkoxyadenosines were fluorinated, and compounds with moderate antibacterial activity and favorable pharmacokinetic properties in rat and dog were identified. PMID:22154350

  8. Effects of zinc oxide nanoparticles on Kupffer cell phagosomal motility, bacterial clearance, and liver function

    PubMed Central

    Watson, Christa Y; Molina, Ramon M; Louzada, Andressa; Murdaugh, Kimberly M; Donaghey, Thomas C; Brain, Joseph D

    2015-01-01

    Background Zinc oxide engineered nanoparticles (ZnO ENPs) have potential as nanomedicines due to their inherent properties. Studies have described their pulmonary impact, but less is known about the consequences of ZnO ENP interactions with the liver. This study was designed to describe the effects of ZnO ENPs on the liver and Kupffer cells after intravenous (IV) administration. Materials and methods First, pharmacokinetic studies were conducted to determine the tissue distribution of neutron-activated 65ZnO ENPs post-IV injection in Wistar Han rats. Then, a noninvasive in vivo method to assess Kupffer cell phagosomal motility was employed using ferromagnetic iron particles and magnetometry. We also examined whether prior IV injection of ZnO ENPs altered Kupffer cell bactericidal activity on circulating Pseudomonas aeruginosa. Serum and liver tissues were collected to assess liver-injury biomarkers and histological changes, respectively. Results We found that the liver was the major site of initial uptake of 65ZnO ENPs. There was a time-dependent decrease in tissue levels of 65Zn in all organs examined, refecting particle dissolution. In vivo magnetometry showed a time-dependent and transient reduction in Kupffer cell phagosomal motility. Animals challenged with P. aeruginosa 24 hours post-ZnO ENP injection showed an initial (30 minutes) delay in vascular bacterial clearance. However, by 4 hours, IV-injected bacteria were cleared from the blood, liver, spleen, lungs, and kidneys. Seven days post-ZnO ENP injection, creatine phosphokinase and aspartate aminotransferase levels in serum were significantly increased. Histological evidence of hepatocyte damage and marginated neutrophils were observed in the liver. Conclusion Administration of ZnO ENPs transiently inhibited Kupffer cell phagosomal motility and later induced hepatocyte injury, but did not alter bacterial clearance from the blood or killing in the liver, spleen, lungs, or kidneys. Our data show that

  9. Increased Myeloid Cell Production and Lung Bacterial Clearance in Mice Exposed to Cigarette Smoke.

    PubMed

    Basilico, Paola; Cremona, Tiziana P; Oevermann, Anna; Piersigilli, Alessandra; Benarafa, Charaf

    2016-03-01

    Pneumonia is a leading cause of hospitalization in patients with chronic obstructive pulmonary disease (COPD). Although most patients with COPD are smokers, the effects of cigarette smoke exposure on clearance of lung bacterial pathogens and on immune and inflammatory responses are incompletely defined. Here, clearance of Streptococcus pneumoniae and Pseudomonas aeruginosa and associated immune responses were examined in mice exposed to cigarette smoke or after smoking cessation. Mice exposed to cigarette smoke for 6 weeks or 4 months demonstrated decreased lung bacterial burden compared with air-exposed mice when infected 16 to 24 hours after exposure. When infection was performed after smoke cessation, bacterial clearance kinetics of mice previously exposed to smoke reversed to levels comparable to those of control mice, suggesting that the observed defects were not dependent on adaptive immunological memory to bacterial determinants found in smoke. Comparing cytokine levels and myeloid cell production before infection in mice exposed to cigarette smoke with mice never exposed or after smoke cessation revealed that reduced bacterial burden was most strongly associated with higher levels of IL-1β and granulocyte-macrophage colony-stimulating factor in the lungs and with increased neutrophil reserve and monocyte turnover in the bone marrow. Using Serpinb1a-deficient mice with reduced neutrophil numbers and treatment with granulocyte colony-stimulating factor showed that increased neutrophil numbers contribute only in part to the effect of smoke on infection. Our findings indicate that cigarette smoke induces a temporary and reversible increase in clearance of lung pathogens, which correlates with local inflammation and increased myeloid cell output from the bone marrow. PMID:26273827

  10. Radiolabel ratio method for measuring pulmonary clearance of intratracheal bacterial challenges

    SciTech Connect

    LaForce, F.M.; Boose, D.S.

    1988-02-01

    Calculation of bacterial clearance is a fundamental step in any study of in situ lung antibacterial defenses. A method is described whereby about 85% of a radiolabeled bacterial inoculum was consistently introduced into the bronchopulmonary tree of a mouse by the intratracheal route. Mice were then killed 1 and 4 hours later; their lungs were removed aseptically and homogenized, and viable bacteria and radiolabel counts were determined. Radiolabel counts fell slowly, and more than 80% of the original radiolabel was still present in homogenized lung samples from animals sacrificed 4 hours after challenge. Bacteria/isotope ratios for the bacterial inoculum and homogenized lung samples from animals sacrificed immediately after challenge were very similar. Bacterial clearance values were the same whether computed from bacterial counts alone or according to a radiolabel ratio method whereby the change in the bacteria/isotope ratio in ground lung aliquots was divided by a similar ratio from bacteria used to inoculate animals. Some contamination resulted from oral streptococci being swept into the bronchopulmonary free during the aspiration process. This contamination was not a problem when penicillin was incorporated into the agar and penicillin-resistant strains were used for the bacterial challenges.

  11. A PPARγ AGONIST ENHANCES BACTERIAL CLEARANCE THROUGH NEUTROPHIL EXTRACELLULAR TRAP FORMATION AND IMPROVES SURVIVAL IN SEPSIS.

    PubMed

    Araújo, Cláudia V; Campbell, Clarissa; Gonçalves-de-Albuquerque, Cassiano F; Molinaro, Raphael; Cody, Mark J; Yost, Christian C; Bozza, Patricia T; Zimmerman, Guy A; Weyrich, Andrew S; Castro-Faria-Neto, Hugo C; Silva, Adriana R

    2016-04-01

    Dysregulation of the inflammatory response against infection contributes to mortality in sepsis. Inflammation provides critical host defense, but it can cause tissue damage, multiple organ failure, and death. Because the nuclear transcription factor peroxisome proliferator-activated receptor γ (PPARγ) exhibits therapeutic potential, we characterized the role of PPARγ in sepsis. We analyzed severity of clinical signs, survival rates, cytokine production, leukocyte influx, and bacterial clearance in a cecal ligation and puncture (CLP) model of sepsis in Swiss mice. The PPARγ agonist rosiglitazone treatment improved clinical status and mortality, while increasing IL-10 production and decreasing TNF-α and IL-6 levels, and peritoneal neutrophil accumulation 24 h after CLP. We noted increased bacterial killing in rosiglitazone treated mice, correlated with increased generation of reactive oxygen species. Polymorphonuclear leukocytes (PMN) incubated with LPS or Escherichia coli and rosiglitazone increased peritoneal neutrophil extracellular trap (NET)-mediated bacterial killing, an effect reversed by the PPARγ antagonist (GW 9662) treatment. Rosiglitazone also enhanced the release of histones by PMN, a surrogate marker of NET formation, effect abolished by GW 9662. Rosiglitazone modulated the inflammatory response and increased bacterial clearance through PPARγ activation and NET formation, combining immunomodulatory and host-dependent anti-bacterial effects and, therefore, warrants further study as a potential therapeutic agent in sepsis. PMID:26618986

  12. New heparinizable modified poly(carbonate urethane) surfaces diminishing bacterial colonization.

    PubMed

    De Nardo, Luigi; Farè, Silvia; Di Matteo, Valentina; Cipolla, Eliana; Saino, Enrica; Visai, Livia; Speziale, Pietro; Tanzi, Maria Cristina

    2007-11-01

    Percutaneous devices are extensively used in modern medicine therapies, even in long term applications. Complications from their use, related to bacterial colonization and/or to materials thrombogenicity, may result in a significant morbidity and mortality incidence. In this study, a novel polycarbonate-urethane (PCU), incorporating a tailor-made diamino-diamide-diol (PIME) showing the ability to bind heparin at physiological pH, was compared to commercial medical-grade PCUs (Carbothane and Bionate). Mechanical and thermal properties were evaluated by tensile tests, dynamic mechanical analysis and differential scanning calorimetry. The presence of a low amount of PIME chain extender in Bionate polyurethanes (Bionate-PIME) slightly affects the mechanical properties, remaining however comparable with the medical grade PCUs used for the fabrication of cardiovascular devices. To verify thereof heparin surface adsorbed in disfavouring bacterial colonization, heparinized Bionate-PIME was tested for bacterial adhesion, using Bionate and Carbothane as reference. In vitro bacterial interaction tests were performed with the strains mainly involved in the pathogenesis of device-related infections (S. epidermidis and S. aureus). MTT tests and SEM observations showed a decrease in colonization of the different strains on the heparinized Bionate-PIME surfaces, confirming that preadsorbed heparin plays a role in mediating the biomaterial surface/bacterial cells interactions. PMID:17665117

  13. Lipopolysaccharide clearance, bacterial clearance, and systemic inflammatory responses are regulated by cell type-specific functions of TLR4 during sepsis.

    PubMed

    Deng, Meihong; Scott, Melanie J; Loughran, Patricia; Gibson, Gregory; Sodhi, Chhinder; Watkins, Simon; Hackam, David; Billiar, Timothy R

    2013-05-15

    The morbidity associated with bacterial sepsis is the result of host immune responses to pathogens, which are dependent on pathogen recognition by pattern recognition receptors, such as TLR4. TLR4 is expressed on a range of cell types, yet the mechanisms by which cell-specific functions of TLR4 lead to an integrated sepsis response are poorly understood. To address this, we generated mice in which TLR4 was specifically deleted from myeloid cells (LysMTLR4KO) or hepatocytes (HCTLR4KO) and then determined survival, bacterial counts, host inflammatory responses, and organ injury in a model of cecal ligation and puncture (CLP), with or without antibiotics. LysM-TLR4 was required for phagocytosis and efficient bacterial clearance in the absence of antibiotics. Survival, the magnitude of the systemic and local inflammatory responses, and liver damage were associated with bacterial levels. HCTLR4 was required for efficient LPS clearance from the circulation, and deletion of HCTLR4 was associated with enhanced macrophage phagocytosis, lower bacterial levels, and improved survival in CLP without antibiotics. Antibiotic administration during CLP revealed an important role for hepatocyte LPS clearance in limiting sepsis-induced inflammation and organ injury. Our work defines cell type-selective roles for TLR4 in coordinating complex immune responses to bacterial sepsis and suggests that future strategies for modulating microbial molecule recognition should account for varying roles of pattern recognition receptors in multiple cell populations. PMID:23562812

  14. Hyperglycemia Impairs Neutrophil-Mediated Bacterial Clearance in Mice Infected with the Lyme Disease Pathogen

    PubMed Central

    Javid, Ashkan; Zlotnikov, Nataliya; Pětrošová, Helena; Tang, Tian Tian; Zhang, Yang; Bansal, Anil K.; Ebady, Rhodaba; Parikh, Maitry; Ahmed, Mijhgan; Sun, Chunxiang; Newbigging, Susan; Kim, Yae Ram; Santana Sosa, Marianna; Glogauer, Michael

    2016-01-01

    Insulin-insufficient type 1 diabetes is associated with attenuated bactericidal function of neutrophils, which are key mediators of innate immune responses to microbes as well as pathological inflammatory processes. Neutrophils are central to immune responses to the Lyme pathogen Borrelia burgdorferi. The effect of hyperglycemia on host susceptibility to and outcomes of B. burgdorferi infection has not been examined. The present study investigated the impact of sustained obesity-independent hyperglycemia in mice on bacterial clearance, inflammatory pathology and neutrophil responses to B. burgdorferi. Hyperglycemia was associated with reduced arthritis incidence but more widespread tissue colonization and reduced clearance of bacterial DNA in multiple tissues including brain, heart, liver, lung and knee joint. B. burgdorferi uptake and killing were impaired in neutrophils isolated from hyperglycemic mice. Thus, attenuated neutrophil function in insulin-insufficient hyperglycemia was associated with reduced B. burgdorferi clearance in target organs. These data suggest that investigating the effects of comorbid conditions such as diabetes on outcomes of B. burgdorferi infections in humans may be warranted. PMID:27340827

  15. Hyperglycemia Impairs Neutrophil-Mediated Bacterial Clearance in Mice Infected with the Lyme Disease Pathogen.

    PubMed

    Javid, Ashkan; Zlotnikov, Nataliya; Pětrošová, Helena; Tang, Tian Tian; Zhang, Yang; Bansal, Anil K; Ebady, Rhodaba; Parikh, Maitry; Ahmed, Mijhgan; Sun, Chunxiang; Newbigging, Susan; Kim, Yae Ram; Santana Sosa, Marianna; Glogauer, Michael; Moriarty, Tara J

    2016-01-01

    Insulin-insufficient type 1 diabetes is associated with attenuated bactericidal function of neutrophils, which are key mediators of innate immune responses to microbes as well as pathological inflammatory processes. Neutrophils are central to immune responses to the Lyme pathogen Borrelia burgdorferi. The effect of hyperglycemia on host susceptibility to and outcomes of B. burgdorferi infection has not been examined. The present study investigated the impact of sustained obesity-independent hyperglycemia in mice on bacterial clearance, inflammatory pathology and neutrophil responses to B. burgdorferi. Hyperglycemia was associated with reduced arthritis incidence but more widespread tissue colonization and reduced clearance of bacterial DNA in multiple tissues including brain, heart, liver, lung and knee joint. B. burgdorferi uptake and killing were impaired in neutrophils isolated from hyperglycemic mice. Thus, attenuated neutrophil function in insulin-insufficient hyperglycemia was associated with reduced B. burgdorferi clearance in target organs. These data suggest that investigating the effects of comorbid conditions such as diabetes on outcomes of B. burgdorferi infections in humans may be warranted. PMID:27340827

  16. Thyroid Hormone Enhances Nitric Oxide-Mediated Bacterial Clearance and Promotes Survival after Meningococcal Infection

    PubMed Central

    Wang, Xiao; Altenbacher, Georg; Hagner, Matthias; Berglund, Pernilla; Gao, Yumin; Lu, Ting; Jonsson, Ann-Beth; Sjölinder, Hong

    2012-01-01

    Euthyroid sick syndrome characterized by reduced levels of thyroid hormones (THs) is observed in patients with meningococcal shock. It has been found that the level of THs reflects disease severity and is predictive for mortality. The present study was conducted to investigate the impact of THs on host defense during meningococcal infection. We found that supplementation of thyroxine to mice infected with Neisseria meningitidis enhanced bacterial clearance, attenuated the inflammatory responses and promoted survival. In vitro studies with macrophages revealed that THs enhanced bacteria-cell interaction and intracellular killing of meningococci by stimulating inducible nitric oxide synthase (iNos)-mediated NO production. TH treatment did not activate expression of TH receptors in macrophages. Instead, the observed TH-directed actions were mediated through nongenomic pathways involving the protein kinases PI3K and ERK1/2 and initiated at the membrane receptor integrin αvβ3. Inhibition of nongenomic TH signaling prevented iNos induction, NO production and subsequent intracellular bacterial killing by macrophages. These data demonstrate a beneficial role of THs in macrophage-mediated N. meningitidis clearance. TH replacement might be a novel option to control meningococcal septicemia. PMID:22844479

  17. Activation of Pattern Recognition Receptors Upregulates Metallothioneins, Thereby Increasing Intracellular Accumulation of Zinc, Autophagy, and Bacterial Clearance by Macrophages

    PubMed Central

    Lahiri, Amit; Abraham, Clara

    2014-01-01

    Background & Aims Continuous stimulation of pattern recognition receptors (PRRs), including nucleotide-binding oligomerization domain-2 (NOD2) (variants in NOD2 have been associated with Crohn's disease), alters the phenotype of myeloid-derived cells, reducing production of inflammatory cytokines and increasing clearance of microbes. We investigated the mechanisms by which microbial clearance increases in macrophages under these conditions. METHODS Monocytes were purified from human peripheral blood mononuclear cells and differentiated to monocyte-derived macrophages (MDMs). We also isolated human intestinal macrophages. Bacterial clearance by MDMs was assessed in gentamicin protection assays. Effects of intracellular zinc and autophagy were measured by flow cytometry, immunoblot, reverse transcription PCR, and microscopy experiments. Small interfering RNAs were used to knock down specific proteins in MDMs. NOD2–/– and C57BL/6J mice, maintained in a specific pathogen-free facility, were given antibiotics, muramyl dipeptide (to stimulate NOD2), or dextran sodium sulfate; intestinal lamina propria cells were collected and analyzed. RESULTS Chronic stimulation of human MDMs through NOD2 upregulated the expression of multiple genes encoding metallothioneins, which bind and regulate levels of intracellular zinc. Intestinal myeloid-derived cells are continually stimulated through PRRs; metallothionein expression was upregulated in human and mouse intestinal myeloid-derived cells. Continuous stimulation of NOD2 increased levels of intracellular zinc, thereby increasing autophagy and bacterial clearance. The metal-regulatory transcription factor-1 (MTF-1) was required for regulation of metallothionein genes in human MDMs. Knockdown of MTF-1 did not affect baseline clearance of bacteria by MDMs. However, the increase in intracellular zinc, autophagy, and bacterial clearance observed with continuous NOD2 stimulation was impaired in MDMs upon MTF-1 knockdown. Addition of

  18. CAP-D3 Promotes Bacterial Clearance in Human Intestinal Epithelial Cells by Repressing Expression of Amino Acid Transporters

    PubMed Central

    Kemp, Jacqueline R.; Nickerson, Kourtney P.; Deutschman, Emily; Kim, Yeojung; West, Gail; Sadler, Tammy; Stylianou, Eleni; Krokowski, Dawid; Hatzoglou, Maria; de la Motte, Carol; Rubin, Brian P.; Fiocchi, Claudio

    2015-01-01

    BACKGROUND & AIMS Defects in colonic epithelial barrier defenses are associated with ulcerative colitis (UC). The proteins that regulate bacterial clearance in the colonic epithelium have not been completely identified. The chromosome-associated protein D3 (dCAP-D3), regulates responses to bacterial infection. We examined whether CAP-D3 promotes bacterial clearance in human colonic epithelium. METHODS Clearance of Salmonella or adherent-invasive Escherichia coli LF82 was assessed by gentamycin protection assays in HT-29 and Caco-2 cells expressing small hairpin RNAs against CAP-D3. We used immunoblot assays to measure levels of CAP-D3 in colonic epithelial cells from patients with UC and healthy individuals (controls). RNA sequencing identified genes activated by CAP-D3. We analyzed the roles of CAP-D3 target genes in bacterial clearance using gentamycin protection and immunofluorescence assays and studies with pharmacologic inhibitors. RESULTS CAP-D3 expression was reduced in colonic epithelial cells from patients with active UC. Reduced CAP-D3 expression decreased autophagy and impaired intracellular bacterial clearance by HT-29 and Caco-2 colonic epithelial cells. Lower levels of CAP-D3 increased transcription of genes encoding SLC7A5 and SLC3A2, whose products heterodimerize to form an amino acid transporter in HT-29 cells following bacterial infection; levels of SLC7A5–SLC3A2 were increased in tissues from patients with UC, compared with controls. Reduced CAP-D3 in HT-29 cells resulted in earlier recruitment of SLC7A5 to Salmonella-containing vacuoles, increased activity of mTORC1, and increased survival of bacteria. Inhibition of SLC7A5–SLC3A2 or mTORC1 activity rescued the bacterial clearance defects of CAP-D3– deficient cells. CONCLUSIONS CAP-D3 downregulates transcription of genes that encode amino acid transporters (SLC7A5 and SLC3A2) to promote bacterial autophagy by colon epithelial cells. Levels of CAP-D3 protein are reduced in patients with

  19. Interleukin-33 facilitates neutrophil recruitment and bacterial clearance in S. aureus-caused peritonitis.

    PubMed

    Lan, Fang; Yuan, Baohong; Liu, Tao; Luo, Xiaochun; Huang, Ping; Liu, Yunjun; Dai, Liangcheng; Yin, Hui

    2016-04-01

    Interleukin (IL)-33, a newly recognized member of IL-1 family of cytokines, plays an important role in polarizing Th2-associated immunity. Recently growing evidence indicates that IL-33 also represents a crucial mediator of antimicrobial infection. In this study, we investigated the effect of IL-33 on antibacterial response using an acute Staphylococcus aureus peritoneal infection model. Our results showed that IL-33 administration induced a rapid bacterial clearance and markedly reduced the S. aureus infection-related mortality. IL-33-treated mice displayed increased neutrophil influx into the focus of infection and higher concentrations of chemokine CXCL2 in the peritoneum than untreated mice. The beneficial effect of IL-33 priming was related to reversal of the S. aureus-induced reduction of CXCR2 expression on the surface of neutrophils. Furthermore, conditioning of neutrophils by IL-33 led to the enhancement of complement receptor 3 expression induced by S. aureus, which in turn facilitates the phagocytosis of opsonized S. aureus. Finally, neutrophils primed by IL-33 upregulated the production of reactive oxygen species and the subsequent killing activity for S. aureus. All together, these findings suggest that IL-33, through regulating multiple steps of neutrophil-mediated bactericidal function, provides a profound effect in host antimicrobial defense response. PMID:26991049

  20. Helminth-Induced Interleukin-4 Abrogates Invariant Natural Killer T Cell Activation-Associated Clearance of Bacterial Infection

    PubMed Central

    Hsieh, Yi-Ju; Fu, Chi-Ling

    2014-01-01

    Helminth infections affect 1 billion people worldwide and render these individuals susceptible to bacterial coinfection through incompletely understood mechanisms. This includes urinary tract coinfection by bacteria and Schistosoma haematobium worms, the etiologic agent of urogenital schistosomiasis. To study the mechanisms of S. haematobium-bacterial urinary tract coinfections, we combined the first tractable model of urogenital schistosomiasis with an established mouse model of bacterial urinary tract infection (UTI). A single bladder exposure to S. haematobium eggs triggers interleukin-4 (IL-4) production and makes BALB/c mice susceptible to bacterial UTI when they are otherwise resistant. Ablation of IL-4 receptor alpha (IL-4Rα) signaling restored the baseline resistance of BALB/c mice to bacterial UTI despite prior exposure to S. haematobium eggs. Interestingly, numbers of NKT cells were decreased in coexposed versus bacterially monoinfected bladders. Given that schistosome-induced, non-natural killer T (NKT) cell leukocyte infiltration may dilute NKT cell numbers in the bladders of coexposed mice without exerting a specific functional effect on these cells, we next examined NKT cell biology on a per-cell basis. Invariant NKT (iNKT) cells from coexposed mice expressed less gamma interferon (IFN-γ) per cell than did those from mice with UTI alone. Moreover, coexposure resulted in lower CD1d expression in bladder antigen-presenting cells (APC) than did bacterial UTI alone in an IL-4Rα-dependent fashion. Finally, coexposed mice were protected from prolonged bacterial infection by administration of α-galactosylceramide, an iNKT cell agonist. Our findings point to a previously unappreciated role for helminth-induced IL-4 in impairment of iNKT cell-mediated clearance of bacterial coexposure. PMID:24643536

  1. Oral application of bacterial lysate in infancy diminishes the prevalence of atopic dermatitis in children at risk for atopy.

    PubMed

    Lau, S

    2014-06-01

    Numerous interventions such as avoidance of food allergens, prolonged breast feeding and supplementation of pro-and/or prebiotics have been tried as primary prevention of atopic dermatitis. Recent data suggest that prevention of infantile eczema is possible in a subgroup of children by feeding bacterial lysates early in life. Bacterial lysates of Escherichia coli and Enterococcus faecalis were found to impair allergic immune responses in rats. An interventional trial in 606 infants at risk for atopy showed a reduction of atopic dermatitis at the end of the treatment phase (month 2 until month 7) of 50% in a subgroup of children with single heredity for atopy. This was even more pronounced in the group of children with paternal heredity for atopy. This effect was still seen at age 1 year. There was no effect on food sensitisation. In conclusion, an immune modulation in terms of prevention of atopic dermatitis in infancy if single atopic family history is present seems to be possible by feeding bacterial lysates early in life. PMID:23886978

  2. Bacterial clearance is improved in septic mice by platelet-activating factor-acetylhydrolase (PAF-AH) administration.

    PubMed

    Teixeira-da-Cunha, Mariana G A; Gomes, Rachel N; Roehrs, Nathassia; Bozza, Fernando A; Prescott, Stephen M; Stafforini, Diana; Zimmerman, Guy A; Bozza, Patricia T; Castro-Faria-Neto, Hugo C

    2013-01-01

    Current evidence indicates that dysregulation of the host inflammatory response to infectious agents is central to the mortality of patients with sepsis. Strategies to block inflammatory mediators such as PAF have been investigated as adjuvant therapies for sepsis. PAF-AH, the enzyme responsible for PAF degradation, showed positive results in pre-clinical studies and phase II clinical trials, but the results of a phase III study were disappointing. In this study, we investigated the potential protective mechanism of PAF-AH in sepsis using the murine model of cecal ligation and puncture (CLP). Treatment with rPAF-AH increased peritoneal fluid levels of the anti-inflammatory mediators MCP-1/CCL2 after CLP. The numbers of bacteria (CFU) in the peritoneal cavity were decreased in the rPAF-AH-treated group, indicating more efficient bacterial clearance after rPAF-AH treatment. Interestingly, we observed increased levels of nitric oxide (NO) after PAF-AH administration, and rPAF-AH treatment did not decrease CFU numbers either in iNOS-deficient mice or in CCR2-deficient mice. We concluded that administration of exogenous rPAF-AH reduced inflammatory injury, altered cytokine levels and favored bacterial clearance with a clear impact on mortality through modulation of MCP-1/CCL2 and NO levels in a clinically relevant sepsis model. PMID:24069320

  3. Bone Marrow–Derived Mesenchymal Stem Cells Enhance Bacterial Clearance and Preserve Bioprosthetic Integrity in a Model of Mesh Infection

    PubMed Central

    Criman, Erik T.; Kurata, Wendy E.; Matsumoto, Karen W.; Aubin, Harry T.; Campbell, Carmen E.

    2016-01-01

    Background: The reported incidence of mesh infection in contaminated operative fields is as high as 30% regardless of the material used. Recently, mesenchymal stem cells (MSCs) have been shown to possess favorable immunomodulatory properties and improve tissue incorporation when seeded onto bioprosthetics. The aim of this study was to evaluate whether seeding noncrosslinked bovine pericardium (Veritas Collagen Matrix) with allogeneic bone marrow–derived MSCs improves infection resistance in vivo after inoculation with Escherichia coli (E. coli). Methods: Rat bone marrow–derived MSCs at passage 3 were seeded onto bovine pericardium and cultured for 7 days before implantation. Additional rats (n = 24) were implanted subcutaneously with MSC-seeded or unseeded mesh and inoculated with 7 × 105 colony-forming units of E. coli or saline before wound closure (group 1, unseeded mesh/saline; group 2, unseeded mesh/E. coli; group 3, MSC-seeded mesh/E. coli; 8 rats per group). Meshes were explanted at 4 weeks and underwent microbiologic and histologic analyses. Results: MSC-seeded meshes inoculated with E. coli demonstrated superior bacterial clearance and preservation of mesh integrity compared with E. coli–inoculated unseeded meshes (87.5% versus 0% clearance; p = 0.001). Complete mesh degradation concurrent with abscess formation was observed in 100% of rats in the unseeded/E. coli group, which is in contrast to 12.5% of rats in the MSC-seeded/E. coli group. Histologic evaluation determined that remodeling characteristics of E. coli–inoculated MSC-seeded meshes were similar to those of uninfected meshes 4 weeks after implantation. Conclusions: Augmenting a bioprosthetic material with stem cells seems to markedly enhance resistance to bacterial infection in vivo and preserve mesh integrity. PMID:27482490

  4. Critical roles of sea cucumber C-type lectin in non-self recognition and bacterial clearance.

    PubMed

    Wei, Xiumei; Liu, Xiangquan; Yang, Jianmin; Wang, Sheng; Sun, Guohua; Yang, Jialong

    2015-08-01

    C-type lectin is one important pattern recognition receptor (PRR) that plays crucial roles in multiple immune responses. A C-type lectin from sea cucumber Apostichopus japonicus (AjCTL-1) was characterized in the present study. The amino acid sequence of AjCTL-1 shared high similarities with other C-type lectins from invertebrates and vertebrates. The C-type lectin domain (CTLD) of AjCTL-1 contained a Ca(2+)-binding site 2 and four conserved cysteine residues. AjCTL-1 mRNA expression patterns in tissues and after bacterial challenge were then analysed. Quantitative PCR revealed that AjCTL-1 mRNA was widely expressed in the tested tissues of healthy sea cucumber. The highest expression level occurred in gonad followed by body wall, coelomocytes, tentacle, intestinum and longitudinal muscle, and the lowest expression level was in respiratory tree. AjCTL-1 mRNA expression in coelomocytes was significantly induced by gram-negative Listonella anguillarum and gram-positive Micrococcus luteus, with different up-regulation patterns post-challenge. Recombinant AjCTL-1 exhibited the ability to bind peptidoglycan directly, agglutinate M. luteus, Staphylococcus aureus and Escherichia coli, in a Ca(2+)-dependant manner, and enhance the phagocytosis of coelomocytes against E. coli in vitro. The results indicated that AjCTL-1 could act as a PRR in Apostichopus japonicus and had critical roles in non-self recognition and bacterial clearance against invading microbes. PMID:26052017

  5. Hindlimb Suspension and SPE-Like Radiation Impairs Clearance of Bacterial Infections

    PubMed Central

    Li, Minghong; Holmes, Veronica; Zhou, Yu; Ni, Houping; Sanzari, Jenine K.; Kennedy, Ann R.; Weissman, Drew

    2014-01-01

    A major risk of extended space travel is the combined effects of weightlessness and radiation exposure on the immune system. In this study, we used the hindlimb suspension model of microgravity that includes the other space stressors, situational and confinement stress and alterations in food intake, and solar particle event (SPE)-like radiation to measure the combined effects on the ability to control bacterial infections. A massive increase in morbidity and decrease in the ability to control bacterial growth was observed using 2 different types of bacteria delivered by systemic and pulmonary routes in 3 different strains of mice. These data suggest that an astronaut exposed to a strong SPE during extended space travel is at increased risk for the development of infections that could potentially be severe and interfere with mission success and astronaut health. PMID:24454913

  6. miR-155 suppresses bacterial clearance in Pseudomonas aeruginosa-induced keratitis by targeting Rheb.

    PubMed

    Yang, Kun; Wu, Minhao; Li, Meiyu; Li, Dandan; Peng, Anping; Nie, Xinxin; Sun, Mingxia; Wang, Jinli; Wu, Yongjian; Deng, Qiuchan; Zhu, Min; Chen, Kang; Yuan, Jin; Huang, Xi

    2014-07-01

    miR-155 (microRNA-155) is an important noncoding RNA in regulating host inflammatory responses. However, its regulatory role in ocular infection remains unclear. Our study first explored the function of miR-155 in Pseudomonas aeruginosa-induced keratitis, one of the most common sight-threatening ocular diseases. We found that miR-155 expression was enhanced in human and mouse corneas after P. aeruginosa infection and was mainly expressed in macrophages but not neutrophils. In vivo studies demonstrated that miR-155 knockout mice displayed more resistance to P. aeruginosa keratitis, with a higher inducible nitric oxide synthase level and a lower bacterial burden. More importantly, in vitro data indicated that miR-155 suppressed the macrophage-mediated bacterial phagocytosis and intracellular killing of P. aeruginosa by targeting Rheb (Ras homolog enriched in brain). To the best of our knowledge, this is the first study to explore the role of miR-155 in bacterial keratitis, which may provide a promising target for clinical treatment of P. aeruginosa keratitis and other infectious diseases. PMID:24403554

  7. Intermittent fasting promotes bacterial clearance and intestinal IgA production in Salmonella typhimurium-infected mice.

    PubMed

    Godínez-Victoria, M; Campos-Rodriguez, R; Rivera-Aguilar, V; Lara-Padilla, E; Pacheco-Yepez, J; Jarillo-Luna, R A; Drago-Serrano, M E

    2014-05-01

    The impact of intermittent fasting versus ad libitum feeding during Salmonella typhimurium infection was evaluated in terms of duodenum IgA levels, bacterial clearance and intestinal and extra-intestinal infection susceptibility. Mice that were intermittently fasted for 12 weeks or fed ad libitum were infected with S. typhimurium and assessed at 7 and 14 days post-infection. Next, we evaluated bacterial load in the faeces, Peyer's patches, spleen and liver by plate counting, as well as total and specific intestinal IgA and plasmatic corticosterone levels (by immunoenzymatic assay) and lamina propria IgA levels in plasma cells (by cytofluorometry). Polymeric immunoglobulin receptor, α- and J-chains, Pax-5 factor, pro-inflammatory cytokine (tumour necrosis factor-α and interferon-γ) and anti-inflammatory cytokine (transforming growth factor-β) mRNA levels were assessed in mucosal and liver samples (by real-time PCR). Compared with the infected ad libitum mice, the intermittently fasted infected animals had (1) lower intestinal and systemic bacterial loads; (2) higher SIgA and IgA plasma cell levels; (3) higher mRNA expression of most intestinal parameters; and (4) increased or decreased corticosterone levels on day 7 and 14 post-infection, respectively. No contribution of liver IgA was observed at the intestinal level. Apparently, the changes following metabolic stress induced by intermittent fasting during food deprivation days increased the resistance to S. typhimurium infection by triggering intestinal IgA production and presumably, pathogen elimination by phagocytic inflammatory cells. PMID:24612255

  8. Resolvin D4 stereoassignment and its novel actions in host protection and bacterial clearance

    PubMed Central

    Winkler, Jeremy W.; Orr, Sarah K.; Dalli, Jesmond; Cheng, Chien-Yee C.; Sanger, Julia M.; Chiang, Nan; Petasis, Nicos A.; Serhan, Charles N.

    2016-01-01

    Resolvins of the D-series are specialized pro-resolving lipid mediators that regulate cellular response by orchestrating resolution networks involved in host responses to injury and infection. Here, endogenous resolvin D4 was identified in human tissues and found to persist late into the resolution phase of acute murine Staphylococcus aureus infections. Completion of the first total synthesis of resolvin D4 established the absolute stereochemical configuration of RvD4 confirmed by matching with endogenous RvD4 from resolving exudates in dorsal pouch S. aureus infections. In vivo, RvD4 (ng/mouse) reduced neutrophilic infiltration (~40%) and enhanced uptake of apoptotic PMN (51%) by human dermal fibroblasts at concentrations as low as 0.1 nM. These results establish the complete stereochemistry of RvD4 as 4S,5R,17S-trihydroxydocosa-6E,8E,10Z,13Z,15E,19Z-hexaenoic acid and its novel pro-resolving actions in S. aureus infections as well as its potent ability to stimulate clearance of apoptotic cells by skin fibroblasts. PMID:26743932

  9. Low-Dose Oxygen Enhances Macrophage-Derived Bacterial Clearance following Cigarette Smoke Exposure

    PubMed Central

    Bain, William G.; Tripathi, Ashutosh; Mandke, Pooja; Gans, Jonathan H.; D'Alessio, Franco R.; Sidhaye, Venkataramana K.; Aggarwal, Neil R.

    2016-01-01

    Background. Chronic obstructive pulmonary disease (COPD) is a common, smoking-related lung disease. Patients with COPD frequently suffer disease exacerbations induced by bacterial respiratory infections, suggestive of impaired innate immunity. Low-dose oxygen is a mainstay of therapy during COPD exacerbations; yet we understand little about whether oxygen can modulate the effects of cigarette smoke on lung immunity. Methods. Wild-type mice were exposed to cigarette smoke for 5 weeks, followed by intratracheal instillation of Pseudomonas aeruginosa (PAO1) and 21% or 35–40% oxygen. After two days, lungs were harvested for PAO1 CFUs, and bronchoalveolar fluid was sampled for inflammatory markers. In culture, macrophages were exposed to cigarette smoke and oxygen (40%) for 24 hours and then incubated with PAO1, followed by quantification of bacterial phagocytosis and inflammatory markers. Results. Mice exposed to 35–40% oxygen after cigarette smoke and PAO1 had improved survival and reduced lung CFUs and inflammation. Macrophages from these mice expressed less TNF-α and more scavenger receptors. In culture, macrophages exposed to cigarette smoke and oxygen also demonstrated decreased TNF-α secretion and enhanced phagocytosis of PAO1 bacteria. Conclusions. Our findings demonstrate a novel, protective role for low-dose oxygen following cigarette smoke and bacteria exposure that may be mediated by enhanced macrophage phagocytosis. PMID:27403445

  10. Increased surfactant protein D fails to improve bacterial clearance and inflammation in serpinB1-/- mice.

    PubMed

    Stolley, J Michael; Gong, Dapeng; Farley, Kalamo; Zhao, Picheng; Cooley, Jessica; Crouch, Erika C; Benarafa, Charaf; Remold-O'Donnell, Eileen

    2012-12-01

    Previously, we described the protective role of the neutrophil serine protease inhibitor serpinB1 in preventing early mortality of Pseudomonas aeruginosa lung infection by fostering bacterial clearance and limiting inflammatory cytokines and proteolytic damage. Surfactant protein D (SP-D), which maintains the antiinflammatory pulmonary environment and mediates bacterial removal, was degraded in infected serpinB1-deficient mice. Based on the hypothesis that increased SP-D would rescue or mitigate the pathological effects of serpinB1 deletion, we generated two serpinB1(-/-) lines overexpressing lung-specific rat SP-D and inoculated the mice with P. aeruginosa. Contrary to predictions, bacterial counts in the lungs of SP-D(low)serpinB1(-/-) and SP-D(high) serpinB1(-/-) mice were 4 logs higher than wild-type and not different from serpinB1(-/-) mice. SP-D overexpression also failed to mitigate inflammation (TNF-α), lung injury (free protein, albumin), or excess neutrophil death (free myeloperoxidase, elastase). These pathological markers were higher for infected SP-D(high)serpinB1(-/-) mice than for serpinB1(-/-) mice, although the differences were not significant after controlling for multiple comparisons. The failure of transgenic SP-D to rescue antibacterial defense of serpinB1-deficient mice occurred despite 5-fold or 20-fold increased expression levels, largely normal structure, and dose-dependent bacteria-aggregating activity. SP-D of infected wild-type mice was intact in 43-kD monomers by reducing SDS-PAGE. By contrast, proteolytic fragments of 35, 17, and 8 kD were found in infected SP-D(low)serpinB1(-/-), SP-D(high) serpinB1(-/-) mice, and serpinB1(-/-) mice. Thus, although therapies to increase lung concentration of SP-D may have beneficial applications, the findings suggest that therapy with SP-D may not be beneficial for lung inflammation or infection if the underlying clinical condition includes excess proteolysis. PMID:23024061

  11. Cigarette Smoke Exposure Impairs Pulmonary Bacterial Clearance and Alveolar Macrophage Complement-Mediated Phagocytosis of Streptococcus pneumoniae▿

    PubMed Central

    Phipps, John C.; Aronoff, David M.; Curtis, Jeffrey L.; Goel, Deepti; O'Brien, Edmund; Mancuso, Peter

    2010-01-01

    Cigarette smoke exposure increases the risk of pulmonary and invasive infections caused by Streptococcus pneumoniae, the most commonly isolated organism from patients with community-acquired pneumonia. Despite this association, the mechanisms by which cigarette smoke exposure diminishes host defense against S. pneumoniae infections are poorly understood. In this study, we compared the responses of BALB/c mice following an intratracheal challenge with S. pneumoniae after 5 weeks of exposure to room air or cigarette smoke in a whole-body exposure chamber in vivo and the effects of cigarette smoke on alveolar macrophage phagocytosis of S. pneumoniae in vitro. Bacterial burdens in cigarette smoke-exposed mice were increased at 24 and 48 h postinfection, and this was accompanied by a more pronounced clinical appearance of illness, hypothermia, and increased lung homogenate cytokines interleukin-1β (IL-1β), IL-6, IL-10, and tumor necrosis factor alpha (TNF-α). We also found greater numbers of neutrophils in bronchoalveolar lavage fluid recovered from cigarette smoke-exposed mice following a challenge with heat-killed S. pneumoniae. Interestingly, overnight culture of alveolar macrophages with 1% cigarette smoke extract, a level that did not affect alveolar macrophage viability, reduced complement-mediated phagocytosis of S. pneumoniae, while the ingestion of unopsonized bacteria or IgG-coated microspheres was not affected. This murine model provides robust additional support to the hypothesis that cigarette smoke exposure increases the risk of pneumococcal pneumonia and defines a novel cellular mechanism to help explain this immunosuppressive effect. PMID:20008540

  12. Mucosal immunisation with novel Streptococcus pneumoniae protein antigens enhances bacterial clearance in an acute mouse lung infection model.

    PubMed

    Jomaa, Maha; Kyd, Jennelle M; Cripps, Allan W

    2005-04-01

    Streptococcus pneumoniae contains many proteins that have not been evaluated as potential protective vaccine antigens. In this study we isolated proteins from a serotype 3 strain of S. pneumoniae for use in mouse immunisation studies. Separation of the protein mix was achieved by SDS-PAGE electrophoresis followed by electro-elution to isolate individual proteins. This procedure successfully separated 21 fractions from which six proteins were selected based on purity and quantity and were initially denoted by their molecular masses: 14-, 34-, 38-, 48-, 57- and 75-kDa. The immunogenicity of these proteins was investigated in a mucosal immunisation model in mice involving a primary inoculation to the intestinal Peyer's patches followed by an intra-tracheal boost two weeks later. The immune response was assessed by enhancement of pulmonary clearance of infection, recruitment of phagocytes to the lungs and induction of an antibody response. Two of the proteins, the 14-kDa identified as a L7/L12 ribosomal protein, and the 34-kDa identified as glyceraldehyde-3-phosphate dehydrogenase resulted in up to 99% and 94%, respectively, enhanced clearance of infection within 5 h following pulmonary challenge with S. pneumoniae. This study has shown that novel pneumococcal proteins have the potential to be vaccine candidates to enhance clearance of an acute mucosal S. pneumoniae infection. PMID:15780579

  13. Disorders of diminished motivation.

    PubMed

    Marin, Robert S; Wilkosz, Patricia A

    2005-01-01

    Disorders of diminished motivation occur frequently in individuals with traumatic brain injury. Motivation is an ever-present, essential determinant of behavior and adaptation. The major syndromes of diminished motivation are apathy, abulia, and akinetic mutism. Depending on their etiology, disorders of diminished motivation may be a primary clinical disturbance, a symptom of another disorder, or a coexisting second disorder. This article presents a biopsychosocial approach to the assessment and management of motivational impairments in patients with traumatic brain injury. The recognition and differential diagnosis of disorders of diminished motivation, as well as the mechanism and clinical pathogenesis, are discussed. PMID:16030444

  14. In vivo study on the immunomodulating effects of OM-85 BV on survival, inflammatory cell recruitment and bacterial clearance in Klebsiella pneumonia.

    PubMed

    Broug-Holub, E; Kraal, G

    1997-01-01

    Oral administration of the bacterial extract OM-85 BV has been shown to prime alveolar macrophages (AM) in such a way that they secrete significantly more nitric oxide, tumor necrosis factor-alpha and interleukin-1beta upon in vitro stimulation with lipopolysaccharide (LPS). As increased cytokine secretion by AM may account for the therapeutic effect of OM-85 BV in respiratory tract infections, we studied the effect of orally administered OM-85 BV on the outcome of Klebsiella pneumoniae-induced pneumonia. Mice received a daily oral dose of OM-85 BV (350 mg/kg body weight) for 5 days and were intratracheally infected with 333, 1000 or 3333 CFU K. pneumoniae on day 8. It was shown that OM-85 BV pretreatment of mice has no effect on bacterial clearance, neutrophil recruitment and survival in this acute respiratory tract infection. Also, OM-85 BV treatment had no protective effect in a recurrent infection with K. pneumoniae. It is concluded that AM activation by oral treatment with OM-85 BV is not sufficient to play a protective role in respiratory tract infection with K. pneumoniae. PMID:9637354

  15. The Diminishing Apple.

    ERIC Educational Resources Information Center

    Kelly, Catherine

    2002-01-01

    Introduces the Apple Ocean activity which teaches about the diminishing natural resources of the earth including drinkable water, habitable land, and productive areas while working with fractions, ratios, and proportions. (YDS)

  16. Nucleation of platelets with bloodborne pathogens on Kupffer cell precedes other innate immunity and contributes to bacterial clearance

    PubMed Central

    Wong, Connie H. Y.; Jenne, Craig N.; Petri, Björn; Chrobok, Navina L.; Kubes, Paul

    2016-01-01

    Using intravital imaging of the liver, we unveil a collaborative role for platelets with Kupffer cells (KCs) in eradicating bloodborne bacterial infections. Under basal conditions, platelets via glycoprotein Ib (GPIb) formed transient “touch-and-go” interactions with von Willebrand factor (vWF) constitutively expressed on KCs. Bacteria, such as Bacillus cereus and Methicillin-resistant Staphylococcus aureus (MRSA), were rapidly caught by KCs and triggered platelets to switch from “touch-and-go” to sustained GPIIb-mediated adhesion on the KC surface to encase the bacterium. Infected GpIbα−/− mice demonstrated increased endothelial and KC damage, leading to increased fluid leakage, significant polycythemia and rapid mortality. This study identifies a novel surveillance mechanism of intravascular macrophage by platelets that rapidly converts to a critical host response against bloodborne bacteria. PMID:23770641

  17. Vaccination with Brucella abortus recombinant in vivo-induced antigens reduces bacterial load and promotes clearance in a mouse model for infection.

    PubMed

    Lowry, Jake E; Isaak, Dale D; Leonhardt, Jack A; Vernati, Giulia; Pate, Jessie C; Andrews, Gerard P

    2011-01-01

    Current vaccines used for the prevention of brucellosis are ineffective in inducing protective immunity in animals that are chronically infected with Brucella abortus, such as elk. Using a gene discovery approach, in vivo-induced antigen technology (IVIAT) on B. abortus, we previously identified ten loci that encode products up-regulated during infection in elk and consequently may play a role in virulence. In our present study, five of the loci (D15, 0187, VirJ, Mdh, AfuA) were selected for further characterization and compared with three additional antigens with virulence potential (Hia, PrpA, MltA). All eight genes were PCR-amplified from B. abortus and cloned into E. coli. The recombinant products were then expressed, purified, adjuvanted, and delivered subcutaneously to BALB/c mice. After primary immunization and two boosts, mice were challenged i.p. with 5 x 10⁴ CFU of B. abortus strain 19. Spleens from challenged animals were harvested and bacterial loads determined by colony count at various time points. While vaccination with four of the eight individual proteins appeared to have some effect on clearance kinetics, mice vaccinated with recombinant Mdh displayed the most significant reduction in bacterial colonization. Furthermore, mice immunized with Mdh maintained higher levels of IFN-γ in spleens compared to other treatment groups. Collectively, our in vivo data gathered from the S19 murine colonization model suggest that vaccination with at least three of the IVIAT antigens conferred an enhanced ability of the host to respond to infection, reinforcing the utility of this methodology for the identification of potential vaccine candidates against brucellosis. Mechanisms for immunity to one protein, Mdh, require further in vitro exploration and evaluation against wild-type B. abortus challenge in mice, as well as other hosts. Additional studies are being undertaken to clarify the role of Mdh and other IVI antigens in B. abortus virulence and induction of

  18. Reduced Bacterial Colony Count of Anaerobic Bacteria Is Associated with a Worsening in Lung Clearance Index and Inflammation in Cystic Fibrosis

    PubMed Central

    Bradley, Judy M.; Johnston, Elinor; McGrath, Stephanie; McIlreavey, Leanne; Rowan, Stephen; Reid, Alastair; Bradbury, Ian; Einarsson, Gisli

    2015-01-01

    Anaerobic bacteria have been identified in abundance in the airways of cystic fibrosis (CF) subjects. The impact their presence and abundance has on lung function and inflammation is unclear. The aim of this study was to investigate the relationship between the colony count of aerobic and anaerobic bacteria, lung clearance index (LCI), spirometry and C-Reactive Protein (CRP) in patients with CF. Sputum and blood were collected from CF patients at a single cross-sectional visit when clinically stable. Community composition and bacterial colony counts were analysed using extended aerobic and anaerobic culture. Patients completed spirometry and a multiple breath washout (MBW) test to obtain LCI. An inverse correlation between colony count of aerobic bacteria (n = 41, r = -0.35; p = 0.02), anaerobic bacteria (n = 41, r = -0.44, p = 0.004) and LCI was observed. There was an inverse correlation between colony count of anaerobic bacteria and CRP (n = 25, r = -0.44, p = 0.03) only. The results of this study demonstrate that a lower colony count of aerobic and anaerobic bacteria correlated with a worse LCI. A lower colony count of anaerobic bacteria also correlated with higher CRP levels. These results indicate that lower abundance of aerobic and anaerobic bacteria may reflect microbiota disruption and disease progression in the CF lung. PMID:25992575

  19. Improvement of bacterial clearance and relief of clinical signs of Salmonella enterica serovar Typhimurium infection in pigs through upregulation of Th 1-specific responses by administration of a combination of two silicate minerals, biotite and bentonite

    PubMed Central

    LEE, Jin-A; JUNG, Bock-Gie; KIM, Tae-Hoon; KIM, Yun-Mi; KOH, Hong-Bum; LEE, Bong-Joo

    2015-01-01

    Biotite and bentonite are phyllosilicate minerals that were originally used in industrial applications. Several beneficial activities of them have recently been reported, especially regulation of the immune system and antimicrobial effects. Therefore, we investigated the immune-enhancing and bacterial clearance effects of a biotite and bentonite mixture (BBM) on experimental infection of Salmonella enterica serovar Typhimurium (S. Typhimurium) to determine whether the BBM could be used as an alternative antibiotic. We administered 1% or 2% BBM as a feed supplement. We then evaluated the bacterial clearance effects of the BBM against S. Typhimurium. We also evaluated the immune-enhancing effect of the BBM through several immunological experiments that included examination of the lysozyme activity, CD4+/CD8+ T lymphocyte ratio and the T-helper type 1 (Th 1) cytokine profile. The clinical signs of S. Typhimurium and the number of viable bacteria in feces and tissues were significantly decreased in both BBM groups, especially in the 2% BBM group. The BBM also markedly enhanced the lysozyme activity, CD4+/CD8+ T lymphocyte ratio and expression levels of IFN-γ and IL-12 in S. Typhimurium-challenged pigs. Therefore, the BBM could be a good candidate as an alternative antibiotic that improves Th 1-specific immune responses and the bacterial clearance effect. PMID:25947887

  20. A vaccine based on a mutant transferrin binding protein B of Haemophilus parasuis induces a strong T-helper 2 response and bacterial clearance after experimental infection.

    PubMed

    Martínez-Martínez, Sonia; Frandoloso, Rafael; Rodríguez-Ferri, Elías-Fernando; García-Iglesias, María-José; Pérez-Martínez, Claudia; Álvarez-Estrada, Álvaro; Gutiérrez-Martín, César-Bernardo

    2016-10-15

    This study aimed to characterize the type of immune response induced by an experimental vaccine based on a mutant Haemophilus parasuis transferrin binding protein (Tbp) B (Y167A) defective in its ability to bind porcine transferrin. Clinical and pathological signs, bacterial clearance, antibody response and the cytokine profile in alveolar macrophages and spleen after the vaccination and challenge of twenty-two colostrum-deprived pigs with 10(8) CFU of H. parasuis were analysed. Pigs vaccinated with Y167A were compared to those vaccinated with native TbpB (nTbpB), those treated with a commercial bacterin (CB) against Glässer's disease, those unvaccinated challenged (CH) and those unvaccinated unchallenged (UNCH) pigs. The rectal temperatures of Y167A pigs resembled those of UNCH pigs and were significantly lower than those of the nTbpB, CB and CH animals. A major reduction in pathological changes of the challenged pigs was observed in the Y167A group. H. parasuis was cleared from 88.9% of the samples from Y167A pigs versus 60.0% and 55.6% from those of the CB and nTbpB groups, respectively. The antibody response elicited by Y167A by ELISA was notably higher than that observed for nTbpB and CB pigs and was capable of preventing the expression and secretion of IL-8. The expression of IL-4 and IL-5, which were associated with the specific antibody levels, suggests that the main mechanism of protection conferred by Y167A vaccine is based on a strong T-helper 2 response. PMID:27590421

  1. MyD88 Deficiency Markedly Worsens Tissue Inflammation and Bacterial Clearance in Mice Infected with Treponema pallidum, the Agent of Syphilis

    PubMed Central

    Silver, Adam C.; Dunne, Dana W.; Zeiss, Caroline J.; Bockenstedt, Linda K.; Radolf, Justin D.; Salazar, Juan C.; Fikrig, Erol

    2013-01-01

    Research on syphilis, a sexually transmitted infection caused by the non-cultivatable spirochete Treponema pallidum, has been hampered by the lack of an inbred animal model. We hypothesized that Toll-like receptor (TLR)-dependent responses are essential for clearance of T. pallidum and, consequently, compared infection in wild-type (WT) mice and animals lacking MyD88, the adaptor molecule required for signaling by most TLRs. MyD88-deficient mice had significantly higher pathogen burdens and more extensive inflammation than control animals. Whereas tissue infiltrates in WT mice consisted of mixed mononuclear and plasma cells, infiltrates in MyD88-deficient animals were predominantly neutrophilic. Although both WT and MyD88-deficient mice produced antibodies that promoted uptake of treponemes by WT macrophages, MyD88-deficient macrophages were deficient in opsonophagocytosis of treponemes. Our results demonstrate that TLR-mediated responses are major contributors to the resistance of mice to syphilitic disease and that MyD88 signaling and FcR-mediated opsonophagocytosis are linked to the macrophage-mediated clearance of treponemes. PMID:23940747

  2. Sociable Sequences and Diminishing Functions.

    ERIC Educational Resources Information Center

    Sprows, David

    1989-01-01

    A FORTRAN program is provided for use with computer projects for a course in number theory. Uses diminishing functions and the speed of the computer to quickly determine possible solutions to problems. (MVL)

  3. Pre-adapting parasitic phages to a pathogen leads to increased pathogen clearance and lowered resistance evolution with Pseudomonas aeruginosa cystic fibrosis bacterial isolates.

    PubMed

    Friman, V-P; Soanes-Brown, D; Sierocinski, P; Molin, S; Johansen, H K; Merabishvili, M; Pirnay, J-P; De Vos, D; Buckling, A

    2016-01-01

    Recent years have seen renewed interest in phage therapy--the use of viruses to specifically kill disease-causing bacteria--because of the alarming rise in antibiotic resistance. However, a major limitation of phage therapy is the ease at with bacteria can evolve resistance to phages. Here, we determined whether in vitro experimental coevolution can increase the efficiency of phage therapy by limiting the resistance evolution of intermittent and chronic cystic fibrosis Pseudomonas aeruginosa lung isolates to four different phages. We first pre-adapted all phage strains against all bacterial strains and then compared the efficacy of pre-adapted and nonadapted phages against ancestral bacterial strains. We found that evolved phages were more efficient in reducing bacterial densities than ancestral phages. This was primarily because only 50% of bacterial strains were able to evolve resistance to evolved phages, whereas all bacteria were able to evolve some level of resistance to ancestral phages. Although the rate of resistance evolution did not differ between intermittent and chronic isolates, it incurred a relatively higher growth cost for chronic isolates when measured in the absence of phages. This is likely to explain why evolved phages were more effective in reducing the densities of chronic isolates. Our data show that pathogen genotypes respond differently to phage pre-adaptation, and as a result, phage therapies might need to be individually adjusted for different patients. PMID:26476097

  4. Inhibition of High-Mobility Group Box 1 Protein (HMGB1) Enhances Bacterial Clearance and Protects against Pseudomonas Aeruginosa Pneumonia in Cystic Fibrosis

    PubMed Central

    Entezari, Maria; Weiss, Daniel J; Sitapara, Ravikumar; Whittaker, Laurie; Wargo, Matthew J; Li, JianHua; Wang, Haichao; Yang, Huan; Sharma, Lokesh; Phan, Binh D; Javdan, Mohammad; Chavan, Sangeeta S; Miller, Edmund J; Tracey, Kevin J; Mantell, Lin L

    2012-01-01

    Pulmonary infection with Pseudomonas aeruginosa and neutrophilic lung inflammation significantly contribute to morbidity and mortality in cystic fibrosis (CF). High-mobility group box 1 protein (HMGB1), a ubiquitous DNA binding protein that promotes inflammatory tissue injury, is significantly elevated in CF sputum. However, its mechanistic and potential therapeutic implications in CF were previously unknown. We found that HMGB1 levels were significantly elevated in bronchoalveolar lavage fluids (BALs) of CF patients and cystic fibrosis transmembrane conductance regulator (CFTR )−/− mice. Neutralizing anti-HMGB1 monoclonal antibody (mAb) conferred significant protection against P. aeruginosa–induced neutrophil recruitment, lung injury and bacterial infection in both CFTR−/− and wild-type mice. Alveolar macrophages isolated from mice treated with anti-HMGB1 mAb had improved phagocytic activity, which was suppressed by direct exposure to HMGB1. In addition, BAL from CF patients significantly impaired macrophage phagocytotic function, and this impairment was attenuated by HMGB1-neutralizing antibodies. The HMGB1-mediated suppression of bacterial phagocytosis was attenuated in macrophages lacking toll-like receptor (TLR)-4, suggesting a critical role for TLR4 in signaling HMGB1-mediated macrophage dysfunction. These studies demonstrate that the elevated levels of HMGB1 in CF airways are critical for neutrophil recruitment and persistent presence of P. aeruginosa in the lung. Thus, HMGB1 may provide a therapeutic target for reducing bacterial infection and lung inflammation in CF. PMID:22314397

  5. Diminishing Returns in Humanities Research

    ERIC Educational Resources Information Center

    Bauerlein, Mark

    2009-01-01

    The author discusses the shift from criticism-as-explanation to criticism-as-performance that has taken place in literary criticism over the past five decades, and the resultant surge in published offerings to what has become a diminishing audience. The question of supersaturation applies to the institutions that demand and reward humanities…

  6. Mucus clearance, MyD88-dependent and MyD88-independent immunity modulate lung susceptibility to spontaneous bacterial infection and inflammation

    PubMed Central

    Livraghi-Butrico, Alessandra; Kelly, E. Jane; Klem, Erich R.; Dang, Hong; Wolfgang, Matthew C.; Boucher, Richard C.; Randell, Scott H.; O’Neal, Wanda K.

    2012-01-01

    It has been postulated that mucus stasis is central to the pathogenesis of obstructive lung diseases. In Scnn1b-transgenic (Scnn1b-Tg+) mice, airway-targeted overexpression of the epithelial Na+ channel β subunit causes airway surface dehydration, which results in mucus stasis and inflammation. Bronchoalveolar lavage from neonatal Scnn1b-Tg+ mice, but not wild-type littermates, contained increased mucus, bacteria, and neutrophils, which declined with age. Scnn1b-Tg+ mice lung bacterial flora included environmental and oropharyngeal species, suggesting inhalation and/or aspiration as routes of entry. Genetic deletion of the Toll/Interleukin-1 receptor adapter molecule MyD88 in Scnn1b-Tg+ mice did not modify airway mucus obstruction, but caused defective neutrophil recruitment and increased bacterial infection, which persisted into adulthood. Scnn1b-Tg+ mice derived into germ-free conditions exhibited mucus obstruction similar to conventional Scnn1b-Tg+ mice and sterile inflammation. Collectively, these data suggest that dehydration-induced mucus stasis promotes infection, compounds defects in other immune mechanisms, and alone is sufficient to trigger airway inflammation. PMID:22419116

  7. Arginine-supplemented diets improve survival in gut-derived sepsis and peritonitis by modulating bacterial clearance. The role of nitric oxide.

    PubMed Central

    Gianotti, L; Alexander, J W; Pyles, T; Fukushima, R

    1993-01-01

    OBJECTIVE: The effect of arginine on survival rates and host defense mechanisms was studied using two clinically relevant models of infection that included transfusion-induced immunosuppression. SUMMARY BACKGROUND DATA: Dietary arginine will improve resistance to infection but its role in transfusion-induced immunosuppression and bacterial translocation (gut-derived sepsis) has not been defined. METHODS: Balb/c mice were fed for 10 days with either a defined AIN-76A diet, an AIN-76A diet supplemented with 2% arginine, an AIN-76A diet supplemented with 4% glycine, or standard laboratory chow. In most experiments, the mice were then transfused with allogeneic blood and allowed to feed for an additional 5 days before undergoing either cecal ligation and puncture (CLP) or gavage with 10(10) Escherichia coli and a 20% burn injury. Additional animals fed with the arginine supplemented diet were treated with the nitric oxide inhibitor N omega-Nitro-L-arginine (NNA) before gavage and burn. The effect of these diets and NNA on the degree of translocation of 14C-radiolabeled E. coli from the intestine and the ability of the host to kill translocated organisms was also investigated. Mice were fed and received transfusion, gavage, and burn as above. Mesenteric lymph nodes (MLN), liver and spleen were harvested 4 hours postburn. RESULTS: Survival after CLP was 56% in the arginine-supplemented group versus 28% in the AIN-76A group and 20% in the chow group (p < 0.02). After gavage and burn, survival was 100% in the arginine-supplemented group versus 50% in both the glycine-supplemented and chow groups and 35% in the AIN-76A group (p < 0.01). In animals receiving the arginine-supplemented diet, treatment with NNA decreased survival from 95% to 30.5% (p < 0.0001). Greater translocation, as measured by radionuclide counts, was observed to the MLN of the AIN-76A group. However, there was no difference in translocation to the liver and spleen related to dietary group. Quantitative

  8. Acute psychological stress reduces plasma triglyceride clearance.

    PubMed

    Stoney, Catherine M; West, Sheila G; Hughes, Joel W; Lentino, Lisa M; Finney, Montenique L; Falko, James; Bausserman, Linda

    2002-01-01

    Acute stress elevates blood lipids, with the largest increases among men and postmenopausal women. The mechanisms for the effect are unknown, but may be due to altered lipid metabolism. This study investigated if acute stress induces transient reductions in triglyceride clearance in middle-aged men and women, and determined if gender and menopause affect triglyceride metabolism. Of the 35 women, half were premenopausal, and half were naturally postmenopausal; men (n = 35) were age matched. Clearance of an intravenously administered fat emulsion was assessed twice: once during a nonstress session, and again during a stress-testing session. During the stress session, a battery of behavioral stressors (serial subtraction, speech, mirror tracing, and Stroop) were performed for 40 min. The clearance rate of exogenous fat was significantly diminished during the stress, relative to the nonstress session. Women had more efficient clearance, relative to men, but there were no effects of menopausal status. The diminished ability to clear an intravenous fat emulsion during stress suggests one mechanism for stress-induced elevations in lipids. PMID:12206298

  9. Gait Variability in Chronic Back Pain Sufferers With Experimentally Diminished Visual Feedback: A Pilot Study.

    PubMed

    Hamacher, Dennis; Hamacher, Daniel; Krowicki, Martin; Schega, Lutz

    2016-01-01

    Increased gait variability is common in chronic low back pain patients, which is a sign of their diminished proprioceptive feedback. When proprioceptive information is reduced, vision partly takes over the role of proprioception. Therefore, a loss of visual feedback would have a more negative effect in individuals with diminished proprioception. To test this hypothesis, 14 healthy individuals and 14 chronic low back pain patients walked with and without impairment goggles manipulating visual feedback. The variability of stride time, stride length, and minimum foot clearance was evaluated. The authors observed an interaction effect regarding minimum foot clearance variability indicating that pain patients showed higher gait variability with manipulated visual feedback. Reduced vision may cause exceeded tripping risk in individuals with diminished proprioception. PMID:26339981

  10. Diminishing Marginal Utility in Economics Textbooks

    ERIC Educational Resources Information Center

    Dittmer, Timothy

    2005-01-01

    Many introductory microeconomics textbook authors derive the law of demand from the assumption of diminishing marginal utility. Authors of intermediate and graduate textbooks derive demand from diminishing marginal rate of substitution and ordinal preferences. These approaches are not interchangeable; diminishing marginal utility for all goods is…

  11. Advanced Thermal HPT Clearance Control

    NASA Technical Reports Server (NTRS)

    WojciechVoytek, Sak

    2006-01-01

    OBJECTIVE: Develop a fast acting HPT Active Clearance Control System to improve engine efficiency and reduce emissions CHALLENGE: Reduction of HPT blade clearance throughout engine operation System complexity, reliability and cost must remain comparable or surpass today s engines Reduced clearance may increase possibility of rubs

  12. Does Public Employee Unionism Diminish Democracy?

    ERIC Educational Resources Information Center

    Cohen, Sanford

    1979-01-01

    The author considers charges that public sector unionism diminishes democracy by requiring a sharing of public authority with private bodies that too often exerts disproportionate influence on government decisions. He questions these charges in view of declining public unionism and unrealistic assumptions about the nature of local government…

  13. Renal Clearance of Nanoparticles

    PubMed Central

    Choi, Hak Soo; Liu, Wenhao; Misra, Preeti; Tanaka, Eiichi; Zimmer, John P.; Ipe, Binil Itty; Bawendi, Moungi G.; Frangioni, John V.

    2008-01-01

    SUMMARY The field of nanotechnology holds great promise for the diagnosis and treatment of human disease. However, the size and charge of most nanoparticles preclude their efficient clearance from the body as intact nanoparticles. Without such clearance or their biodegradation into biologically benign components, toxicity is potentially amplified and radiological imaging is hindered. Using quantum dots (QDs) as a model system, we have precisely defined the requirements for renal filtration and urinary excretion of inorganic, metal-containing nanoparticles. Zwitterionic or neutral organic coatings prevented adsorption of serum proteins, which otherwise increased hydrodynamic diameter (HD) by over 15 nm and prevented renal excretion. A final HD smaller than 5.5 nm resulted in rapid and efficient urinary excretion, and elimination of QDs from the body. This study provides a foundation for the design and development of biologically targeted nanoparticles for biomedical applications. PMID:17891134

  14. Diminished Schwann cell repair responses underlie age-associated impaired axonal regeneration

    PubMed Central

    Painter, Michio W.; Brosius Lutz, Amanda; Cheng, Yung-Chih; Latremoliere, Alban; Duong, Kelly; Miller, Christine M.; Posada, Sean; Cobos, Enrique J.; Zhang, Alice X.; Wagers, Amy J.; Havton, Leif A.; Barres, Ben; Omura, Takao

    2014-01-01

    SUMMARY The regenerative capacity of the peripheral nervous system declines with age. Why this occurs, however, is unknown. We demonstrate that 24-month old mice exhibit an impairment of functional recovery after nerve injury compared to 2-month old animals. We find no difference in the intrinsic growth capacity between aged and young sensory neurons in vitro nor in their ability to activate growth-associated transcriptional programs after injury. Instead, using age-mismatched nerve transplants in vivo, we show that the extent of functional recovery depends on the age of the nerve graft, and not the age of the host. Molecular interrogation of the sciatic nerve reveals that aged Schwann cells (SCs) fail to rapidly activate a transcriptional repair program after injury. Functionally, aged SCs exhibit impaired de-differentiation, myelin clearance and macrophage recruitment. These results suggest that the age-associated decline in axonal regeneration results from diminished Schwann cell plasticity, leading to slower myelin clearance. PMID:25033179

  15. Diminished Schwann cell repair responses underlie age-associated impaired axonal regeneration.

    PubMed

    Painter, Michio W; Brosius Lutz, Amanda; Cheng, Yung-Chih; Latremoliere, Alban; Duong, Kelly; Miller, Christine M; Posada, Sean; Cobos, Enrique J; Zhang, Alice X; Wagers, Amy J; Havton, Leif A; Barres, Ben; Omura, Takao; Woolf, Clifford J

    2014-07-16

    The regenerative capacity of the peripheral nervous system declines with age. Why this occurs, however, is unknown. We demonstrate that 24-month-old mice exhibit an impairment of functional recovery after nerve injury compared to 2-month-old animals. We find no difference in the intrinsic growth capacity between aged and young sensory neurons in vitro or in their ability to activate growth-associated transcriptional programs after injury. Instead, using age-mismatched nerve transplants in vivo, we show that the extent of functional recovery depends on the age of the nerve graft, and not the age of the host. Molecular interrogation of the sciatic nerve reveals that aged Schwann cells (SCs) fail to rapidly activate a transcriptional repair program after injury. Functionally, aged SCs exhibit impaired dedifferentiation, myelin clearance, and macrophage recruitment. These results suggest that the age-associated decline in axonal regeneration results from diminished Schwann cell plasticity, leading to slower myelin clearance. PMID:25033179

  16. Site clearance working group

    SciTech Connect

    1997-03-01

    The Gulf of Mexico and Louisiana continue to be areas with a high level of facility removal, and the pace of removal is projected to increase. Regulations were promulgated for the Gulf of Mexico and Louisiana requiring that abandoned sites be cleared of debris that could interfere with fishing and shrimping activities. The site clearance regulations also required verification that the sites were clear. Additionally, government programs were established to compensate fishermen for losses associated with snagging their equipment on oil and gas related objects that remained on the water bottoms in areas other than active producing sites and sites that had been verified as clear of obstructions and snags. The oil and gas industry funds the compensation programs. This paper reviews the regulations and evolving operating practices in the Gulf of Mexico and Louisiana where site clearance and fisherman`s gear compensation regulations have been in place for a number of years. Although regulations and guidelines may be in place elsewhere in the world, this paper focuses on the Gulf of Mexico and Louisiana. Workshop participants are encouraged to bring up international issues during the course of the workshop. Additionally, this paper raises questions and focuses on issues that are of concern to the various Gulf of Mexico and Louisiana water surface and water bottom stakeholders. This paper does not have answers to the questions or issues. During the workshop participants will debate the questions and issues in an attempt to develop consensus opinions and/or make suggestions that can be provided to the appropriate organizations, both private and government, for possible future research or policy adjustments. Site clearance and facility removal are different activities. Facility removal deals with removal of the structures used to produce oil and gas including platforms, wells, casing, piles, pipelines, well protection structures, etc.

  17. Turbomachinery Clearance Control

    NASA Technical Reports Server (NTRS)

    Chupp, Raymond E.; Hendricks, Robert C.; Lattime, Scott B.; Steinetz, Bruce M.; Aksit, Mahmut F.

    2007-01-01

    Controlling interface clearances is the most cost effective method of enhancing turbomachinery performance. Seals control turbomachinery leakages, coolant flows and contribute to overall system rotordynamic stability. In many instances, sealing interfaces and coatings are sacrificial, like lubricants, giving up their integrity for the benefit of the component. They are subjected to abrasion, erosion, oxidation, incursive rubs, foreign object damage (FOD) and deposits as well as extremes in thermal, mechanical, aerodynamic and impact loadings. Tribological pairing of materials control how well and how long these interfaces will be effective in controlling flow. A variety of seal types and materials are required to satisfy turbomachinery sealing demands. These seals must be properly designed to maintain the interface clearances. In some cases, this will mean machining adjacent surfaces, yet in many other applications, coatings are employed for optimum performance. Many seals are coating composites fabricated on superstructures or substrates that are coated with sacrificial materials which can be refurbished either in situ or by removal, stripping, recoating and replacing until substrate life is exceeded. For blade and knife tip sealing an important class of materials known as abradables permit blade or knife rubbing without significant damage or wear to the rotating element while maintaining an effective sealing interface. Most such tip interfaces are passive, yet some, as for the high-pressure turbine (HPT) case or shroud, are actively controlled. This work presents an overview of turbomachinery sealing. Areas covered include: characteristics of gas and steam turbine sealing applications and environments, benefits of sealing, types of standard static and dynamics seals, advanced seal designs, as well as life and limitations issues.

  18. Indole and 7-hydroxyindole diminish Pseudomonas aeruginosa virulence.

    PubMed

    Lee, Jintae; Attila, Can; Cirillo, Suat L G; Cirillo, Jeffrey D; Wood, Thomas K

    2009-01-01

    Indole is an extracellular biofilm signal for Escherichia coli, and many bacterial oxygenases readily convert indole to various oxidized compounds including 7-hydroxyindole (7HI). Here we investigate the impact of indole and 7HI on Pseudomonas aeruginosa PAO1 virulence and quorum sensing (QS)-regulated phenotypes; this strain does not synthesize these compounds but degrades them rapidly. Indole and 7HI both altered extensively gene expression in a manner opposite that of acylhomoserine lactones; the most repressed genes encode the mexGHI-opmD multidrug efflux pump and genes involved in the synthesis of QS-regulated virulence factors including pyocyanin (phz operon), 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS) signal (pqs operon), pyochelin (pch operon) and pyoverdine (pvd operon). Corroborating these microarray results, indole and 7HI decreased production of pyocyanin, rhamnolipid, PQS and pyoverdine and enhanced antibiotic resistance. In addition, indole affected the utilization of carbon, nitrogen and phosphorus, and 7HI abolished swarming motility. Furthermore, 7HI reduced pulmonary colonization of P. aeruginosa in guinea pigs and increased clearance in lungs. Hence, indole-related compounds have potential as a novel antivirulence approach for the recalcitrant pathogen P. aeruginosa. PMID:21261883

  19. Monocyte Trafficking to Hepatic Sites of Bacterial Infection Is Chemokine Independent and Directed by Focal Intercellular Adhesion Molecule-1 Expression

    PubMed Central

    Shi, Chao; Velázquez, Peter; Hohl, Tobias M.; Leiner, Ingrid; Dustin, Michael L.; Pamer, Eric G.

    2010-01-01

    Recruitment of CCR2+Ly6Chigh monocytes to sites of infection is essential for efficient clearance of microbial pathogens. Although CCR2-mediated signals promote monocyte emigration from bone marrow, the contribution of CCR2 to later stages of monocyte recruitment remains unresolved. In this article, we show that CCR2 deficiency markedly worsens hepatic Listeria monocytogenes infection because Ly6Chigh monocytes are retained in the bone marrow. Intravenously transferred, CCR2-deficient Ly6Chigh monocytes traffic normally to hepatic foci of infection and contribute to bacterial clearance. Pertussis toxin treatment of adoptively transferred monocytes does not impair their intrahepatic trafficking, suggesting that chemokine signaling, once CCR2+ Ly6Chigh monocytes emigrate from the bone marrow, is not required for monocyte localization to sites of bacterial infection in the liver. Expression of ICAM-1 is induced in close proximity to foci of bacterial infection in the liver, including on CD31+ endothelial cells, and blockade of CD11b and CD44 diminishes monocyte localization to these hepatic foci. Our studies demonstrated that Ly6Chigh monocyte recruitment from the bloodstream to the L. monocytogenes-infected liver does not require chemokine receptor-mediated signals but instead is principally dependent on integrin- and extracellular matrix-mediated monocyte adhesion. PMID:20435926

  20. Diminishing returns in bovine tuberculosis control.

    PubMed

    Hone, J

    2013-07-01

    Mycobacterium bovis causes bovine tuberculosis (bTB) in many mammals including cattle, deer and brushtail possum. The aim of this study was to estimate the strength of association, using model selection (AICc) regression analyses, between the proportion of cattle and farmed deer herds with bTB in New Zealand and annual costs of TB control, namely disease control in livestock, in wildlife or in a combination of the two. There was more support for curved (concave up) than linear models which related the proportion of cattle and farmed deer herds with bTB to the annual control costs. The curved, concave-up, best-fitting relationships showed diminishing returns with no positive asymptote and implied TB eradication is feasible in New Zealand. PMID:23632097

  1. Airway clearance in neuromuscular weakness.

    PubMed

    Gauld, Leanne Maree

    2009-05-01

    Impaired airway clearance leads to recurrent chest infections and respiratory deterioration in neuromuscular weakness. It is frequently the cause of death. Cough is the major mechanism of airway clearance. Cough has several components, and assessment tools are available to measure the different components of cough. These include measuring peak cough flow, respiratory muscle strength, and inspiratory capacity. Each is useful in assessing the ability to generate an effective cough, and can be used to guide when techniques of assisting airway clearance may be effective for the individual and which are most effective. Techniques to assist airway clearance include augmenting inspiration by air stacking, augmenting expiration by assisting the cough, and augmenting both inspiration and expiration with the mechanical insufflator-exsufflator or by direct suctioning via a tracheostomy. Physiotherapists are invaluable in assisting airway clearance, and in teaching patients and their families how to use these techniques. Use of the mechanical insufflator-exsufflator has gained popularity in recent times, but several simpler, more economical methods are available to assist airway clearance that can be used effectively alone or in combination. This review examines the literature available on the assessment and management of impaired airway clearance in neuromuscular weakness. PMID:19379290

  2. Dual clearance squeeze film damper

    NASA Technical Reports Server (NTRS)

    Fleming, D. P. (Inventor)

    1985-01-01

    A dual clearance hydrodynamic liquid squeeze film damper for a gas turbine engine is described. Under normal operating conditions, the device functions as a conventional squeeze film damper, using only one of its oil films. When an unbalance reaches abusive levels, as may occur with a blade loss or foreign object damage, a second, larger clearance film becomes active, controlling vibration amplitudes in a near optimum manner until the engine can be safely shut down and repaired.

  3. Method of mucociliary clearance assessment

    NASA Astrophysics Data System (ADS)

    Danilova, Tatiana V.; Manturov, Alexey O.; Ermakov, Igor Y.; Mareev, Gleb O.; Mareev, Oleg V.

    2016-04-01

    The article is devoted to the research capabilities of mucociliary clearance in the nasal cavity and paranasal sinuses using modern techniques of digital video recording and processing. We describe the setup and software for this method and the results of our research. Using microscope and digital camera we can provide a good method to study mucociliary clearance and by usage of special software we able to measure some characteristic of nasal mucosae and its main function.

  4. 14 CFR 23.925 - Propeller clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... takeoffs and landings. (c) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 23.239 can be shown with a lesser clearance. (d... airplane structure, plus any additional radial clearance necessary to prevent harmful vibration; (2)...

  5. 14 CFR 23.925 - Propeller clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... takeoffs and landings. (c) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 23.239 can be shown with a lesser clearance. (d... airplane structure, plus any additional radial clearance necessary to prevent harmful vibration; (2)...

  6. 14 CFR 23.925 - Propeller clearance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... takeoffs and landings. (c) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 23.239 can be shown with a lesser clearance. (d... airplane structure, plus any additional radial clearance necessary to prevent harmful vibration; (2)...

  7. Seasonal control of particle clearance by isolated gills from the clam Mercenaria mercenaria.

    PubMed

    Gainey, Louis F

    2007-07-01

    Pieces of gill isolated from the clam Mercenaria mercenaria clear colloidal graphite from seawater, and the clearance rates are measurable. 5-Hydroxytryptamine (5-HT) had a biphasic effect on clearance rates: concentrations from 10(-6) to 10(-5) mol l(-1) 5-HT increased clearance, but higher concentrations reduced it. During the summer, the gills were less responsive to 5-HT: the threshold increased from 1 x 10(-6) to 5 x 10(-6) mol l(-1), and although the rate was still maximal at 10(-5) mol l(-1), it was significantly lower than the maximal rate in the winter. At 10(-5) mol l(-1) 5-HT, which maximized clearance, the lateral cilia were active, the interfilament space decreased and the diameter of the water tubes increased. Higher concentrations of 5-HT contracted the gill musculature, which inhibited the lateral cilia, decreased the interfilament space even more and decreased the diameter of the water tubes. The nitric oxide (NO) generator DEANO stimulated clearance in the winter but had no effect during the summer. L-NAME, an inhibitor of NO synthesis, diminished the effect of 5-HT during the winter but was ineffective during the summer. The diminished response to 5-HT of winter gills treated with L-NAME was statistically equal to the response of the gills to 5-HT during the summer. Dopamine (DA) inhibited clearance, and the gills were more sensitive to DA in winter than in summer. Microscopic examination of untreated gills revealed little or no lateral ciliary activity, and clearance was minimal. Thus, clearance rates of isolated gills behave in a manner consistent with the seasonality and pharmacology of the lateral cilia and branchial musculature. PMID:17601956

  8. Central role for PICALM in amyloid–β blood–brain barrier transcytosis and clearance

    PubMed Central

    Zhao, Zhen; Sagare, Abhay P.; Ma, Qingyi; Halliday, Matthew R.; Kong, Pan; Kisler, Kassandra; Winkler, Ethan A.; Ramanathan, Anita; Kanekiyo, Takahisa; Bu, Guojun; Owens, Nelly Chuqui; Rege, Sanket V.; Si, Gabriel; Ahuja, Ashim; Zhu, Donghui; Miller, Carol A.; Schneider, Julie A.; Maeda, Manami; Maeda, Takahiro; Sugawara, Tohru; Ichida, Justin K.; Zlokovic, Berislav V.

    2015-01-01

    PICALM is highly validated genetic risk factor for Alzheimer’s disease (AD). Here, we report that PICALM reductions in AD and murine brain endothelium correlate with amyloid–β (Aβ) pathology and cognitive impairment. Moreover, Picalm deficiency diminishesclearance across the murine blood–brain barrier (BBB) and accelerates Aβ pathology that is reversible by endothelial PICALM re–expression. Using human brain endothelial monolayer, we show that PICALM regulates PICALM/clathrin–dependent internalization of Aβ bound to the low density lipoprotein receptor related protein–1, a key Aβ clearance receptor, and guides Aβ trafficking to Rab5 and Rab11 leading to Aβ endothelial transcytosis and clearance. PICALM levels and Aβ clearance were reduced in AD–derived endothelial monolayers, which was reversible by adenoviral–mediated PICALM transfer. iPSC–derived human endothelial cells carrying the rs3851179 protective allele exhibited higher PICALM levels and enhanced Aβ clearance. Thus, PICALM regulates Aβ BBB transcytosis and clearance that has implications for Aβ brain homeostasis and clearance therapy. PMID:26005850

  9. Central role for PICALM in amyloid-β blood-brain barrier transcytosis and clearance.

    PubMed

    Zhao, Zhen; Sagare, Abhay P; Ma, Qingyi; Halliday, Matthew R; Kong, Pan; Kisler, Kassandra; Winkler, Ethan A; Ramanathan, Anita; Kanekiyo, Takahisa; Bu, Guojun; Owens, Nelly Chuqui; Rege, Sanket V; Si, Gabriel; Ahuja, Ashim; Zhu, Donghui; Miller, Carol A; Schneider, Julie A; Maeda, Manami; Maeda, Takahiro; Sugawara, Tohru; Ichida, Justin K; Zlokovic, Berislav V

    2015-07-01

    PICALM is a highly validated genetic risk factor for Alzheimer's disease (AD). We found that reduced expression of PICALM in AD and murine brain endothelium correlated with amyloid-β (Aβ) pathology and cognitive impairment. Moreover, Picalm deficiency diminishedclearance across the murine blood-brain barrier (BBB) and accelerated Aβ pathology in a manner that was reversible by endothelial PICALM re-expression. Using human brain endothelial monolayers, we found that PICALM regulated PICALM/clathrin-dependent internalization of Aβ bound to the low density lipoprotein receptor related protein-1, a key Aβ clearance receptor, and guided Aβ trafficking to Rab5 and Rab11, leading to Aβ endothelial transcytosis and clearance. PICALM levels and Aβ clearance were reduced in AD-derived endothelial monolayers, which was reversible by adenoviral-mediated PICALM transfer. Inducible pluripotent stem cell-derived human endothelial cells carrying the rs3851179 protective allele exhibited higher PICALM levels and enhanced Aβ clearance. Thus, PICALM regulates Aβ BBB transcytosis and clearance, which has implications for Aβ brain homeostasis and clearance therapy. PMID:26005850

  10. Refrigeration system with clearance seals

    SciTech Connect

    Holland, N. J.

    1985-02-26

    In a refrigeration system such as a split Stirling system, fluid seals associated with the reciprocating displacer are virtually dragless clearance seals. Movement of the displacer relative to the pressure variations in the working volume of gas is retarded by a discrete braking element. Because it is not necessary that the brake providing any sealing action, the brake can be designed for greater durability and less dependence on ambient and operating temperatures. Similarly, the clearance seal can be formed of elements having low thermal expansion such that the seal is not temperature dependent. In the primary embodiments the braking element is a split friction brake.

  11. Inherited Disorders of Bilirubin Clearance

    PubMed Central

    Memon, Naureen; Weinberger, Barry I; Hegyi, Thomas; Aleksunes, Lauren M

    2016-01-01

    Inherited disorders of hyperbilirubinemia may be caused by increased bilirubin production or decreased bilirubin clearance. Reduced hepatic bilirubin clearance can be due to defective 1) unconjugated bilirubin uptake and intrahepatic storage, 2) conjugation of glucuronic acid to bilirubin (e.g. Gilbert syndrome, Crigler-Najjar syndrome, Lucey-Driscoll syndrome, breast milk jaundice), 3) bilirubin excretion into bile (Dubin-Johnson syndrome), or 4) conjugated bilirubin re-uptake (Rotor syndrome). In this review, the molecular mechanisms and clinical manifestations of these conditions are described, as well as current approaches to diagnosis and therapy. PMID:26595536

  12. Noninvasive clearance of airway secretions.

    PubMed

    Hardy, K A; Anderson, B D

    1996-06-01

    Airway clearance techniques are indicated for specific diseases that have known clearance abnormalities (Table 2). Murray and others have commented that such techniques are required only for patients with a daily sputum production of greater than 30 mL. The authors have observed that patients with diseases known to cause clearance abnormalities can have sputum clearance with some techniques, such as positive expiratory pressure, autogenic drainage, and active cycle of breathing techniques, when PDPV has not been effective. Hasani et al has shown that use of the forced exhalatory technique in patients with nonproductive cough still resulted in movement of secretions proximally from all regions of the lung in patients with airway obstruction. It is therefore reasonable to consider airway clearance techniques for any patient who has a disease known to alter mucous clearance, including CF, dyskinetic cilia syndromes, and bronchiectasis from any cause. Patients with atelectasis from mucous plugs and hypersecretory states, such as asthma and chronic bronchitis, patients with pain secondary to surgical procedures, and patients with neuromuscular disease, weak cough, and abnormal patency of the airway may also benefit from the application of airway clearance techniques. Infants and children up to 3 years of age with airway clearance problems need to be treated with PDPV. Manual percussion with hands alone or a flexible face mask or cup and small mechanical vibrator/percussors, such as the ultrasonic devices, can be used. The intrapulmonary percussive ventilator shows growing promise in this area. The high-frequency oscillator is not supplied with vests of appropriate sizes for tiny babies and has not been studied in this group. Young patients with neuromuscular disease may require assisted ventilation and airway oscillations can be applied. CPAP alone has been shown to improve achievable flow rates that will increase air-liquid interactions for patients with these diseases

  13. Dual-Track Clearance of Circulating Bacteria Balances Rapid Restoration of Blood Sterility with Induction of Adaptive Immunity.

    PubMed

    Broadley, Steven P; Plaumann, Ann; Coletti, Raffaele; Lehmann, Christin; Wanisch, Andreas; Seidlmeier, Amelie; Esser, Knud; Luo, Shanshan; Rämer, Patrick C; Massberg, Steffen; Busch, Dirk H; van Lookeren Campagne, Menno; Verschoor, Admar

    2016-07-13

    Efficient clearance of bacteremia prevents life-threatening disease. Platelet binding to intravascular bacteria, a process involving platelet glycoprotein GPIb and bacterial opsonization with activated complement C3, influences blood clearance and anti-infective immunity. Using intravital microscopy of the bloodstream of mice infected with Listeria monocytogenes, we show that bacterial clearance is not a uniform process but a "dual-track" mechanism consisting of parallel "fast" and "slow" pathways. "Slow clearance" is regulated by time-dependent bacterial opsonization, stochastic platelet binding, and capture of bacteria-platelet-complexes via the complement receptor of the immunoglobulin superfamily, CRIg. The mechanism spares some bacteria from "fast clearance" and rapid destruction in the liver via Kupffer cell scavenger receptors, keeping them available for adaptive immunity induction by splenic CD8α(+) dendritic cells. We consistently find "fast" and "slow" clearance patterns for a broad panel of other Gram+ and Gram- bacteria. Thus, dual-track clearance balances rapid restoration of blood sterility with induction of specific antibacterial immunity. PMID:27345696

  14. Microwave Blade Tip Clearance System: An Update

    NASA Technical Reports Server (NTRS)

    Geisheimer, Jon

    2006-01-01

    Newer engines use compressor bleed air and a model to close clearances open loop. Measuring clearances and closing the control loop can add additional efficiencies. Tip clearance control has been identified as a key technology for future engines Additional benefits in prognostics, NSMS, and condition-based maintenance. In the HPT for every 1 mil improvement in clearance: a) SFC decreases 0.1%; and b) EGT margin increases 1 C.

  15. The Dynamics of Apoptotic Cell Clearance.

    PubMed

    Elliott, Michael R; Ravichandran, Kodi S

    2016-07-25

    The phagocytic clearance of dying cells in a tissue is a highly orchestrated series of intercellular events coordinated by a complex signaling network. Recent data from genetic, biochemical, and live-imaging approaches have greatly enhanced our understanding of the dynamics of cell clearance and how the process is orchestrated at the cellular and tissue levels. We discuss how networks regulating apoptotic cell clearance are integrated to enable a rapid, efficient, and high-capacity clearance system within tissues. PMID:27459067

  16. 22 CFR 16.6 - Security clearances.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Security clearances. 16.6 Section 16.6 Foreign Relations DEPARTMENT OF STATE PERSONNEL FOREIGN SERVICE GRIEVANCE SYSTEM § 16.6 Security clearances. The agencies shall use their best endeavors to expedite security clearances whenever necessary to ensure a...

  17. 49 CFR 192.325 - Underground clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Underground clearance. 192.325 Section 192.325... Lines and Mains § 192.325 Underground clearance. (a) Each transmission line must be installed with at least 12 inches (305 millimeters) of clearance from any other underground structure not associated...

  18. 30 CFR 18.24 - Electrical clearances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  19. 30 CFR 18.24 - Electrical clearances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  20. 30 CFR 18.24 - Electrical clearances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  1. 30 CFR 18.24 - Electrical clearances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  2. 30 CFR 18.24 - Electrical clearances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical clearances. 18.24 Section 18.24... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical...

  3. 29 CFR 1917.113 - Clearance heights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Clearance heights. 1917.113 Section 1917.113 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.113 Clearance heights. Clearance heights shall...

  4. 30 CFR 56.11010 - Stairstep clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Stairstep clearance. 56.11010 Section 56.11010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Travelways § 56.11010 Stairstep clearance. Vertical clearance...

  5. 14 CFR 25.925 - Propeller clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the corresponding landing gear strut bottomed. (b) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 25.239(a) can be shown... to prevent harmful vibration; (2) At least one-half inch longitudinal clearance between the...

  6. 14 CFR 25.925 - Propeller clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the corresponding landing gear strut bottomed. (b) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 25.239(a) can be shown... to prevent harmful vibration; (2) At least one-half inch longitudinal clearance between the...

  7. 14 CFR 25.925 - Propeller clearance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the corresponding landing gear strut bottomed. (b) Water clearance. There must be a clearance of at least 18 inches between each propeller and the water, unless compliance with § 25.239(a) can be shown... to prevent harmful vibration; (2) At least one-half inch longitudinal clearance between the...

  8. 33 CFR 117.47 - Clearance gauges.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Clearance gauges. 117.47 Section 117.47 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS General Requirements § 117.47 Clearance gauges. (a) Clearance gauges are required for drawbridges across navigable waters...

  9. 33 CFR 117.47 - Clearance gauges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Clearance gauges. 117.47 Section 117.47 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS General Requirements § 117.47 Clearance gauges. (a) Clearance gauges are required for drawbridges across navigable waters...

  10. 33 CFR 117.47 - Clearance gauges.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Clearance gauges. 117.47 Section 117.47 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS General Requirements § 117.47 Clearance gauges. (a) Clearance gauges are required for drawbridges across navigable waters...

  11. 33 CFR 117.47 - Clearance gauges.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Clearance gauges. 117.47 Section 117.47 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS General Requirements § 117.47 Clearance gauges. (a) Clearance gauges are required for drawbridges across navigable waters...

  12. 22 CFR 16.6 - Security clearances.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Security clearances. 16.6 Section 16.6 Foreign Relations DEPARTMENT OF STATE PERSONNEL FOREIGN SERVICE GRIEVANCE SYSTEM § 16.6 Security clearances. The agencies shall use their best endeavors to expedite security clearances whenever necessary to ensure a...

  13. 22 CFR 16.6 - Security clearances.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Security clearances. 16.6 Section 16.6 Foreign Relations DEPARTMENT OF STATE PERSONNEL FOREIGN SERVICE GRIEVANCE SYSTEM § 16.6 Security clearances. The agencies shall use their best endeavors to expedite security clearances whenever necessary to ensure a...

  14. 22 CFR 16.6 - Security clearances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Security clearances. 16.6 Section 16.6 Foreign Relations DEPARTMENT OF STATE PERSONNEL FOREIGN SERVICE GRIEVANCE SYSTEM § 16.6 Security clearances. The agencies shall use their best endeavors to expedite security clearances whenever necessary to ensure a...

  15. 29 CFR 1917.113 - Clearance heights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Clearance heights. 1917.113 Section 1917.113 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.113 Clearance heights. Clearance heights shall be prominently posted where the height is insufficient for vehicles and equipment....

  16. 29 CFR 1917.113 - Clearance heights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Clearance heights. 1917.113 Section 1917.113 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.113 Clearance heights. Clearance heights shall be prominently posted where the height is insufficient for vehicles and equipment....

  17. 29 CFR 1917.113 - Clearance heights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Clearance heights. 1917.113 Section 1917.113 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.113 Clearance heights. Clearance heights shall be prominently posted where the height is insufficient for vehicles and equipment....

  18. 29 CFR 1917.113 - Clearance heights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Clearance heights. 1917.113 Section 1917.113 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.113 Clearance heights. Clearance heights shall...

  19. Removal - An alternative to clearance

    SciTech Connect

    Feinhals, J.; Kelch, A.; Kunze, V.

    2007-07-01

    This presentation shows the differences between the application of clearance and removal, both being procedures for materials leaving radiation protection areas permanently. The differentiation will be done on the basis of the German legislation but may be also applicable for other national legislation. For clearance in Germany two basic requirements must be given, i.e. that the materials are activated or contaminated and that they result from the licensed use or can be assigned to the scope of the license. Clearance needs not to be applied to objects in Germany which are to be removed only temporarily from controlled areas with the purpose of repair or reuse in other controlled areas. In these cases only the requirements of contamination control apply. In the case of removal it must either be proved by measurements that the relevant materials are neither activated nor contaminated or that the materials result from areas where activation or contamination is impossible due to the operational history considering operational procedures and events. If the material is considered neither activated nor contaminated there is no need for a clearance procedure. Therefore, these materials can be removed from radiation protection areas and the removal is in the responsibility of the licensee. Nevertheless, the removal procedure and the measuring techniques to be applied for the different types of materials need an agreement from the competent authority. In Germany a maximum value of 10% of the clearance values has been established in different licenses as a criterion for the application of removal. As approximately 2/3 of the total mass of a nuclear power plant is not expected to be contaminated or activated there is a need for such a procedure of removal for this non contaminated material without any regulatory control especially in the case of decommissioning. A remarkable example is NPP Stade where in the last three years more than 8600 Mg were disposed of by removal and

  20. The airborne survival of Pasteurella haemolytica and its deposition in and clearance from the mouse lung.

    PubMed

    Gilmour, M I; Wathes, C M; Taylor, F G

    1990-02-01

    Pasteurella haemolytica A1 was aerosolised by a Collison nebuliser in a Henderson apparatus and its survival in air was measured. The organism was fragile in aerosol and survived best at high humidity and warm temperature. Mice were exposed to the aerosol and clearance from the lung measured. Deposition in the mouse lung showed a good linear correlation with bacterial concentration in the spray suspension fluid. Clearance from the lung was rapid over 24 h although some bacteria could be detected 2 and 4 days after exposure. Mice which received a second exposure 2 weeks later exhibited accelerated clearance from the lung whereby no bacteria could be detected after 12 h. This was associated with serum IgG antibody production, and local and splenic lymphocyte responses to bacterial antigen in vitro. PMID:2138372

  1. Effects of dipyridamole-induced vasodilation on myocardial uptake and clearance kinetics of thallium-201

    SciTech Connect

    Beller, G.A.; Holzgrefe, H.H.; Watson, D.D.

    1983-12-01

    Myocardial thallium-201 (201Tl) uptake and clearance after intravenous administration of dipyridamole (150 micrograms/kg) were determined in 12 open-chest anesthetized dogs with a partial coronary artery stenosis. 201Tl (1.5 mCi) was injected intravenously and myocardial biopsy specimens were obtained 10 min, 60 min, and 2 hr after injection. Serial changes in 201Tl activity in the normal zone and in the zone of partial stenosis were correlated with microsphere-determined regional blood flow and distal coronary pressure. Another nine dogs with equivalent stenosis not given dipyridamole before 201Tl served as controls. Data indicate that dipyridamole-induced vasodilation in the presence of a partial stenosis results in diminished uptake and delayed clearance compared with increased uptake and more rapid clearance in normally perfused myocardium producing an initial 201Tl defect with delayed redistribution.

  2. MicroRNA-155 Is Required for Clearance of Streptococcus pneumoniae from the Nasopharynx

    PubMed Central

    Verschoor, Chris P.; Dorrington, Michael G.; Novakowski, Kyle E.; Kaiser, Julie; Radford, Katherine; Nair, Parameswaran; Anipindi, Varun; Kaushic, Charu; Surette, Michael G.

    2014-01-01

    Pneumonia caused by Streptococcus pneumoniae is a major cause of death and an economic burden worldwide. S. pneumoniae is an intermittent colonizer of the human upper respiratory tract, and the ability to control asymptomatic colonization determines the likelihood of developing invasive disease. Recognition of S. pneumoniae by resident macrophages via Toll-like receptor 2 (TLR-2) and the macrophage receptor with collagenous structure (MARCO) and the presence of interleukin-17 (IL-17)-secreting CD4+ T cells are required for macrophage recruitment and bacterial clearance. Despite the fact that the primary cellular effectors needed for bacterial clearance have been identified, much of the underlying regulatory mechanisms are unknown. Herein, we demonstrate that the small, noncoding RNA microRNA-155 (mir-155) is critical for the effective clearance of S. pneumoniae. Our studies show that mir-155-deficient mice maintain the ability to prevent acute invasive pneumococcal infection but have significantly higher bacterial burdens following colonization, independently of macrophage recognition by TLR-2, MARCO expression, or bactericidal capacity. The observed defects in bacterial clearance parallel reduced IL-17A and gamma interferon CD4+ T-cell responses in vivo, lower IL-17A mRNA levels in the nasopharynx, and a reduced capacity to induce Th17 cell polarization. Given that knockout mice are also limited in the capacity to generate high-titer S. pneumoniae-specific antibodies, we conclude that mir-155 is a critical mediator of the cellular effectors needed to clear primary and secondary S. pneumoniae colonizations. PMID:25156727

  3. Interventions for control of Salmonella: Clearance of Microbial growth from rubber picker fingers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine if a surface material with antimicrobial properties combined with an effective disinfectant could achieve total clearance of bacterial contamination. Prior to beginning the project, new rubber picker fingers collected from three processing facilities were tested fo...

  4. Prediction of drug clearance in children.

    PubMed

    Foissac, Frantz; Bouazza, Naïm; Valade, Elodie; De Sousa Mendes, Mailys; Fauchet, Floris; Benaboud, Sihem; Hirt, Déborah; Tréluyer, Jean-Marc; Urien, Saïk

    2015-07-01

    The pediatric population is often exposed to drugs without sufficient knowledge about pharmacokinetics. The prediction of accurate clearance values in children, especially in neonates and infants, will improve the rational in dosing decisions. Drug clearances from birth to adulthood were compiled after a systematic review of pharmacokinetic reports. The analysis was performed using NONMEM. Clearance predictions were then evaluated by external validation. Prediction errors were also compared with those obtained from weight-based allometric scaling and physiologically based clearance (PBCL) models. For the analysis, 17 and 15 drugs were used for model building and external validation, respectively. A model based on the adult drug clearance value and taking into account both weight and age was retained. Age-related maturation of clearance reached 90% of the adult value within 1.5 years of life. For children less than 2 years old, allometric scaling alone systematically overestimated clearances. Accounting for age improved the clearance prediction in the 6 months-2 years age group (prediction error < 25%). Predictions obtained from the PBCL approach were close to our results. This analysis established a single equation using the adult clearance value as well as individual age and weight to predict drug clearance in children older than 6 months. PMID:25721251

  5. Necroptosis Promotes Staphylococcus aureus Clearance by Inhibiting Excessive Inflammatory Signaling.

    PubMed

    Kitur, Kipyegon; Wachtel, Sarah; Brown, Armand; Wickersham, Matthew; Paulino, Franklin; Peñaloza, Hernán F; Soong, Grace; Bueno, Susan; Parker, Dane; Prince, Alice

    2016-08-23

    Staphylococcus aureus triggers inflammation through inflammasome activation and recruitment of neutrophils, responses that are critical for pathogen clearance but are associated with substantial tissue damage. We postulated that necroptosis, cell death mediated by the RIPK1/RIPK3/MLKL pathway, would function to limit pathological inflammation. In models of skin infection or sepsis, Mlkl-/- mice had high bacterial loads, an inability to limit interleukin-1b (IL-1b) production, and excessive inflammation. Similarly, mice treated with RIPK1 or RIPK3 inhibitors had increased bacterial loads in a model of sepsis. Ripk3-/- mice exhibited increased staphylococcal clearance and decreased inflammation in skin and systemic infection, due to direct effects of RIPK3 on IL-1b activation and apoptosis. In contrast to Casp1/4-/- mice with defective S. aureus killing, the poor outcomes of Mlkl-/- mice could not be attributed to impaired phagocytic function. We conclude that necroptotic cell death limits the pathological inflammation induced by S. aureus. PMID:27524612

  6. Neutrophils mediate Salmonella Typhimurium clearance through the GBP4 inflammasome-dependent production of prostaglandins

    PubMed Central

    Tyrkalska, Sylwia D.; Candel, Sergio; Angosto, Diego; Gómez-Abellán, Victoria; Martín-Sánchez, Fátima; García-Moreno, Diana; Zapata-Pérez, Rubén; Sánchez-Ferrer, Álvaro; Sepulcre, María P.; Pelegrín, Pablo; Mulero, Victoriano

    2016-01-01

    Inflammasomes are cytosolic molecular platforms that alert the immune system about the presence of infection. Here we report that zebrafish guanylate-binding protein 4 (Gbp4), an IFNγ-inducible GTPase protein harbouring a C-terminal CARD domain, is required for the inflammasome-dependent clearance of Salmonella Typhimurium (ST) by neutrophils in vivo. Despite the presence of the CARD domain, Gbp4 requires the universal inflammasome adaptor Asc for mediating its antibacterial function. In addition, the GTPase activity of Gbp4 is indispensable for inflammasome activation and ST clearance. Mechanistically, neutrophils are recruited to the infection site through the inflammasome-independent production of the chemokine (CXC motif) ligand 8 and leukotriene B4, and then mediate bacterial clearance through the Gbp4 inflammasome-dependent biosynthesis of prostaglandin D2. Our results point to GBPs as key inflammasome adaptors required for prostaglandin biosynthesis and bacterial clearance by neutrophils and suggest that transient activation of the inflammasome may be used to treat bacterial infections. PMID:27363812

  7. Neutrophils mediate Salmonella Typhimurium clearance through the GBP4 inflammasome-dependent production of prostaglandins.

    PubMed

    Tyrkalska, Sylwia D; Candel, Sergio; Angosto, Diego; Gómez-Abellán, Victoria; Martín-Sánchez, Fátima; García-Moreno, Diana; Zapata-Pérez, Rubén; Sánchez-Ferrer, Álvaro; Sepulcre, María P; Pelegrín, Pablo; Mulero, Victoriano

    2016-01-01

    Inflammasomes are cytosolic molecular platforms that alert the immune system about the presence of infection. Here we report that zebrafish guanylate-binding protein 4 (Gbp4), an IFNγ-inducible GTPase protein harbouring a C-terminal CARD domain, is required for the inflammasome-dependent clearance of Salmonella Typhimurium (ST) by neutrophils in vivo. Despite the presence of the CARD domain, Gbp4 requires the universal inflammasome adaptor Asc for mediating its antibacterial function. In addition, the GTPase activity of Gbp4 is indispensable for inflammasome activation and ST clearance. Mechanistically, neutrophils are recruited to the infection site through the inflammasome-independent production of the chemokine (CXC motif) ligand 8 and leukotriene B4, and then mediate bacterial clearance through the Gbp4 inflammasome-dependent biosynthesis of prostaglandin D2. Our results point to GBPs as key inflammasome adaptors required for prostaglandin biosynthesis and bacterial clearance by neutrophils and suggest that transient activation of the inflammasome may be used to treat bacterial infections. PMID:27363812

  8. Acute Bacterial Cholangitis

    PubMed Central

    Zimmer, Vincent; Lammert, Frank

    2015-01-01

    Background Acute bacterial cholangitis for the most part owing to common bile duct stones is common in gastroenterology practice and represents a potentially life-threatening condition often characterized by fever, abdominal pain, and jaundice (Charcot's triad) as well as confusion and septic shock (Reynolds' pentad). Methods This review is based on a systematic literature review in PubMed with the search items ‘cholangitis’, ‘choledocholithiasis’, ‘gallstone disease’, ‘biliary infection’, and ‘biliary sepsis’. Results Although most patients respond to empiric broad-spectrum antibiotic treatment, timely endoscopic biliary drainage depending on the severity of the disease is required to eliminate the underlying obstruction. Specific recommendations have been derived from the Tokyo guideline working group consensus 2006 and its update in 2013, albeit poorly evidence-based, providing a comprehensive overview of diagnosis, classification, risk stratification, and treatment algorithms in acute bacterial cholangitis. Conclusion Prompt clinical recognition and accurate diagnostic workup including adequate laboratory assessment and (aetiology-oriented) imaging are critical steps in the management of cholangitis. Treatment is directed at the two major interrelated pathophysiologic components, i.e. bacterial infection (immediate antimicrobial therapy) and bile duct obstruction (biliary drainage). As for the latter, transpapillary endoscopic drainage by stent or nasobiliary drain and/or same-session bile duct clearance, depending on individual disease severity, represent first-line treatment approaches. PMID:26468310

  9. Bacterial Sialidase

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Data shows that elevated sialidase in bacterial vaginosis patients correlates to premature births in women. Bacterial sialidase also plays a significant role in the unusual colonization of Pseudomonas aeruginosa in cystic fibrosis patients. Crystals of Salmonella sialidase have been reproduced and are used for studying the inhibitor-enzyme complexes. These inhibitors may also be used to inhibit a trans-sialidase of Trypanosome cruzi, a very similar enzyme to bacterial sialidase, therefore preventing T. cruzi infection, the causitive agent of Chagas' disease. The Center for Macromolecular Crystallography suggests that inhibitors of bacterial sialidases can be used as prophylactic drugs to prevent bacterial infections in these critical cases.

  10. Diminishing Adult Egocentrism when Estimating What Others Know

    ERIC Educational Resources Information Center

    Thomas, Ruthann C.; Jacoby, Larry L.

    2013-01-01

    People often use what they know as a basis to estimate what others know. This egocentrism can bias their estimates of others' knowledge. In 2 experiments, we examined whether people can diminish egocentrism when predicting for others. Participants answered general knowledge questions and then estimated how many of their peers would know the…

  11. The Changing Black Teacher and Diminishing Opportunities for Black Teachers.

    ERIC Educational Resources Information Center

    Hilliard, Asa G., III

    Racism remains a distinct factor in problems faced by black teachers and teacher educators. The number of black teachers in the public schools is diminishing, especially in the southern states, where the black student population is the highest. The higher education environment has been undergoing drastic changes in faculty and student body…

  12. Innate Lymphocyte/Ly6C(hi) Monocyte Crosstalk Promotes Klebsiella Pneumoniae Clearance.

    PubMed

    Xiong, Huizhong; Keith, James W; Samilo, Dane W; Carter, Rebecca A; Leiner, Ingrid M; Pamer, Eric G

    2016-04-21

    Increasing antibiotic resistance among bacterial pathogens has rendered some infections untreatable with available antibiotics. Klebsiella pneumoniae, a bacterial pathogen that has acquired high-level antibiotic resistance, is a common cause of pulmonary infections. Optimal clearance of K. pneumoniae from the host lung requires TNF and IL-17A. Herein, we demonstrate that inflammatory monocytes are rapidly recruited to the lungs of K. pneumoniae-infected mice and produce TNF, which markedly increases the frequency of IL-17-producing innate lymphoid cells. While pulmonary clearance of K. pneumoniae is preserved in neutrophil-depleted mice, monocyte depletion or TNF deficiency impairs IL-17A-dependent resolution of pneumonia. Monocyte-mediated bacterial uptake and killing is enhanced by ILC production of IL-17A, indicating that innate lymphocytes engage in a positive-feedback loop with monocytes that promotes clearance of pneumonia. Innate immune defense against a highly antibiotic-resistant bacterial pathogen depends on crosstalk between inflammatory monocytes and innate lymphocytes that is mediated by TNF and IL-17A. PMID:27040495

  13. AHERA CLEARANCE AT TWENTY ABATEMENT SITES

    EPA Science Inventory

    A study was conducted during the summer of 1988 to document Asbestos Hazard Emergency Response Act (AHERA) clearance air sampling practices and clearance concentrations of airborne asbestos at 20 asbestos-abatement sites in New Jersey. ach abatement took place in a school buildin...

  14. AHERA CLEARANCE AT TWENTY ABATEMENT SITES

    EPA Science Inventory

    A study was conducted during the summer of 1988 to document Asbestos Hazard Emergency Response Act (AHERA) clearance air-sampling practices and clearance concentrations of airborne asbestos at 20 asbestos-abatement sites in New Jersey. Each abatement took place in a school buildi...

  15. 14 CFR 25.925 - Propeller clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... nose wheel landing gear) or nine inches (for each airplane with tail wheel landing gear) between each propeller and the ground with the landing gear statically deflected and in the level takeoff, or taxiing... the corresponding landing gear strut bottomed. (b) Water clearance. There must be a clearance of...

  16. 14 CFR 25.925 - Propeller clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... nose wheel landing gear) or nine inches (for each airplane with tail wheel landing gear) between each propeller and the ground with the landing gear statically deflected and in the level takeoff, or taxiing... the corresponding landing gear strut bottomed. (b) Water clearance. There must be a clearance of...

  17. 19 CFR 122.77 - Clearance certificate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Departing From the United States § 122.77 Clearance certificate. (a) Aircraft departing from the U.S. One... director to show that clearance is granted. (b) Scheduled aircraft. If a scheduled aircraft clears at...

  18. 19 CFR 122.77 - Clearance certificate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Departing From the United States § 122.77 Clearance certificate. (a) Aircraft departing from the U.S. One... director to show that clearance is granted. (b) Scheduled aircraft. If a scheduled aircraft clears at...

  19. 19 CFR 122.77 - Clearance certificate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Departing From the United States § 122.77 Clearance certificate. (a) Aircraft departing from the U.S. One... director to show that clearance is granted. (b) Scheduled aircraft. If a scheduled aircraft clears at...

  20. 19 CFR 122.77 - Clearance certificate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Departing From the United States § 122.77 Clearance certificate. (a) Aircraft departing from the U.S. One... director to show that clearance is granted. (b) Scheduled aircraft. If a scheduled aircraft clears at...

  1. 30 CFR 56.11008 - Restricted clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Restricted clearance. 56.11008 Section 56.11008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Travelways § 56.11008 Restricted clearance. Where...

  2. 49 CFR 192.325 - Underground clearance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Lines and Mains § 192.325 Underground clearance. (a) Each transmission line must be installed with at... the transmission line. If this clearance cannot be attained, the transmission line must be protected... the requirements of paragraph (a) or (b) of this section, each plastic transmission line or main...

  3. 49 CFR 192.325 - Underground clearance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Lines and Mains § 192.325 Underground clearance. (a) Each transmission line must be installed with at... the transmission line. If this clearance cannot be attained, the transmission line must be protected... the requirements of paragraph (a) or (b) of this section, each plastic transmission line or main...

  4. 49 CFR 192.325 - Underground clearance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Lines and Mains § 192.325 Underground clearance. (a) Each transmission line must be installed with at... the transmission line. If this clearance cannot be attained, the transmission line must be protected... the requirements of paragraph (a) or (b) of this section, each plastic transmission line or main...

  5. 24 CFR 35.1340 - Clearance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... abatement of lead-based paint or lead-based paint hazards shall be performed in accordance with 40 CFR 745... the steps set forth at 40 CFR 745.227(e)(8). If clearance is being performed after lead-based paint... certified to perform risk assessments or lead-based paint inspections. (b) Clearance following...

  6. 24 CFR 35.1340 - Clearance.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... abatement of lead-based paint or lead-based paint hazards shall be performed in accordance with 40 CFR 745... the steps set forth at 40 CFR 745.227(e)(8). If clearance is being performed after lead-based paint... certified to perform risk assessments or lead-based paint inspections. (b) Clearance following...

  7. 24 CFR 35.1340 - Clearance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... abatement of lead-based paint or lead-based paint hazards shall be performed in accordance with 40 CFR 745... the steps set forth at 40 CFR 745.227(e)(8). If clearance is being performed after lead-based paint... certified to perform risk assessments or lead-based paint inspections. (b) Clearance following...

  8. 24 CFR 35.1340 - Clearance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... abatement of lead-based paint or lead-based paint hazards shall be performed in accordance with 40 CFR 745... the steps set forth at 40 CFR 745.227(e)(8). If clearance is being performed after lead-based paint... certified to perform risk assessments or lead-based paint inspections. (b) Clearance following...

  9. 19 CFR 122.77 - Clearance certificate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Clearance certificate. 122.77 Section 122.77 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Documents Required for Clearance and Permission To Depart;...

  10. 30 CFR 56.7018 - Hand clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand clearance. 56.7018 Section 56.7018 Mineral... Drilling § 56.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling....

  11. 30 CFR 56.7018 - Hand clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand clearance. 56.7018 Section 56.7018 Mineral... Drilling § 56.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling....

  12. 30 CFR 56.7018 - Hand clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand clearance. 56.7018 Section 56.7018 Mineral... Drilling § 56.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling....

  13. 30 CFR 56.7018 - Hand clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand clearance. 56.7018 Section 56.7018 Mineral... Drilling § 56.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling....

  14. 30 CFR 57.7018 - Hand clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand clearance. 57.7018 Section 57.7018 Mineral... Drilling-Surface Only § 57.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling. Drilling—Underground Only...

  15. 30 CFR 57.7028 - Hand clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand clearance. 57.7028 Section 57.7028 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Drilling-Underground Only § 57.7028 Hand clearance. Persons shall not rest their hands on the chuck...

  16. 30 CFR 57.7028 - Hand clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand clearance. 57.7028 Section 57.7028 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Drilling-Underground Only § 57.7028 Hand clearance. Persons shall not rest their hands on the chuck...

  17. 30 CFR 57.7018 - Hand clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand clearance. 57.7018 Section 57.7018 Mineral... Drilling-Surface Only § 57.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling. Drilling—Underground Only...

  18. 30 CFR 57.7028 - Hand clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand clearance. 57.7028 Section 57.7028 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Drilling-Underground Only § 57.7028 Hand clearance. Persons shall not rest their hands on the chuck...

  19. 30 CFR 57.7018 - Hand clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand clearance. 57.7018 Section 57.7018 Mineral... Drilling-Surface Only § 57.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling. Drilling—Underground Only...

  20. 30 CFR 57.7028 - Hand clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand clearance. 57.7028 Section 57.7028 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Drilling-Underground Only § 57.7028 Hand clearance. Persons shall not rest their hands on the chuck...

  1. 30 CFR 57.7018 - Hand clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand clearance. 57.7018 Section 57.7018 Mineral... Drilling-Surface Only § 57.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling. Drilling—Underground Only...

  2. 30 CFR 57.7028 - Hand clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand clearance. 57.7028 Section 57.7028 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Drilling-Underground Only § 57.7028 Hand clearance. Persons shall not rest their hands on the chuck...

  3. 30 CFR 57.7018 - Hand clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand clearance. 57.7018 Section 57.7018 Mineral... Drilling-Surface Only § 57.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling. Drilling—Underground Only...

  4. 30 CFR 56.7018 - Hand clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand clearance. 56.7018 Section 56.7018 Mineral... Drilling § 56.7018 Hand clearance. Persons shall not hold the drill steel while collaring holes, or rest their hands on the chuck or centralizer while drilling....

  5. 32 CFR 154.16 - Security clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... be processed for a security clearance in accordance with 32 CFR part 353 and the provisions of this... shall be accomplished in accordance with 32 CFR part 159. The investigative requirement shall be the... 32 National Defense 1 2014-07-01 2014-07-01 false Security clearance. 154.16 Section...

  6. 32 CFR 154.16 - Security clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be processed for a security clearance in accordance with 32 CFR part 353 and the provisions of this... shall be accomplished in accordance with 32 CFR part 159. The investigative requirement shall be the... 32 National Defense 1 2010-07-01 2010-07-01 false Security clearance. 154.16 Section...

  7. 32 CFR 154.16 - Security clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... be processed for a security clearance in accordance with 32 CFR part 353 and the provisions of this... shall be accomplished in accordance with 32 CFR part 159. The investigative requirement shall be the... 32 National Defense 1 2012-07-01 2012-07-01 false Security clearance. 154.16 Section...

  8. Intelligent Engine Systems: HPT Clearance Control

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Advanced Thermally Actuated Clearance Control System underwent several studies. Improved flow path isolation quantified what can be gained by making the HPT case nearly adiabatic. The best method of heat transfer was established, and finally two different borrowed air cooling circuits were evaluated to be used for the HPT Active Clearance Control System.

  9. Diminished Macrophage Apoptosis and Reactive Oxygen Species Generation after Phorbol Ester Stimulation in Crohn's Disease

    PubMed Central

    Palmer, Christine D.; Rahman, Farooq Z.; Sewell, Gavin W.; Ahmed, Afshan; Ashcroft, Margaret; Bloom, Stuart L.; Segal, Anthony W.; Smith, Andrew M.

    2009-01-01

    Background Crohn's Disease (CD) is a chronic relapsing disorder characterized by granulomatous inflammation of the gastrointestinal tract. Although its pathogenesis is complex, we have recently shown that CD patients have a systemic defect in macrophage function, which results in the defective clearance of bacteria from inflammatory sites. Methodology/Principal Findings Here we have identified a number of additional macrophage defects in CD following diacylglycerol (DAG) homolog phorbol-12-myristate-13-acetate (PMA) activation. We provide evidence for decreased DNA fragmentation, reduced mitochondrial membrane depolarization, impaired reactive oxygen species production, diminished cytochrome c release and increased IL-6 production compared to healthy subjects after PMA exposure. The observed macrophage defects in CD were stimulus-specific, as normal responses were observed following p53 activation and endoplasmic reticulum stress. Conclusion These findings add to a growing body of evidence highlighting disordered macrophage function in CD and, given their pivotal role in orchestrating inflammatory responses, defective apoptosis could potentially contribute to the pathogenesis of CD. PMID:19907654

  10. Xenon spill distribution and room clearance.

    PubMed

    Kelsey, C A; Telepak, R J

    1999-11-01

    The purpose of these studies was to investigate actual xenon gas clearance times under different exhaust conditions, to compare them with the calculated clearance times, to observe the distribution of the xenon gas while it was being exhausted from the room, and to determine the cause of a stationary xenon cloud that appeared on some clinical images. Clearance times with and without a flexible exhaust hose placed next to a simulated 133Xe gas spill were compared with clearance times measured in a room with all exhaust closed off. Two gamma cameras were used to observe the transport and exhaust of xenon following a simulated spill. Clearance times with the flexible exhaust hose were less than one minute because the xenon gas was removed before it had a chance to disperse into the room. Conventional room clearance calculations based on uniform mixing and measured exhaust rates yielded a clearance time of 22 min. The source of an artifactual stationary cloud image was discovered to be a small amount of xenon trapped between the collimator and camera face. A negative pressure and dedicated exhaust can be even more effective in exhausting spilled xenon from a room than air transfer calculations predict. The authors believe the flexible hose should always be used. PMID:10524516

  11. Bacterial Proteasomes

    PubMed Central

    Jastrab, Jordan B.; Darwin, K. Heran

    2015-01-01

    Interest in bacterial proteasomes was sparked by the discovery that proteasomal degradation is required for the pathogenesis of Mycobacterium tuberculosis, one of the world's deadliest pathogens. Although bacterial proteasomes are structurally similar to their eukaryotic and archaeal homologs, there are key differences in their mechanisms of assembly, activation, and substrate targeting for degradation. In this article, we compare and contrast bacterial proteasomes with their archaeal and eukaryotic counterparts, and we discuss recent advances in our understanding of how bacterial proteasomes function to influence microbial physiology. PMID:26488274

  12. Metabolic reprogramming induced by ketone bodies diminishes pancreatic cancer cachexia

    PubMed Central

    2014-01-01

    Background Aberrant energy metabolism is a hallmark of cancer. To fulfill the increased energy requirements, tumor cells secrete cytokines/factors inducing muscle and fat degradation in cancer patients, a condition known as cancer cachexia. It accounts for nearly 20% of all cancer-related deaths. However, the mechanistic basis of cancer cachexia and therapies targeting cancer cachexia thus far remain elusive. A ketogenic diet, a high-fat and low-carbohydrate diet that elevates circulating levels of ketone bodies (i.e., acetoacetate, β-hydroxybutyrate, and acetone), serves as an alternative energy source. It has also been proposed that a ketogenic diet leads to systemic metabolic changes. Keeping in view the significant role of metabolic alterations in cancer, we hypothesized that a ketogenic diet may diminish glycolytic flux in tumor cells to alleviate cachexia syndrome and, hence, may provide an efficient therapeutic strategy. Results We observed reduced glycolytic flux in tumor cells upon treatment with ketone bodies. Ketone bodies also diminished glutamine uptake, overall ATP content, and survival in multiple pancreatic cancer cell lines, while inducing apoptosis. A decrease in levels of c-Myc, a metabolic master regulator, and its recruitment on glycolytic gene promoters, was in part responsible for the metabolic phenotype in tumor cells. Ketone body-induced intracellular metabolomic reprogramming in pancreatic cancer cells also leads to a significantly diminished cachexia in cell line models. Our mouse orthotopic xenograft models further confirmed the effect of a ketogenic diet in diminishing tumor growth and cachexia. Conclusions Thus, our studies demonstrate that the cachectic phenotype is in part due to metabolic alterations in tumor cells, which can be reverted by a ketogenic diet, causing reduced tumor growth and inhibition of muscle and body weight loss. PMID:25228990

  13. Oxygen radicals diminish dopamine transporter function in rat striatum.

    PubMed

    Fleckenstein, A E; Metzger, R R; Beyeler, M L; Gibb, J W; Hanson, G R

    1997-09-01

    Incubation of striatal synaptosomes with the oxygen radical generating enzyme, xanthine oxidase, decreased [3H]dopamine uptake: an effect attributable to a decreased Vmax. Concurrent incubation with the superoxide radical scavenger, superoxide dismutase, abolished the xanthine oxidase-induced decrease. These results indicate that, like methamphetamine administration in vivo, reactive oxygen species diminish dopamine transporter function in vitro. The significance of these findings to mechanisms responsible for effects of methamphetamine is discussed. PMID:9346337

  14. Diminished Reality Based on Image Inpainting Considering Background Geometry.

    PubMed

    Kawai, Norihiko; Sato, Tomokazu; Yokoya, Naokazu

    2016-03-01

    Diminished reality aims to remove real objects from video images and fill in the missing regions with plausible background textures in real time. Most conventional methods based on image inpainting achieve diminished reality by assuming that the background around a target object is almost planar. This paper proposes a new diminished reality method that considers background geometries with less constraints than the conventional ones. In this study, we approximate the background geometry by combining local planes, and improve the quality of image inpainting by correcting the perspective distortion of texture and limiting the search area for finding similar textures as exemplars. The temporal coherence of texture is preserved using the geometries and camera pose estimated by visual-simultaneous localization and mapping (SLAM). The mask region that includes a target object is robustly set in each frame by projecting a 3D region, rather than tracking the object in 2D image space. The effectiveness of the proposed method is successfully demonstrated using several experimental environments. PMID:26829239

  15. Advanced optical blade tip clearance measurement system

    NASA Technical Reports Server (NTRS)

    Ford, M. J.; Honeycutt, R. E.; Nordlund, R. E.; Robinson, W. W.

    1978-01-01

    An advanced electro-optical system was developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in an operating gas turbine engine. This system is applicable to fan, compressor, and turbine blade tip clearance measurement requirements, and the system probe is particularly suitable for operation in the extreme turbine environment. A study of optical properties of blade tips was conducted to establish measurement system application limitations. A series of laboratory tests was conducted to determine the measurement system's operational performance characteristics and to demonstrate system capability under simulated operating gas turbine environmental conditions. Operational and environmental performance test data are presented.

  16. Nucleotide-mediated airway clearance.

    PubMed

    Schmid, Andreas; Clunes, Lucy A; Salathe, Mathias; Verdugo, Pedro; Dietl, Paul; Davis, C William; Tarran, Robert

    2011-01-01

    A thin layer of airway surface liquid (ASL) lines the entire surface of the lung and is the first point of contact between the lung and the environment. Surfactants contained within this layer are secreted in the alveolar region and are required to maintain a low surface tension and to prevent alveolar collapse. Mucins are secreted into the ASL throughout the respiratory tract and serve to intercept inhaled pathogens, allergens and toxins. Their removal by mucociliary clearance (MCC) is facilitated by cilia beating and hydration of the ASL by active ion transport. Throughout the lung, secretion, ion transport and cilia beating are under purinergic control. Pulmonary epithelia release ATP into the ASL which acts in an autocrine fashion on P2Y(2) (ATP) receptors. The enzymatic network describes in Chap. 2 then mounts a secondary wave of signaling by surface conversion of ATP into adenosine (ADO), which induces A(2B) (ADO) receptor-mediated responses. This chapter offers a comprehensive description of MCC and the extensive ramifications of the purinergic signaling network on pulmonary surfaces. PMID:21560046

  17. Plasma Creatinine Clearance in the Dog

    ERIC Educational Resources Information Center

    Frazier, Loy W.

    1977-01-01

    Lists materials and methods for an experiment that demonstrates the concept of glomerular filtration rate (GFR) using anesthesized dogs. In the dog, GFR is equivalent to the renal plasma clearance of exogenous creatinine. (CS)

  18. Shear joint capability versus bolt clearance

    NASA Technical Reports Server (NTRS)

    Lee, H. M.

    1992-01-01

    The results of a conservative analysis approach into the determination of shear joint strength capability for typical space-flight hardware as a function of the bolt-hole clearance specified in the design are presented. These joints are comprised of high-strength steel fasteners and abutments constructed of aluminum alloys familiar to the aerospace industry. A general analytical expression was first arrived at which relates bolt-hole clearance to the bolt shear load required to place all joint fasteners into a shear transferring position. Extension of this work allowed the analytical development of joint load capability as a function of the number of fasteners, shear strength of the bolt, bolt-hole clearance, and the desired factor of safety. Analysis results clearly indicate that a typical space-flight hardware joint can withstand significant loading when less than ideal bolt hole clearances are used in the design.

  19. Shear-Joint Capability Versus Bolt Clearance

    NASA Technical Reports Server (NTRS)

    Lee, H. M.

    1994-01-01

    NASA Technical Memorandum presents theoretical study of relationships between load-bearing capabilities of shear joints that comprise plates clamped together by multiple bolts and clearances between bolts and boltholes in those joints.

  20. Voltage-clearance recommendations for printed boards

    SciTech Connect

    Jennings, C W; Cave, G; Evans, A; Harrington, D J; Kirchenbaum, J; Martz, R E; Mierendorf, R C; Smith, G A

    1980-01-01

    Present and future trends in printed board designs point to higher circuit densities with narrower lines and closer spacings. Some designers are now laying out boards with 0.13 mm lines and spacings. The reduction of nominal spacing between conductive elements has raised questions concerning the adequacy of present voltage-clearance recommendations. The present recommendations are considered too conservative in that they are weighted with large safety factors, especially for small clearances, and are frequently disregarded by many designers. Published voltage breakdown measurements made on printed boards with comb patterns with their enhanced conductor test lengths show breakdowns occurring at much higher voltages than those specified for the clearances in existing documents. A Task Group was set up to review published breakdown measurements and to make any additional measurements necessary to provide voltage-clearance recommendations. These recommendations are reported.

  1. Compressor airfoil tip clearance optimization system

    SciTech Connect

    Little, David A.; Pu, Zhengxiang

    2015-08-18

    A compressor airfoil tip clearance optimization system for reducing a gap between a tip of a compressor airfoil and a radially adjacent component of a turbine engine is disclosed. The turbine engine may include ID and OD flowpath boundaries configured to minimize compressor airfoil tip clearances during turbine engine operation in cooperation with one or more clearance reduction systems that are configured to move the rotor assembly axially to reduce tip clearance. The configurations of the ID and OD flowpath boundaries enhance the effectiveness of the axial movement of the rotor assembly, which includes movement of the ID flowpath boundary. During operation of the turbine engine, the rotor assembly may be moved axially to increase the efficiency of the turbine engine.

  2. Year in review 2014: airway clearance.

    PubMed

    Strickland, Shawna L

    2015-04-01

    The respiratory therapist has had integrated adjuncts to improve mucus clearance for decades. However, there is a lack of literature describing the impact of these interventions on specific patient populations, resulting in an inability to make recommendations about the use of devices and techniques. The purpose of this article is to review recent literature regarding airway clearance therapies in a manner that is most likely to have interest to the readers of Respiratory Care. PMID:25784773

  3. Controls Considerations for Turbine Active Clearance Control

    NASA Technical Reports Server (NTRS)

    Melcher, Kevin J.

    2004-01-01

    This presentation discusses active control of turbine tip clearance from a control systems perspective. It is a subset of charts that were presented at the 2003 meeting of the International Society of Air Breathing Engines which was held August 31 through September 5 in Cleveland, Ohio. The associated reference paper is cited at the end of the presentation. The presentation describes active tip clearance control research being conducted by NASA to improve turbine engine systems. The target application for this effort is commercial aircraft engines. However, it is believed that the technologies developed as part of this research will benefit a broad spectrum of current and future turbomachinery. The first part of the presentation discusses the concept of tip clearance, problems associated with it, and the benefits of controlling it. It lays out a framework for implementing tip clearance controls that enables the implementation to progress from purely analytical to hardware-in-the-loop to fully experimental. And it briefly discusses how the technologies developed will be married to the previously described ACC Test Rig for hardware-in-the-loop demonstrations. The final portion of the presentation, describes one of the key technologies in some detail by presenting equations and results for a functional dynamic model of the tip clearance phenomena. As shown, the model exhibits many of the clearance dynamics found in commercial gas turbine engines. However, initial attempts to validate the model identified limitations that are being addressed to make the model more realistic.

  4. ADAPTIVE CLEARANCE CONTROL SYSTEMS FOR TURBINE ENGINES

    NASA Technical Reports Server (NTRS)

    Blackwell, Keith M.

    2004-01-01

    The Controls and Dynamics Technology Branch at NASA Glenn Research Center primarily deals in developing controls, dynamic models, and health management technologies for air and space propulsion systems. During the summer of 2004 I was granted the privilege of working alongside professionals who were developing an active clearance control system for commercial jet engines. Clearance, the gap between the turbine blade tip and the encompassing shroud, increases as a result of wear mechanisms and rubbing of the turbine blades on shroud. Increases in clearance cause larger specific fuel consumption (SFC) and loss of efficient air flow. This occurs because, as clearances increase, the engine must run hotter and bum more fuel to achieve the same thrust. In order to maintain efficiency, reduce fuel bum, and reduce exhaust gas temperature (EGT), the clearance must be accurately controlled to gap sizes no greater than a few hundredths of an inch. To address this problem, NASA Glenn researchers have developed a basic control system with actuators and sensors on each section of the shroud. Instead of having a large uniform metal casing, there would be sections of the shroud with individual sensors attached internally that would move slightly to reform and maintain clearance. The proposed method would ultimately save the airline industry millions of dollars.

  5. Extinction during reconsolidation of threat memory diminishes prefrontal cortex involvement

    PubMed Central

    Schiller, Daniela; Kanen, Jonathan W.; LeDoux, Joseph E.; Monfils, Marie-H.; Phelps, Elizabeth A.

    2013-01-01

    Controlling learned defensive responses through extinction does not alter the threat memory itself, but rather regulates its expression via inhibitory influence of the prefrontal cortex (PFC) over amygdala. Individual differences in amygdala–PFC circuitry function have been linked to trait anxiety and posttraumatic stress disorder. This finding suggests that exposure-based techniques may actually be least effective in those who suffer from anxiety disorders. A theoretical advantage of techniques influencing reconsolidation of threat memories is that the threat representation is altered, potentially diminishing reliance on this PFC circuitry, resulting in a more persistent reduction of defensive reactions. We hypothesized that timing extinction to coincide with threat memory reconsolidation would prevent the return of defensive reactions and diminish PFC involvement. Two conditioned stimuli (CS) were paired with shock and the third was not. A day later, one stimulus (reminded CS+) but not the other (nonreminded CS+) was presented 10 min before extinction to reactivate the threat memory, followed by extinction training for all CSs. The recovery of the threat memory was tested 24 h later. Extinction of the nonreminded CS+ (i.e., standard extinction) engaged the PFC, as previously shown, but extinction of the reminded CS+ (i.e., extinction during reconsolidation) did not. Moreover, only the nonreminded CS+ memory recovered on day 3. These results suggest that extinction during reconsolidation prevents the return of defensive reactions and diminishes PFC involvement. Reducing the necessity of the PFC–amygdala circuitry to control defensive reactions may help overcome a primary obstacle in the long-term efficacy of current treatments for anxiety disorders. PMID:24277809

  6. 48 CFR 801.602-76 - Business clearance review.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Business clearance review... Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is a... obtain a business clearance review prior to award of any contract, task or delivery order, or...

  7. 48 CFR 801.602-76 - Business clearance review.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Business clearance review... Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is a... obtain a business clearance review prior to award of any contract, task or delivery order, or...

  8. 48 CFR 801.602-76 - Business clearance review.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Business clearance review... Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is a... obtain a business clearance review prior to award of any contract, task or delivery order, or...

  9. 19 CFR 4.61 - Requirements for clearance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Requirements for clearance. 4.61 Section 4.61 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.61 Requirements for clearance. (a) Application for clearance. A...

  10. 48 CFR 945.603-70 - Plant clearance function.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Plant clearance function... Plant clearance function. If the plant clearance function has not been formally delegated to another Federal agency, the contracting officer shall assume all responsibilities of the plant clearance...

  11. 48 CFR 945.603-70 - Plant clearance function.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Plant clearance function... Plant clearance function. If the plant clearance function has not been formally delegated to another Federal agency, the contracting officer shall assume all responsibilities of the plant clearance...

  12. 48 CFR 801.602-76 - Business clearance review.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Business clearance review... Authority, and Responsibilities 801.602-76 Business clearance review. (a) A business clearance review is a... obtain a business clearance review prior to award of any contract, task or delivery order, or...

  13. Diminished KCC2 confounds synapse specificity of LTP during senescence.

    PubMed

    Ferando, Isabella; Faas, Guido C; Mody, Istvan

    2016-09-01

    The synapse specificity of long-term potentiation (LTP) ensures that no interference arises from inputs irrelevant to the memory to be encoded. In hippocampi of aged (21-28 months) mice, LTP was relayed to unstimulated synapses, blemishing its synapse specificity. Diminished levels of the K(+)/Cl(-) cotransporter KCC2 and a depolarizing GABAA receptor-mediated synaptic component following LTP were the most likely causes for the spreading of potentiation, unveiling mechanisms hindering information storage in the aged brain and identifying KCC2 as a potential target for intervention. PMID:27500406

  14. Dehydroepiandrosterone (DHEA) supplementation in diminished ovarian reserve (DOR)

    PubMed Central

    2011-01-01

    Background With infertility populations in the developed world rapidly aging, treatment of diminished ovarian reserve (DOR) assumes increasing clinical importance. Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances with DOR, and is now utilized by approximately one third of all IVF centers world-wide. Increasing DHEA utilization and publication of a first prospectively randomized trial now warrants a systematic review. Methods PubMed, Cochrane and Ovid Medline were searched between 1995 and 2010 under the following strategy: [ and diminished ovarian reserve or ovarian function >]. Bibliographies of relevant publications were further explored for additional relevant citations. Since only one randomized study has been published, publications, independent of evidence levels and quality assessment, were reviewed. Results Current best available evidence suggests that DHEA improves ovarian function, increases pregnancy chances and, by reducing aneuploidy, lowers miscarriage rates. DHEA over time also appears to objectively improve ovarian reserve. Recent animal data support androgens in promoting preantral follicle growth and reduction in follicle atresia. Discussion Improvement of oocyte/embryo quality with DHEA supplementation potentially suggests a new concept of ovarian aging, where ovarian environments, but not oocytes themselves, age. DHEA may, thus, represent a first agent beneficially affecting aging ovarian environments. Others can be expected to follow. PMID:21586137

  15. Targeting heparanase overcomes chemoresistance and diminishes relapse in myeloma.

    PubMed

    Ramani, Vishnu C; Zhan, Fenghuang; He, Jianbo; Barbieri, Paola; Noseda, Alessandro; Tricot, Guido; Sanderson, Ralph D

    2016-01-12

    In most myeloma patients, even after several rounds of intensive therapy, drug resistant tumor cells survive and proliferate aggressively leading to relapse. In the present study, gene expression profiling of tumor cells isolated from myeloma patients after sequential rounds of chemotherapy, revealed for the first time that heparanase, a potent promoter of myeloma growth and progression, was elevated in myeloma cells that survived therapy. Based on this clinical data, we hypothesized that heparanase was involved in myeloma resistance to drug therapy. In several survival and viability assays, elevated heparanase expression promoted resistance of myeloma tumor cells to chemotherapy. Mechanistically, this enhanced survival was due to heparanase-mediated ERK signaling. Importantly, use of the heparanase inhibitor Roneparstat in combination with chemotherapy clearly diminished the growth of disseminated myeloma tumors in vivo. Moreover, use of Roneparstat either during or after chemotherapy diminished regrowth of myeloma tumors in vivo following therapy. These results provide compelling evidence that heparanase is a promising, novel target for overcoming myeloma resistance to therapy and that targeting heparanase has the potential to prevent relapse in myeloma and possibly other cancers. PMID:26624982

  16. Diminished appetitive startle modulation following targeted inhibition of prefrontal cortex

    PubMed Central

    Hurlemann, René; Arndt, Stephan; Schlaepfer, Thomas E.; Reul, Juergen; Maier, Wolfgang; Scheele, Dirk

    2015-01-01

    From an evolutionary perspective the startle eye-blink response forms an integral part of the human avoidance behavioral repertoire and is typically diminished by pleasant emotional states. In major depressive disorder (MDD) appetitive motivation is impaired, evident in a reduced interference of positive emotion with the startle response. Given the pivotal role of frontostriatal neurocircuitry in orchestrating appetitive motivation, we hypothesized that inhibitory transcranial magnetic stimulation (TMS) would reduce appetitive neuromodulation in a manner similar to MDD. Based on a pre-TMS functional MRI (fMRI) experiment we selected the left dorsolateral and dorsomedial prefrontal cortices as target regions for subsequent sham-controlled inhibitory theta-burst TMS (TBS) in 40 healthy male volunteers. Consistent with our hypothesis, between-group comparisons revealed a TBS-induced inhibition of appetitive neuromodulation, manifest in a diminished startle response suppression by hedonic stimuli. Collectively, our results suggest that functional integrity of left dorsolateral and dorsomedial prefrontal cortex is critical for mediating a pleasure-induced down-regulation of avoidance responses which may protect the brain from a depressogenic preponderance of defensive stress. PMID:25752944

  17. Diminished appetitive startle modulation following targeted inhibition of prefrontal cortex.

    PubMed

    Hurlemann, René; Arndt, Stephan; Schlaepfer, Thomas E; Reul, Juergen; Maier, Wolfgang; Scheele, Dirk

    2015-01-01

    From an evolutionary perspective the startle eye-blink response forms an integral part of the human avoidance behavioral repertoire and is typically diminished by pleasant emotional states. In major depressive disorder (MDD) appetitive motivation is impaired, evident in a reduced interference of positive emotion with the startle response. Given the pivotal role of frontostriatal neurocircuitry in orchestrating appetitive motivation, we hypothesized that inhibitory transcranial magnetic stimulation (TMS) would reduce appetitive neuromodulation in a manner similar to MDD. Based on a pre-TMS functional MRI (fMRI) experiment we selected the left dorsolateral and dorsomedial prefrontal cortices as target regions for subsequent sham-controlled inhibitory theta-burst TMS (TBS) in 40 healthy male volunteers. Consistent with our hypothesis, between-group comparisons revealed a TBS-induced inhibition of appetitive neuromodulation, manifest in a diminished startle response suppression by hedonic stimuli. Collectively, our results suggest that functional integrity of left dorsolateral and dorsomedial prefrontal cortex is critical for mediating a pleasure-induced down-regulation of avoidance responses which may protect the brain from a depressogenic preponderance of defensive stress. PMID:25752944

  18. Bacterial Keratitis

    MedlinePlus

    ... very quickly, and if left untreated, can cause blindness. The bacteria usually responsible for this type of ... to intense ultraviolet radiation exposure, e.g. snow blindness or welder's arc eye). Next Bacterial Keratitis Symptoms ...

  19. Lipopolysaccharide increases cell surface P-glycoprotein that exhibits diminished activity in intestinal epithelial cells.

    PubMed

    Mishra, Jayshree; Zhang, Qiuye; Rosson, Jessica L; Moran, John; Dopp, John M; Neudeck, Brien L

    2008-10-01

    Increasingly, it is recognized that commensal microflora regulate epithelial cell processes through the dynamic interaction of pathogen-associated molecular patterns and host pattern recognition receptors such as Toll-like receptor 4 (TLR4). We therefore investigated the effects of bacterial lipopolysaccharide (LPS) on intestinal P-glycoprotein (P-gp) expression and function. Human SW480 (P-gp+/TLR4+) and Caco-2 (P-gp+/TLR4-) cells were treated with medium control or LPS (100 ng/ml) for 24 h prior to study. P-gp function was assessed by measuring the intracellular concentration of rhodamine 123 (Rh123). To confirm P-gp-specific effects, breast cancer resistance protein (BCRP/ABCG2) and multidrug resistance-associated protein 2 (MRP-2/ABCC2) were also analyzed. Treatment of SW480 cells with LPS led to diminished P-gp activity, which could be prevented with polymyxin B (control: 207+/-16 versus LPS: 402+/-22 versus LPS+polymyxin B: 238+/-26 pmoles Rh123/mg protein, p<0.05 control versus LPS). These effects could be blocked by using polymyxin B and were not seen in the P-gp+/TLR4--Caco-2 cell line (control: 771+/-28 versus LPS: 775+/-59 pmoles Rh123/mg protein). Total cellular levels of P-gp did not change in LPS-treated SW480 cells; however, a significant increase in cell surface P-gp was detected. No change in activity, total protein, or apically located MRP-2 was detected following LPS treatment. Sequence analysis confirmed wild-type status of SW480 cells. These data suggest that activation of TLR4 in intestinal epithelial cells leads to an increase in plasma membrane P-gp that demonstrates a diminished capacity to transport substrate. PMID:18687802

  20. Diminished dose minimally invasive radioguided parathyroidectomy: a case for radioguidance.

    PubMed

    You, Christopher J; Zapas, John L

    2007-07-01

    Minimally invasive radioguided parathyroidectomy (MIRP) has been established as an alternative to bilateral neck exploration (BNE) for primary hyperparathyroidism. We investigate whether a diminished dose of technetium-99m sestamibi gives similar results to the standard dose. One hundred one patients were offered MIRP or diminished-dose MIRP (ddMIRP). Patients received intravenous Tc-99m sestamibi at a dose of either 25 mCi 1.5 hours or 5 mCi 1 hour preoperatively. The procedure was terminated when the 20 per cent rule was satisfied. All tissue was confirmed to be parathyroid tissue by frozen section analysis. In addition, intraoperative parathyroid hormone levels were measured in a majority of patients. Patients who failed IOM underwent BNE. Frozen section analysis and intraoperative parathyroid hormone monitoring were also performed in the BNEs. Postoperatively, serum calcium levels were measured at 1 week and 6 months. Fifteen per cent of patients were male and 85 per cent were female. The median age was 63 years (range, 25-89 years). The first 58 patients had the standard dose of 25 mCi, whereas 43 patients had ddMIRP. Six patients (10%) failed intraoperative mapping in the MIRP group and were found to have single-gland disease. Five patients (12%) failed intraoperative mapping in the ddMIRP group. However, two patients were identified to have multigland disease making the true failure rate of intraoperative mapping 7 per cent (three patients). Median operative times for MIRP, ddMIRP, and BNE were 40 minutes, 46 minutes, and 105 minutes, respectively. The 20 per cent rule was satisfied in 96 per cent of patients undergoing MIRP and 98 per cent of patients undergoing ddMIRP. Frozen section analysis and intraoperative parathyroid hormone monitoring did not result in a change in management. Median follow up was 193 days and serum calcium levels at 6 months were normal. Diminished-dose MIRP is a feasible alternative to standard-dose MIRP without compromising

  1. Clinical application of plasma clearance of iohexol on feline patients.

    PubMed

    Miyamoto, K

    2001-09-01

    Glomerular filtration rate (GFR) was estimated by plasma clearance of iohexol (PCio) in 52 conscious cats presented for a variety of reasons to Angel Animal Hospital over a 2-year period. Cats were divided into four groups according to their clinical conditions and reasons for measuring PCio. The median PCio (ml/min/kg) was 3.68 in normal cats (NM), 2.39 in cats with suspected renal disease (SP), 1.35 in cats referred to confirm renal dysfunction (RD), and 0.84 in cats with apparent clinical signs of renal failure (RF). There was a significant difference between the results for each group. The respective medians of blood urea nitrogen (BUN) and plasma creatinine concentration (Pcr) (mg/dl) were 15 and 1.40 in NM cats, 21 and 1.71 in SP cats, 30 and 2.20 in RD cats, and 48 and 3.30 in RF cats. The reference values of BUN and Pcr were 21 +/- 7 mg/dl and 1.5 +/- 0.4 mg/dl (mean +/- SD). Diminished renal function could not be detected in SP cats by either BUN or Pcr, while a marked decrease of GFR was demonstrated before BUN and Pcr increased, indicating the insensitivity of BUN and Pcr in detecting renal dysfunction in cats. PCio can be performed non-invasively in conscious cats, which improves the veterinarian's ability to detect early stages of chronic renal disease. PMID:11876631

  2. Assessment of Total Variation Diminishing schemes in combustion instability problems

    NASA Technical Reports Server (NTRS)

    Wang, Z. J.; Yang, H. Q.; Przekwas, A. J.

    1993-01-01

    Numerical simulations of acoustic waves in a shear layer and in an idealized combustion chamber using high resolution Total Variation Diminishing (TVD) schemes has been carried out to study the effects of inherent scheme dissipation and dispersion errors of this class of problems. The numerical results are compared against available exact solutions to quantify these errors. Several popular TVD limiters widely used in the Computational Fluid Dynamics (CFD) community have been assessed. Osher-Chakravarthy limiters are modified so that they can be used in explicit schemes. Among all the limiters investigated, Osher-Chakravarthy third-order limiter is identified as having performed the best. It is also found that all TVD schemes have exceptionally small dispersive errors.

  3. Social Presence Diminishes Contagious Yawning in the Laboratory

    PubMed Central

    Gallup, Andrew; Church, Allyson M.; Miller, Heather; Risko, Evan F.; Kingstone, Alan

    2016-01-01

    Contagious yawning may be a useful measure of social psychological functioning, and thus it is important to evaluate the variables influencing its expression in laboratory settings. Previous research has documented that humans yawn less frequently in crowded environments and when under direct observation, but the impact of social presence on contagious yawning remains unknown. Here we present the first study to systematically alter the degree of social presence experienced by participants in the laboratory to determine its effect on contagious yawning frequency. Our results demonstrate that both implied and actual social presence significantly diminish yawn contagion in comparison to a control condition, indicating a key social component to contagious yawning. These findings provide a framework for pursuing additional research investigating the social factors influencing contagious yawning, while also offering applications for measuring this response in laboratory settings. PMID:27112374

  4. Necessary Clearance to Prevent Side Flashes

    NASA Astrophysics Data System (ADS)

    Shindo, Takatoshi; Asakawa, Akira; Honda, Hideki; Sakae, Maki; Tanaka, Shuusaku

    Side flashes often occur when lightning strikes a tree and cause injury or death of human beings staying nearby the tree. Necessary clearance to prevent the side flash has been said to be 2 m, but the physical meaning of the value is unclear. In this paper, we have proposed a model of side flashes based on the physics of discharges and necessary clearance has been calculated. Furthermore, we have carried out model experiments of the side flash using real trees of a heights of 3.5 m and a naturally growing tree of a height of more than 10 m. The results of the model experiments have verified the proposed theory and it is concluded that clearance of more than 3 m from a tree is necessary to prevent side flashes from the tree.

  5. Glycerol clearance in alcoholic liver disease.

    PubMed Central

    Johnston, D G; Alberti, K G; Wright, R; Blain, P G

    1982-01-01

    Glycerol clearance was studied by a primed dose-constant infusion technique in 14 patients with alcoholic liver disease and six normal control subjects. Fasting blood glycerol concentrations were raised in the alcoholic subjects (0.09 +/- 0.01 vs 0.06 +/- 0.01 mumol/l, p less than 0.05) and glycerol clearance was impaired (24.5 +/- 1.9 vs 37.5 +/- 3.2 ml/kg/min, p less than 0.005). Endogenous production rate of glycerol and distribution space at steady state were similar in alcoholic and control subjects. The metabolic clearance rate of glycerol correlated negatively with basal glycerol concentrations. Thus tissue uptake of glycerol is impaired in liver disease. As glycerol is metabolised primarily in the liver by conversion to glucose, these data suggest a defect of gluconeogenesis in alcoholic liver disease. PMID:7076002

  6. Pharmacologic agents for mucus clearance in bronchiectasis.

    PubMed

    Nair, Girish B; Ilowite, Jonathan S

    2012-06-01

    There are no approved pharmacologic agents to enhance mucus clearance in non-cystic fibrosis (CF) bronchiectasis. Evidence supports the use of hyperosmolar agents in CF, and studies with inhaled mannitol and hypertonic saline are ongoing in bronchiectasis. N-acetylcysteine may act more as an antioxidant than a mucolytic in other lung diseases. Dornase α is beneficial to patients with CF, but is not useful in patients with non-CF bronchiectasis. Mucokinetic agents such as β-agonists have the potential to improve mucociliary clearance in normals and many disease states, but have not been adequately studied in patients with bronchiectasis. PMID:22640851

  7. Prediction of hepatic microsomal intrinsic clearance and human clearance values for drugs.

    PubMed

    Nikolic, Katarina; Agababa, Danica

    2009-10-01

    Twenty-nine drugs of different structures were used in theoretical QSAR analysis of human hepatic microsomal intrinsic clearance (in vitro T(1/2) and in vitro CL'(int)) and whole body clearance (CL(blood)). The examined compounds demonstrated a wide range of scaled intrinsic clearance values. Constitutional, geometrical, physico-chemical and electronic descriptors were computed for the examined structures by use of the Marvin Sketch 5.1.3_2, the Chem3D Ultra 7.0.0 and the Dragon 5.4 program. Partial least squares regression (PLSR), has been applied for selection of the most relevant molecular descriptors and development of quantitative structure-activity relationship (QSAR) model for human hepatic microsomal intrinsic clearance (in vitro T(1/2)). Optimal QSAR models with nine and ten variables, R(2)>0.808 and cross-validation parameter q(pre)(2)>0.623, were selected and compared. Since the microsomal in vitro T(1/2) data can be used for calculation of in vitro CL'(int) and in vivo CL(blood), the developed QSAR model will enable one to analyze the kinetics of cytochrome P450-mediated reactions in term of intrinsic clearance and whole body clearance. A comparison is made between predictions produced from the QSAR analysis and experimental data, and there appears to be generally satisfactory correlations with the literature values for intrinsic clearance data. PMID:19713138

  8. Enhanced Clearance of Pseudomonas aeruginosa by Peroxisome Proliferator-Activated Receptor Gamma.

    PubMed

    Bedi, Brahmchetna; Yuan, Zhihong; Joo, Myungsoo; Zughaier, Susu M; Goldberg, Joanna B; Arbiser, Jack L; Hart, C Michael; Sadikot, Ruxana T

    2016-07-01

    The pathogenic profile of Pseudomonas aeruginosa is related to its ability to secrete a variety of virulence factors. Quorum sensing (QS) is a mechanism wherein small diffusible molecules, specifically acyl-homoserine lactones, are produced by P. aeruginosa to promote virulence. We show here that macrophage clearance of P. aeruginosa (PAO1) is enhanced by activation of the nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPARγ). Macrophages treated with a PPARγ agonist (pioglitazone) showed enhanced phagocytosis and bacterial killing of PAO1. It is known that PAO1 QS molecules are inactivated by PON-2. QS molecules are also known to inhibit activation of PPARγ by competitively binding PPARγ receptors. In accord with this observation, we found that infection of macrophages with PAO1 inhibited expression of PPARγ and PON-2. Mechanistically, we show that PPARγ induces macrophage paraoxonase 2 (PON-2), an enzyme that degrades QS molecules produced by P. aeruginosa Gene silencing studies confirmed that enhanced clearance of PAO1 in macrophages by PPARγ is PON-2 dependent. Further, we show that PPARγ agonists also enhance clearance of P. aeruginosa from lungs of mice infected with PAO1. Together, these data demonstrate that P. aeruginosa impairs the ability of host cells to mount an immune response by inhibiting PPARγ through secretion of QS molecules. These studies define a novel mechanism by which PPARγ contributes to the host immunoprotective effects during bacterial infection and suggest a role for PPARγ immunotherapy for P. aeruginosa infections. PMID:27091928

  9. Bacterial Immunity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of bacterial agents reside in and around the environment that can cause illness and death in a poultry flock. Many cause disseminated disease while others exert more local effects such as the respiratory or gastrointestinal tract. The host, for our current purposes the laying hen, has de...

  10. 32 CFR 154.16 - Security clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be processed for a security clearance in accordance with 32 CFR part 353 and the provisions of this... shall be accomplished in accordance with 32 CFR part 159. The investigative requirement shall be the... security personnel who have no access to classified information. (11) To drivers, chauffeurs and...

  11. 32 CFR 154.16 - Security clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be processed for a security clearance in accordance with 32 CFR part 353 and the provisions of this... shall be accomplished in accordance with 32 CFR part 159. The investigative requirement shall be the... security personnel who have no access to classified information. (11) To drivers, chauffeurs and...

  12. Mediators and mucociliary clearance in asthma.

    PubMed

    Pavia, D; Lopez-Vidriero, M T; Clarke, S W

    1987-01-01

    Lung mucociliary clearance is significantly reduced in asthmatic patients compared to healthy controls even during clinical remission. Further retardation in mucous clearance occurs during sleep per se and this may be a contributing factor to nocturnal asthma. Chemical mediators of anaphylaxis appear to have various and, sometimes opposing effects on the two essential components for mucociliary clearance, namely cilia and mucus. Some mediators such as leukotrienes C4 and D4 are potent secretagogues and histamine increases the water flux into the lumen of the airways from the mucosa. Slow-reacting substance of anaphylaxis (SRS-A) reduces mucus transport whereas histamine enhances it. Ciliostimulation has been reported following allergen challenge and this contrasts with the cilioinhibitory effect of asthmatics' sputa. It appears however, that the net effect of the various chemicals of anaphylaxis is one of impairment of mucus clearance. Some pharmacological agents, used for the relief of bronchospasm and control of asthma, also stimulate mucociliary transport, a desirable additional effect. PMID:3311245

  13. 28 CFR 524.74 - Activities clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Activities clearance. 524.74 Section 524.74 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INMATE ADMISSION, CLASSIFICATION, AND TRANSFER CLASSIFICATION OF INMATES Central Inmate Monitoring (CIM) System § 524.74...

  14. 30 CFR 57.11008 - Restricted clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Restricted clearance. 57.11008 Section 57.11008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Travelways and Escapeways Travelways-Surface and Underground §...

  15. 30 CFR 57.11010 - Stairstep clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Stairstep clearance. 57.11010 Section 57.11010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Travelways and Escapeways Travelways-Surface and Underground...

  16. 15 CFR 752.15 - Export clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... accordance with requirements of the Foreign Trade Statistics Regulations (15 CFR part 30) and § 758.1 of the... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Export clearance. 752.15 Section 752... OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS...

  17. 49 CFR 192.325 - Underground clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Underground clearance. 192.325 Section 192.325 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM...

  18. Mechanisms of viral clearance and persistence.

    PubMed

    Borrow, P

    1997-01-01

    Using examples predominantly drawn from study of the lymphocytic choriomeningitis virus (LCMV) model system, this review describes the mechanisms involved in control of virus infections by the cell-mediated immune response, and some of the different strategies viruses have evolved to evade such immune clearance so that they can persist in their hosts. The important role played by the CD8+ cytotoxic lymphocyte (CTL) response in clearance of many systemic virus infections is discussed; and it is emphasized that although CD8+ CTL are classically thought of as lymphocytes which mediate lysis of virus-infected target cells, the principal mechanism by which CD8+ T cells effect clearance of persistent and many acute virus infections via production of antiviral cytokines such as tumour necrosis factor-alpha and interferon-gamma, not via destruction of virus-producing cells. To avoid immune-mediated clearance, viruses frequently use a combination of several different strategies. These can be grouped into mechanisms for avoiding recognition by the immune response (such as establishing latent infections, replicating in immune-privileged sites, down-regulating the expression of immune recognition signals on the surface of infected cells, or undergoing antigenic variation); and mechanisms for suppressing the immune response. The latter include generalized immune suppression mechanisms, and strategies for more precisely disabling the specific immune response such as inducing tolerance or exhaustion of virus-specific CTL. The value of understanding both immune clearance mechanisms and viral evasion strategies in the rational design of immune-based therapies to combat persistent virus infections is discussed. PMID:9429206

  19. Overeducation and depressive symptoms: diminishing mental health returns to education.

    PubMed

    Bracke, Piet; Pattyn, Elise; von dem Knesebeck, Olaf

    2013-11-01

    In general, well-educated people enjoy better mental health than those with less education. As a result, some wonder whether there are limits to the mental health benefits of education. Inspired by the literature on the expansion of tertiary education, this article explores marginal mental health returns to education and studies the mental health status of overeducated people. To enhance the validity of the findings we use two indicators of educational attainment - years of education and ISCED97 categories - and two objective indicators of overeducation (the realised matches method and the job analyst method) in a sample of the working population of 25 European countries (unweighted sample N = 19,089). Depression is measured using an eight-item version of the CES-D scale. We find diminishing mental health returns to education. In addition, overeducated people report more depression symptoms. Both findings hold irrespective of the indicators used. The results must be interpreted in the light of the enduring expansion of education, as our findings show that the discussion of the relevance of the human capital perspective, and the diploma disease view on the relationship between education and modern society, is not obsolete. PMID:23909439

  20. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins

    PubMed Central

    Yao, Chunxiang; Behring, Jessica B.; Shao, Di; Sverdlov, Aaron L.; Whelan, Stephen A.; Elezaby, Aly; Yin, Xiaoyan; Siwik, Deborah A.; Seta, Francesca; Costello, Catherine E.; Cohen, Richard A.; Matsui, Reiko; Colucci, Wilson S.; McComb, Mark E.; Bachschmid, Markus M.

    2015-01-01

    Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2), react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat), an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a ‘Tandem Mass Tag’ (TMT) labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg) mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation. PMID:26642319

  1. 75 FR 70341 - Agency Information Collection Activities: Emergency Clearance Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY ADMINISTRATION Agency Information Collection Activities: Emergency Clearance Request The Social Security..._Submission@omb.eop.gov . (SSA), Social Security Administration, DCBFM, Attn: Reports Clearance Officer,...

  2. 19 CFR 122.26 - Entry and clearance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... AIR COMMERCE REGULATIONS Private Aircraft § 122.26 Entry and clearance. Private aircraft, as defined... information as set forth in § 122.22(c), and grants electronic clearance via electronic mail or telephone....

  3. 14 CFR 375.24 - Entry and clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Rules Generally Applicable § 375.24 Entry and clearance. All U.S. entry and clearance requirements for aircraft, passengers, crews,...

  4. 14 CFR 375.24 - Entry and clearance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Rules Generally Applicable § 375.24 Entry and clearance. All U.S. entry and clearance requirements for aircraft, passengers, crews,...

  5. 14 CFR 375.24 - Entry and clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Rules Generally Applicable § 375.24 Entry and clearance. All U.S. entry and clearance requirements for aircraft, passengers, crews,...

  6. 14 CFR 375.24 - Entry and clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Rules Generally Applicable § 375.24 Entry and clearance. All U.S. entry and clearance requirements for aircraft, passengers, crews,...

  7. 10 CFR 95.17 - Processing facility clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... NUCLEAR REGULATORY COMMISSION (CONTINUED) FACILITY SECURITY CLEARANCE AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.17 Processing facility clearance. (a... pertinent laws, and the nature of international security and information exchange agreements. The...

  8. 77 FR 44641 - Critical Infrastructure Private Sector Clearance Program Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-30

    ... SECURITY Critical Infrastructure Private Sector Clearance Program Request AGENCY: National Protection and... Programs Directorate (NPPD), Office of Infrastructure Protection (IP) will submit the following Information... Infrastructure Private Sector Clearance Program (PSCP). DHS previously published this ICR in the Federal...

  9. 77 FR 21989 - Critical Infrastructure Private Sector Clearance Program Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ... SECURITY Critical Infrastructure Private Sector Clearance Program Request AGENCY: National Protection and... Programs Directorate (NPPD), Office of Infrastructure Protection (IP) will submit the following Information... information provided. SUPPLEMENTARY INFORMATION: The Critical Infrastructure Private Sector Clearance...

  10. WWW-based data entry for document clearance requests

    SciTech Connect

    Stasiak, D.M.

    1997-10-08

    All documents created at Argonne must be cleared before being published. The clearance process is coordinated by the Publications and Record Services. The Electronic Document Review and Clearance System (EDRC) consists of a Web-based system for submission of clearance requests, an electronic staging area for document awaiting review, and Web-based review and clearance of documents. This report covers the document clearing process, the EDRC system, expected benefits/costs, and a demonstration.

  11. Inflammation and clearance of Chlamydia trachomatis in enteric and nonenteric mucosae.

    PubMed

    Igietseme, J U; Portis, J L; Perry, L L

    2001-03-01

    Immunization(s) fostering the induction of genital mucosa-targeted immune effectors is the goal of vaccines against sexually transmitted diseases. However, it is uncertain whether vaccine administration should be based on the current assumptions about the common mucosal immune system. We investigated the relationship between mucosal sites of infection, infection-induced inflammation, and immune-mediated bacterial clearance in mice using the epitheliotropic pathogen Chlamydia trachomatis. Chlamydial infection of the conjunctival, pulmonary, or genital mucosae stimulated significant changes in tissue architecture with dramatic up-regulation of the vascular addressin, VCAM, a vigorous mixed-cell inflammatory response with an influx of alpha4beta1+ T cells, and clearance of bacteria within 30 days. Conversely, intestinal mucosa infection was physiologically inapparent, with no change in expression of the local MAdCAM addressin, no VCAM induction, no histologically detectable inflammation, and no tissue pathology. Microbial clearance was complete within 60 days in the small intestine but bacterial titers remained at high levels for at least 8 months in the large intestine. These findings are compatible with the notion that VCAM plays a functional role in recruiting cells to inflammatory foci, and its absence from the intestinal mucosa contributes to immunologic homeostasis at that site. Also, expression of type 1 T cell-mediated immunity to intracellular Chlamydia may exhibit tissue-specific variation, with the rate and possibly the mechanism(s) of clearance differing between enteric and nonenteric mucosae. The implications of these data for the common mucosal immune system and the delivery of vaccines against mucosal pathogens are discussed. PMID:11179361

  12. Neonatal Pulmonary Macrophage Depletion Coupled to Defective Mucus Clearance Increases Susceptibility to Pneumonia and Alters Pulmonary Immune Responses.

    PubMed

    Saini, Yogesh; Wilkinson, Kristen J; Terrell, Kristy A; Burns, Kimberlie A; Livraghi-Butrico, Alessandra; Doerschuk, Claire M; O'Neal, Wanda K; Boucher, Richard C

    2016-02-01

    Resident immune cells (e.g., macrophages [MΦs]) and airway mucus clearance both contribute to a healthy lung environment. To investigate interactions between pulmonary MΦ function and defective mucus clearance, a genetic model of lysozyme M (LysM) promoter-mediated MΦ depletion was generated, characterized, and crossed with the sodium channel β subunit transgenic (Scnn1b-Tg) mouse model of defective mucus clearance. Diphtheria toxin A-mediated depletion of LysM(+) pulmonary MΦs in wild-type mice with normal mucus clearance resulted in lethal pneumonia in 24% of neonates. The pneumonias were dominated by Pasteurella pneumotropica and accompanied by emaciation, neutrophilic inflammation, and elevated Th1 cytokines. The incidence of emaciation and pneumonia reached 51% when LysM(+) MΦ depletion was superimposed on the airway mucus clearance defect of Scnn1b-Tg mice. In LysM(+) MΦ-depleted Scnn1b-Tg mice, pneumonias were associated with a broader spectrum of bacterial species and a significant reduction in airway mucus plugging. Bacterial burden (CFUs) was comparable between Scnn1b-Tg and nonpneumonic LysM(+) MΦ-depleted Scnn1b-Tg mice. However, the nonpneumonic LysM(+) MΦ-depleted Scnn1b-Tg mice exhibited increased airway inflammation, the presence of neutrophilic infiltration, and increased levels of inflammatory cytokines in bronchoalveolar lavage fluid compared with Scnn1b-Tg mice. Collectively, these data identify key MΦ-mucus clearance interactions with respect to both infectious and inflammatory components of muco-obstructive lung disease. PMID:26121027

  13. Citrobacter rodentium mouse model of bacterial infection.

    PubMed

    Crepin, Valerie F; Collins, James W; Habibzay, Maryam; Frankel, Gad

    2016-10-01

    Infection of mice with Citrobacter rodentium is a robust model to study bacterial pathogenesis, mucosal immunology, the health benefits of probiotics and the role of the microbiota during infection. C. rodentium was first isolated by Barthold from an outbreak of mouse diarrhea in Yale University in 1972 and was 'rediscovered' by Falkow and Schauer in 1993. Since then the use of the model has proliferated, and it is now the gold standard for studying virulence of the closely related human pathogens enteropathogenic and enterohemorrhagic Escherichia coli (EPEC and EHEC, respectively). Here we provide a detailed protocol for various applications of the model, including bacterial growth, site-directed mutagenesis, mouse inoculation (from cultured cells and after cohabitation), monitoring of bacterial colonization, tissue extraction and analysis, immune responses, probiotic treatment and microbiota analysis. The main protocol, from mouse infection to clearance and analysis of tissues and host responses, takes ∼5 weeks to complete. PMID:27606775

  14. 30 CFR 56.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance on adjacent tracks. 56.9103 Section..., Hauling, and Dumping Traffic Safety § 56.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  15. 30 CFR 57.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clearance on adjacent tracks. 57.9103 Section..., Hauling, and Dumping Traffic Safety § 57.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  16. 30 CFR 56.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clearance on adjacent tracks. 56.9103 Section..., Hauling, and Dumping Traffic Safety § 56.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  17. 30 CFR 57.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance on adjacent tracks. 57.9103 Section..., Hauling, and Dumping Traffic Safety § 57.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  18. 23 CFR Appendix B to Part 1327 - OMB Clearance

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false OMB Clearance B Appendix B to Part 1327 Highways NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PROCEDURES FOR PARTICIPATING..., App. B Appendix B to Part 1327—OMB Clearance The OMB clearance number of this regulation is OMB...

  19. 61 FR 11709 - Real Estate Title Clearance and Loan Closing

    Federal Register 2010, 2011, 2012, 2013, 2014

    1996-03-22

    ... 0575-AB52 Real Estate Title Clearance and Loan Closing AGENCIES: Rural Housing Service, Rural Business... ``agency,'' amend the Real Estate Title Clearance and Loan Closing regulation. This action makes loan.... The proposed rule discussed the need to make real estate title clearance and loan closing...

  20. 59 FR- Real Estate Title Clearance and Loan Closing

    Federal Register 2010, 2011, 2012, 2013, 2014

    1994-05-11

    .... SUMMARY: The Farmers Home Administration (FmHA) proposes to amend its Real Estate Title Clearance and Loan... changes affect FmHA processing, real estate title clearance, and loan closing. Paperwork Reduction Act The... EO. Discussion FmHA recognizes the need to make Real Estate Title Clearance and Loan...

  1. 14 CFR 1260.63 - Customs clearance and visas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas...

  2. 14 CFR 1260.63 - Customs clearance and visas.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas...

  3. 14 CFR 1260.63 - Customs clearance and visas.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas...

  4. 14 CFR § 1260.63 - Customs clearance and visas.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Customs clearance and visas. § 1260.63 Section § 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance...

  5. 14 CFR 1260.63 - Customs clearance and visas.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Customs clearance and visas. 1260.63 Section 1260.63 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS General Special Conditions § 1260.63 Customs clearance and visas. Customs Clearance and Visas...

  6. Wear analysis of revolute joints with clearance in multibody systems

    NASA Astrophysics Data System (ADS)

    Bai, ZhengFeng; Zhao, Yang; Wang, XingGui

    2013-08-01

    In this work, the prediction of wear for revolute joint with clearance in multibody systems is investigated using a computational methodology. The contact model in clearance joint is established using a new hybrid nonlinear contact force model and the friction effect is considered by using a modified Coulomb friction model. The dynamics model of multibody system with clearance is established using dynamic segmentation modeling method and the computational process for wear analysis of clearance joint in multibody systems is presented. The main computational process for wear analysis of clearance joint includes two steps, which are dynamics analysis and wear analysis. The dynamics simulation of multibody system with revolute clearance joint is carried out and the contact forces are drawn and used to calculate the wear amount of revolute clearance joint based on the Archard's wear model. Finally, a four-bar multibody mechanical system with revolute clearance joint is used as numerical example application to perform the simulation and show the dynamics responses and wear characteristics of multibody systems with revolute clearance joint. The main results of this work indicate that the contact between the joint elements is wider and more frequent in some specific regions and the wear phenomenon is not regular around the joint surface, which causes the clearance size increase non-regularly after clearance joint wear. This work presents an effective method to predict wear of revolute joint with clearance in multibody systems.

  7. 10 CFR 95.17 - Processing facility clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Processing facility clearance. 95.17 Section 95.17 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) FACILITY SECURITY CLEARANCE AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.17 Processing facility clearance. (a) Following the receipt of an acceptable...

  8. 48 CFR 245.602-70 - Plant clearance procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Plant clearance procedures... Disposal 245.602-70 Plant clearance procedures. Follow the procedures at PGI 245.602-70 for establishing and processing a plant clearance case....

  9. 48 CFR 945.670-1 - Plant clearance function.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... contracting officer shall assume all responsibilities of the plant clearance officer identified in 48 CFR 45... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Plant clearance function... MANAGEMENT GOVERNMENT PROPERTY Reporting, Reutilization, and Disposal 945.670-1 Plant clearance function....

  10. 48 CFR 945.670-1 - Plant clearance function.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... contracting officer shall assume all responsibilities of the plant clearance officer identified in 48 CFR 45... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Plant clearance function... MANAGEMENT GOVERNMENT PROPERTY Reporting, Reutilization, and Disposal 945.670-1 Plant clearance function....

  11. 48 CFR 245.602-70 - Plant clearance procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Plant clearance procedures... Disposal 245.602-70 Plant clearance procedures. Follow the procedures at PGI 245.602-70 for establishing and processing a plant clearance case....

  12. 48 CFR 245.602-70 - Plant clearance procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Plant clearance procedures... Disposal 245.602-70 Plant clearance procedures. Follow the procedures at PGI 245.602-70 for establishing and processing a plant clearance case....

  13. 48 CFR 245.602-70 - Plant clearance procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Plant clearance procedures... Disposal 245.602-70 Plant clearance procedures. Follow the procedures at PGI 245.602-70 for establishing and processing a plant clearance case....

  14. 33 CFR 157.455 - Minimum under-keel clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Minimum under-keel clearance. 157... § 157.455 Minimum under-keel clearance. (a) The owner or operator of a tankship, that is not fitted with... written under-keel clearance guidance that includes— (1) Factors to consider when calculating the...

  15. 33 CFR 157.455 - Minimum under-keel clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Minimum under-keel clearance. 157... § 157.455 Minimum under-keel clearance. (a) The owner or operator of a tankship, that is not fitted with... written under-keel clearance guidance that includes— (1) Factors to consider when calculating the...

  16. 24 CFR 3285.305 - Clearance under homes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Clearance under homes. 3285.305... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.305 Clearance under homes. A minimum clearance of 12 inches must be maintained between the lowest member of the main...

  17. 24 CFR 3285.305 - Clearance under homes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Clearance under homes. 3285.305... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.305 Clearance under homes. A minimum clearance of 12 inches must be maintained between the lowest member of the main...

  18. 46 CFR 56.75-10 - Joint clearance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Joint clearance. 56.75-10 Section 56.75-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Brazing § 56.75-10 Joint clearance. (a) The clearance between surfaces to be joined shall be...

  19. 46 CFR 56.75-10 - Joint clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Joint clearance. 56.75-10 Section 56.75-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Brazing § 56.75-10 Joint clearance. (a) The clearance between surfaces to be joined shall be...

  20. 46 CFR 56.75-10 - Joint clearance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Joint clearance. 56.75-10 Section 56.75-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Brazing § 56.75-10 Joint clearance. (a) The clearance between surfaces to be joined shall be...

  1. 46 CFR 56.75-10 - Joint clearance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Joint clearance. 56.75-10 Section 56.75-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Brazing § 56.75-10 Joint clearance. (a) The clearance between surfaces to be joined shall be...

  2. 46 CFR 56.75-10 - Joint clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Joint clearance. 56.75-10 Section 56.75-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Brazing § 56.75-10 Joint clearance. (a) The clearance between surfaces to be joined shall be...

  3. 30 CFR 56.9330 - Clearance for surface equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clearance for surface equipment. 56.9330... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Loading... Dumping Sites § 56.9330 Clearance for surface equipment. Continuous clearance of at least 30 inches...

  4. 10 CFR 95.17 - Processing facility clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... clearances (PCLs); and (4) Appointing a U.S. citizen employee as the facility security officer. (b) An... NUCLEAR REGULATORY COMMISSION (CONTINUED) FACILITY SECURITY CLEARANCE AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.17 Processing facility clearance....

  5. 24 CFR 3285.305 - Clearance under homes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Clearance under homes. 3285.305... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.305 Clearance under homes. A minimum clearance of 12 inches must be maintained between the lowest member of the main...

  6. 24 CFR 3285.305 - Clearance under homes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Clearance under homes. 3285.305... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.305 Clearance under homes. A minimum clearance of 12 inches must be maintained between the lowest member of the main...

  7. 24 CFR 3285.305 - Clearance under homes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Clearance under homes. 3285.305... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.305 Clearance under homes. A minimum clearance of 12 inches must be maintained between the lowest member of the main...

  8. 10 CFR 95.23 - Termination of facility clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) FACILITY SECURITY CLEARANCE AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.23 Termination of facility clearance. (a... determination that continued facility clearance is not in the interest of national security. (b) When...

  9. 14 CFR 27.661 - Rotor blade clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  10. 14 CFR 29.661 - Rotor blade clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  11. 14 CFR 27.661 - Rotor blade clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  12. 14 CFR 29.661 - Rotor blade clearance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  13. 14 CFR 29.661 - Rotor blade clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  14. 14 CFR 29.661 - Rotor blade clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  15. 14 CFR 27.661 - Rotor blade clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  16. 14 CFR 27.661 - Rotor blade clearance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  17. 14 CFR 27.661 - Rotor blade clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor blade clearance. 27.661 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Rotors § 27.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  18. 14 CFR 29.661 - Rotor blade clearance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor blade clearance. 29.661 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Rotors § 29.661 Rotor blade clearance. There must be enough clearance between the rotor blades and other parts of the structure...

  19. Evaluation of an Active Clearance Control System Concept

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Lattime, Scott B.; Taylor, Shawn; DeCastro, Jonathan A.; Oswald, Jay; Melcher, Kevin J.

    2005-01-01

    Reducing blade tip clearances through active tip clearance control in the high pressure turbine can lead to significant reductions in emissions and specific fuel consumption as well as dramatic improvements in operating efficiency and increased service life. Current engines employ scheduled cooling of the outer case flanges to reduce high pressure turbine tip clearances during cruise conditions. These systems have relatively slow response and do not use clearance measurement, thereby forcing cold build clearances to set the minimum clearances at extreme operating conditions (e.g., takeoff, reburst) and not allowing cruise clearances to be minimized due to the possibility of throttle transients (e.g., step change in altitude). In an effort to improve upon current thermal methods, a first generation mechanically-actuated active clearance control (ACC) system has been designed and fabricated. The system utilizes independent actuators, a segmented shroud structure, and clearance measurement feedback to provide fast and precise active clearance control throughout engine operation. Ambient temperature performance tests of this first generation ACC system assessed individual seal component leakage rates and both static and dynamic overall system leakage rates. The ability of the nine electric stepper motors to control the position of the seal carriers in both open- and closed-loop control modes for single and multiple cycles was investigated. The ability of the system to follow simulated engine clearance transients in closed-loop mode showed the system was able to track clearances to within a tight tolerance ( 0.001 in. error).

  20. Evaluation of an Active Clearance Control System Concept

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Lattime, Scott B.; DeCastro, Jonathan A.; Oswald, Jay; Melcher, Kevin J.

    2005-01-01

    Reducing blade tip clearances through active tip clearance control in the high pressure turbine can lead to significant reductions in emissions and specific fuel consumption as well as dramatic improvements in operating efficiency and increased service life. Current engines employ scheduled cooling of the outer case flanges to reduce high pressure turbine tip clearances during cruise conditions. These systems have relatively slow response and do not use clearance measurement, thereby forcing cold build clearances to set the minimum clearances at extreme operating conditions (e.g., takeoff, reburst) and not allowing cruise clearances to be minimized due to the possibility of throttle transients (e.g., step change in altitude). In an effort to improve upon current thermal methods, a first generation mechanically-actuated active clearance control (ACC) system has been designed and fabricated. The system utilizes independent actuators, a segmented shroud structure, and clearance measurement feedback to provide fast and precise active clearance control throughout engine operation. Ambient temperature performance tests of this first generation ACC system assessed individual seal component leakage rates and both static and dynamic overall system leakage rates. The ability of the nine electric stepper motors to control the position of the seal carriers in both open- and closed-loop control modes for single and multiple cycles was investigated. The ability of the system to follow simulated engine clearance transients in closed-loop mode showed the system was able to track clearances to within a tight tolerance (0.001 in. error).

  1. Iron diminishes the in vitro biological effect of vanadium.

    PubMed

    Ghio, Andrew J; Stonehuerner, Jacqueline; Soukup, Joleen M; Dailey, Lisa A; Kesic, Matthew J; Cohen, Mitchell D

    2015-06-01

    Mechanistic pathways underlying inflammatory injury following exposures to vanadium-containing compounds are not defined. We tested the postulate that the in vitro biological effect of vanadium results from its impact on iron homeostasis. Human bronchial epithelial (HBE) cells exposed to vanadyl sulfate (VOSO4) showed a time- and dose-dependent increase in vanadium relative to PBS. HBE cells exposed to VOSO4 and then exposed to ferric ammonium citrate (FAC) significantly increased intracellular iron import supporting an interaction between the two metals. Following exposure to VOSO4, there was an increase (336±73%) in RNA for divalent metal transporter 1 (DMT1), a major iron importer. With inclusion of VOSO4 in the incubation, vanadium could be measured in the nuclear and mitochondrial fractions and the supernatant. Non-heme iron in the nuclear and mitochondrial fractions were decreased immediately following VOSO4 exposure while there was an increased concentration of non-heme iron in the supernatant. Provision of excess iron inhibited changes in the concentration of this metal provoked by VOSO4 exposures. Using Amplex Red, VOSO4 was shown to significantly increase oxidant generation by HBE cells in a time- and dose-dependent manner. HBE cells pre-treated with FAC and then exposed to VOSO4 demonstrated a decreased generation of oxidants. Similarly, activation of the transcription factor NF-ĸB promoter and release of interleukin-6 and -8 were increased following VOSO4 exposure and these effects were diminished by pre-treatment with FAC. We conclude that an initiating event in biological effect after exposure to vanadyl sulfate is a loss of requisite cell iron. PMID:25843360

  2. STARVATION INDUCED PROXIMAL GUT MUCOSAL ATROPHY DIMINISHED WITH AGING

    PubMed Central

    Song, Juquan; Wolf, Steven E.; Wu, Xiao-Wu; Finnerty, Celeste C.; Gauglitz, Gerd G.; Herndon, David N.; Jeschke, Marc G.

    2013-01-01

    Background Starvation induces small bowel atrophy with increased intestinal epithelial apoptosis and decreased proliferation. Here, we examined these parameters after starvation in aged animals. Methods Sixty-four 6 week-old and 26 month-old C57BL/6 mice were randomly assigned to either an ad libitum fed or fasted group. The small bowel was harvested at 12, 48, and 72 hours following starvation. Proximal gut mucosal height was measured and epithelial cells counted. Apoptosis was identified by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Proliferation was determined by immunohistochemical staining for proliferating cell nuclear antigen (PCNA). Comparison of fed vs. fasted and adult vs. old groups was done by one-way ANOVA with Tukey’s test and unpaired t-test. Significance was accepted at p<0.05. Results Aged mice had higher proximal gut weights, mucosal heights and cell numbers at baseline compared with the adult group (p<0.05). The rate of apoptosis was lower in the aged (p<0.05) while proliferation was not different between groups before starvation. After starvation, proximal gut wet weight decreased only in adult mice (p<0.05); Gut mucosal height and mucosal cell number decreased greater in adult than in aged mice (p<0.05). This was related to decreased proliferation only in the adult group (p<0.05). The fold of epithelial apoptosis increased was higher in the aged group than in the adult after starvation (p<0.05). Conclusions Gut mucosal kinetics change with age had lower rates of apoptosis and greater mucosal mass; the character of starvation-induced atrophy is diminished with aging. PMID:19126762

  3. Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

    PubMed

    Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

    2010-07-01

    Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia. PMID:20558844

  4. Human's choices in situations of time-based diminishing returns.

    PubMed Central

    Hackenberg, T D; Axtell, S A

    1993-01-01

    Three experiments examined adult humans' choices in situations with contrasting short-term and long-term consequences. Subjects were given repeated choices between two time-based schedules of points exchangeable for money: a fixed schedule and a progressive schedule that began at 0 s and increased by 5 s with each point delivered by that schedule. Under "reset" conditions, choosing the fixed schedule not only produced a point but it also reset the requirements of the progressive schedule to 0 s. In the first two experiments, reset conditions alternated with "no-reset" conditions, in which progressive-schedule requirements were independent of fixed-schedule choices. Experiment 1 entailed choices between a progressive-interval schedule and a fixed-interval schedule, the duration of which varied across conditions. Switching from the progressive- to the fixed-interval schedule was systematically related to fixed-interval size in 4 of 8 subjects, and in all subjects occurred consistently sooner in the progressive-schedule sequence under reset than under no-reset procedures. The latter result was replicated in a second experiment, in which choices between progressive- and fixed-interval schedules were compared with choices between progressive- and fixed-time schedules. In Experiment 3, switching patterns under reset conditions were unrelated to variations in intertrial interval. In none of the experiments did orderly choice patterns depend on verbal descriptions of the contingencies or on schedule-controlled response patterns in the presence of the chosen schedules. The overall pattern of results indicates control of choices by temporarily remote consequences, and is consistent with versions of optimality theory that address performance in situations of diminishing returns. PMID:8315364

  5. [Bacterial vaginosis].

    PubMed

    Romero Herrero, Daniel; Andreu Domingo, Antonia

    2016-07-01

    Bacterial vaginosis (BV) is the main cause of vaginal dysbacteriosis in the women during the reproductive age. It is an entity in which many studies have focused for years and which is still open for discussion topics. This is due to the diversity of microorganisms that cause it and therefore, its difficult treatment. Bacterial vaginosis is probably the result of vaginal colonization by complex bacterial communities, many of them non-cultivable and with interdependent metabolism where anaerobic populations most likely play an important role in its pathogenesis. The main symptoms are an increase of vaginal discharge and the unpleasant smell of it. It can lead to serious consequences for women, such as an increased risk of contracting sexually transmitted infections including human immunodeficiency virus and upper genital tract and pregnancy complications. Gram stain is the gold standard for microbiological diagnosis of BV, but can also be diagnosed using the Amsel clinical criteria. It should not be considered a sexually transmitted disease but it is highly related to sex. Recurrence is the main problem of medical treatment. Apart from BV, there are other dysbacteriosis less characterized like aerobic vaginitis of which further studies are coming slowly but are achieving more attention and consensus among specialists. PMID:27474242

  6. Pathogenesis and pathophysiology of bacterial meningitis.

    PubMed Central

    Tunkel, A R; Scheld, W M

    1993-01-01

    Bacterial meningitis remains a disease with associated unacceptable morbidity and mortality rates despite the availability of effective bactericidal antimicrobial therapy. Through the use of experimental animal models of infection, a great deal of information has been gleaned concerning the pathogenic and pathophysiologic mechanisms operable in bacterial meningitis. Most cases of bacterial meningitis begin with host acquisition of a new organism by nasopharyngeal colonization followed by systemic invasion and development of a high-grade bacteremia. Bacterial encapsulation contributes to this bacteremia by inhibiting neutrophil phagocytosis and resisting classic complement-mediated bactericidal activity. Central nervous system invasion then occurs, although the exact site of bacterial traversal into the central nervous system is unknown. By production and/or release of virulence factors into and stimulation of formation of inflammatory cytokines within the central nervous system, meningeal pathogens increase permeability of the blood-brain barrier, thus allowing protein and neutrophils to move into the subarachnoid space. There is then an intense subarachnoid space inflammatory response, which leads to many of the pathophysiologic consequences of bacterial meningitis, including cerebral edema and increased intracranial pressure. Attenuation of this inflammatory response with adjunctive dexamethasone therapy is associated with reduced concentrations of tumor necrosis factor in the cerebrospinal fluid, with diminished cerebrospinal fluid leukocytosis, and perhaps with improvement of morbidity, as demonstrated in recent clinical trials. Further information on the pathogenesis and pathophysiology of bacterial meningitis should lead to the development of more innovative treatment and/or preventive strategies for this disorder. Images PMID:8472245

  7. Gas turbine engine active clearance control

    NASA Technical Reports Server (NTRS)

    Deveau, Paul J. (Inventor); Greenberg, Paul B. (Inventor); Paolillo, Roger E. (Inventor)

    1985-01-01

    Method for controlling the clearance between rotating and stationary components of a gas turbine engine are disclosed. Techniques for achieving close correspondence between the radial position of rotor blade tips and the circumscribing outer air seals are disclosed. In one embodiment turbine case temperature modifying air is provided in flow rate, pressure and temperature varied as a function of engine operating condition. The modifying air is scheduled from a modulating and mixing valve supplied with dual source compressor air. One source supplies relatively low pressure, low temperature air and the other source supplies relatively high pressure, high temperature air. After the air has been used for the active clearance control (cooling the high pressure turbine case) it is then used for cooling the structure that supports the outer air seal and other high pressure turbine component parts.

  8. Autophagy promotes DNA-protein crosslink clearance.

    PubMed

    Mu, Haibo; Liu, Qianjin; Niu, Hong; Wang, Dongdong; Tang, Jiangjiang; Duan, Jinyou

    2016-02-01

    Toxic DNA-protein crosslinks (DPCs) can result from exposure to radiation or chemotherapeutic agents. DPCs can also accumulate during aging or stress. However, the cellular mechanisms underlying clearance of DPCs remain largely unknown. Here, we have identified an important role of autophagy in the processing of DPCs induced by three representative agents: formaldehyde, a chemical used widely in industry; UV light; and camptothecin, a cytotoxic anticancer drug. Autophagy inhibitors, 3-methyladenine (3-MA) or chloroquine (CQ), promoted the accumulation of DPCs in damaged cells and injured organs. siRNA-mediated silencing of Atg5 or Atg7, two essential components for the formation of the autophagosome, gave similar results. In contrast, the autophagy inducer rapamycin (RAP) attenuated DPCs in vitro and in vivo. Our findings reveal the importance of autophagy in controlling the level of DPCs, and may open up a new avenue for understanding the formation and clearance of this detrimental DNA adduct. PMID:26921017

  9. High-Clearance Six-Wheel Suspension

    NASA Technical Reports Server (NTRS)

    Bickler, Donald B.

    1992-01-01

    Multilevered suspension system gives body of vehicle high clearance and allows wheels to be steered independently. Suspension linkages above wheels enable body to skim over obstacles as high as wheel. Levers and independently steered wheels enable vehicle to climb steps 1 1/2 wheel diameters high and cross gaps 1 3/4 wide. Adaptable to off-the-road recreational vehicles, military scout vehicles, and robotic emergency vehicles.

  10. Instrument for Measuring Engine Clearance Volumes

    NASA Technical Reports Server (NTRS)

    Sparrow, S W

    1920-01-01

    With the advent of the V type engine, a new method to measure the clearance volume in cylinders was needed. It was suggested that this measurement could be made by a process which consisted essentially of simultaneously changing both a known and unknown volume of gas by a known amount and then calculating the magnitude of the unknown from the resulting difference in pressure between the two. An instrument based on this design is described.

  11. Deposition and clearance of inhaled particles.

    PubMed Central

    Stuart, B O

    1976-01-01

    Theoretical models of respiratory tract deposition of inhaled particles are compared to experimental studies of deposition patterns in humans and animals, as determined principally by particle size, density, respiratory rate and flow parameters. Various models of inhaled particle deposition make use of convenient approximations of the respiratory tract to predict tractional deposition according to fundamental physical processes of impaction, sedimentation, and diffusion. These theoretical models for both total deposition and regional (nasopharyngeal, tracheobronchial, and pulmonary) deposition are compared with experimental studies of inhaled dusts in humans or experimental animals that have been performed in many laboratories over several decades. Reasonable correlation has been obtained between theoretical and experimental studies, but the behavior of very fine (less than 0.01 mum) particles requires further refinement.Properties of particle shape, charge, and hygroscopicity as well as the degree of respiratory tract pathology also influence deposition patterns and further experimental work is urgently needed in these areas. The influence upon deposition patterns of dynamic alterations in inspiratory flow profiles caused by a variety of breathing patterns also requires further study, and the use of such techniques with selected inhaled particle size holds promise in possible diagnostic aid in diagnosis of normal versus disease conditions. Mechanisms of conducting airway and alveolar clearance processes involving mucociliary clearance, dissolution, transport to systemic circulation, and translocation via regional lymphatic clearance are discussed. The roles of the pulmonary macrophage in airway and alveolar clearance are described, and the applicability of recent solubility models for translocation or deposited materials to liver, skeleton, or other systemic organs is discussed. PMID:797567

  12. Impact of glycation on antibody clearance.

    PubMed

    Yang, Jane; Primack, Ronya; Frohn, Mike; Wang, Wei; Luan, Peng; Retter, Marc W; Flynn, Gregory C

    2015-01-01

    Glycation of therapeutic proteins occurs during mammalian cell culture expression and upon administration to patients. Since the chemical attachment of mannose or other sugars via a chemical linker has been shown to increase a protein's clearance rate in mice through the mannose receptor, we explored the effect of mannose glycation on the clearance of an IgG in mice. An IgG decorated with high levels of mannose (~18 mol/mol protein) through glycation did not clear faster in mice than the underivatized protein, whereas the same IgG decorated with mannose attached in a way to maintain the normal glycosidic bond (2-imino-2-methoxyethyl-1-thiomannoside, or IMT-mannose) at similar derivatization levels cleared significantly faster. Surface plasmon resonance studies revealed that the IgG derivatized with IMT-mannose bound tightly to the mannose receptor (KD = 20 nM) but the IgG glycated with mannose did not bind. These results indicate that glycation, even at unnaturally elevated levels, does not appear to be a clearance concern for therapeutic proteins. PMID:25413724

  13. Diminished Mercury Emission From Water Surfaces by Duckweed (Lemna minor)

    NASA Astrophysics Data System (ADS)

    Wollenberg, J. L.; Peters, S. C.

    2007-12-01

    Aquatic plants of the family Lemnaceae (generally referred to as duckweeds) are a widely distributed type of floating vegetation in freshwater systems. Under suitable conditions, duckweeds form a dense vegetative mat on the water surface, which reduces light penetration into the water column and decreases the amount of exposed water surface. These two factors would be expected to reduce mercury emission by limiting a) direct photoreduction of Hg(II), b) indirect reduction via coupled DOC photooxidation-Hg(II) reduction, and c) gas diffusion across the water-air interface. Conversely, previous studies have demonstrated transpiration of Hg(0) by plants, so it is therefore possible that the floating vegetative mat would enhance emission via transpiration of mercury vapor. The purpose of this experiment was to determine whether duckweed limits mercury flux to the atmosphere by shading and the formation of a physical barrier to diffusion, or whether it enhances emission from aquatic systems via transpiration of Hg(0). Deionized water was amended with mercury to achieve a final concentration of approximately 35 ng/L and allowed to equilibrate prior to the experiment. Experiments were conducted in rectangular polystyrene flux chambers with measured UV-B transmittance greater than 60% (spectral cutoff approximately 290 nm). Light was able to penetrate the flux chamber from the sides as well as the top throughout the experiment, limiting the effect of shading by duckweed on the water surface. Flux chambers contained 8L of water with varying percent duckweed cover, and perforated plastic sheeting was used as an abiotic control. Exposures were conducted outside on days with little to no cloud cover. Real time mercury flux was measured using atomic absorption (Mercury Instruments UT-3000). Total solar and ultraviolet radiation, as well as a suite of meteorological parameters, were also measured. Results indicate that duckweed diminishes mercury emission from the water surface

  14. Diminished Baroreflex Control of Forearm Vascular Resistance Following Training

    NASA Technical Reports Server (NTRS)

    Mack, G. W.; Thompson, C. A.; Doerr, D. F.; Nadel, E. R.; Convertino, V. A.

    1991-01-01

    The stimulus-response characteristics of cardiopulmonary baroreflex control of forearm vascular resistance (FVR units in mm Hg x min x I00 ml/ml) were studied in 14 volunteers before and after 10 wk of endurance training. We assessed the relationship betaleen reflex stimulus (changes in central venous pressure, CVP) and response (FVR) during unloading of cardiopulmonary baroreceptors with lower body negative pressure (LBNP, 0 to - 2O mm Hg). Changes in CVP during LBNP were estimated from pressure changes in a large peripheral vein in the dependent arm of the subject in the right lateral decubitus position. Maximal oxygen uptake (VO(sub 2max)) and total blood volume increased with endurance training from 37.8 +/- 1.4 ml/min x kg and 63.6 +/- 2.1 ml/kg to 45.3 +/- 1.4 ml/ min x kg and 69.3 +/- 2.8 ml/kg respectively (P less than 0.05). Reflex forearm vasoconstriction occurred in response to a reduction in estimated CVP, and the absolute change in FVR per unit of CVP was reduced from -5.96 +/- 0.79 to -4.06 +/- 0.52 units x mm/ Hg (P less than 0.05) following exercise training but was unchanged from -6.10 to 0.57 to -6.22 +/- 0.94 units x mm/ Hg for the time control group (N = 7). Resting values for FVR were similar before and after exercise training; however, resting estimated CVP was elevated from 9.5 +/- 0.5 mm x Hg before training to 11.3 +/- 0.6 mm x Hg after training. The reduction in sensitivity of the cardiopulmonary baroreflex control of FVR was linearly related to the increase in blood volume (r = 0.65, P less than 0.05). suggesting that diminished cardiopulmonary baroreflex control of FVR in physically fit individuals is related, in part, to a training-induced blood volume expansion.

  15. How to diminish calcium loss and muscle atrophy in space

    NASA Astrophysics Data System (ADS)

    Gorgolewski, S.

    perfect relaxation when asleep or awake. We have to check in space if we can thus diminish the use of medicaments or even eliminate them. Slow Yoga exercises decrease also the amount on food required because life is not so energy demanding in space as it is here under the earth's gravitation. We can stay lean and healthy with such static yet most effective physical exercises. In addition it gives us for free a vegetarian life style, just another benefit so useful in space travel.

  16. Similarity analysis of compressor tip clearance flow structure

    NASA Technical Reports Server (NTRS)

    Chen, G. T.; Greitzer, E. M.; Tan, C. S.; Marble, F. E.

    1991-01-01

    A new approach is presented for analyzing compressor tip clearance flow. The basic idea is that the clearance velocity field can be (approximately) decomposed into independent throughflow and crossflow, since chordwise pressure gradients are much smaller than normal pressure gradients in the clearance region. As in the slender body approximation in external aerodynamics, this description implies that the three-dimensional steady clearance flow can be viewed as a two-dimensional, unsteady flow. Using this approach, a similarity scaling for the crossflow in the clearance region is developed and a generalized description of the clearance vortex is derived. Calculations based on the similarity scaling agree well with a wide range of experimental data in regard to flow features such as crossflow velocity field, static pressure field, and tip clearance vortex trajectory.

  17. Analysis and experimental study of the spherical joint clearance

    NASA Astrophysics Data System (ADS)

    Zhao, Peng; Hu, Penghao; Bao, Xinxin; Li, Shuaipeng

    2013-10-01

    The spherical joint clearance is a key error factor, which influenced and restricted the application of parallel mechanism in high precision field. This paper discusses the regularity of the spherical joint clearance in the parallel mechanism and its influence on the accuracy of the parallel mechanism in both theoretical and experimental aspects. A spherical joint clearance measuring instrument is introduced and used to measure the joint clearance. And the relationship between the clearance and its work pose is revealed. Based on the theoretical and experimental analysis, it is concluded that the clearance of the spherical joint is near-linear proportional to the applied load as well as the clearances in different poses obey the Rayleigh distribution approximately under the same load.

  18. Deposition, retention, and clearance of inhaled particles.

    PubMed Central

    Lippmann, M; Yeates, D B; Albert, R E

    1980-01-01

    The relation between the concentrations and characteristics of air contaminants in the work place and the resultant toxic doses and potential hazards after their inhalation depends greatly on their patterns of deposition and the rates and pathways for their clearance from the deposition sites. The distribution of the deposition sites of inhaled particles is strongly dependent on their aerodynamic diameters. For normal man, inhaled non-hygroscopic particles greater than or equal to 2 micrometers that deposit in the conducting airways by impaction are concentrated on to a small fraction of the surface. Cigarette smoking and bronchitis produce a proximal shift in the deposition pattern. The major factor affecting the deposition of smaller particles is their transfer from tidal to reserve air. For particles soluble in respiratory tract fluid, systemic uptake may be relatively complete for all deposition patterns, and there may be local toxic or irritant effects or both. On the other hand, slowly soluble particles depositing in the conducting airways are carried on the surface to the glottis and are swallowed within one day. Mucociliary transport rates are highly variable, both along the ciliated airways of a given individual and between individuals. The changes in clearance rates produced by drugs, cigarette smoke, and other environmental pollutants can greatly increase or decrease these rates. Particles deposited in non-ciliated airways have large surface-to-volume ratios, and clearance by dissolution can occur for materials generally considered insoluble. They may also be cleared as free particles either by passive transport along surface liquids or, after phagocytosis, by transport within alveolar macrophages. If the particles penetrate the epithelium, either bare or within macrophages, they may be sequestered within cells or enter the lymphatic circulation and be carried to pleural, hilar, and more distant lymph nodes. Non-toxic insoluble particles are cleared from

  19. Bacterial Games

    NASA Astrophysics Data System (ADS)

    Frey, Erwin; Reichenbach, Tobias

    Microbial laboratory communities have become model systems for studying the complex interplay between nonlinear dynamics of evolutionary selection forces, stochastic fluctuations arising from the probabilistic nature of interactions, and spatial organization. Major research goals are to identify and understand mechanisms that ensure viability of microbial colonies by allowing for species diversity, cooperative behavior and other kinds of "social" behavior. A synthesis of evolutionary game theory, nonlinear dynamics, and the theory of stochastic processes provides the mathematical tools and conceptual framework for a deeper understanding of these ecological systems. We give an introduction to the modern formulation of these theories and illustrate their effectiveness, focusing on selected examples of microbial systems. Intrinsic fluctuations, stemming from the discreteness of individuals, are ubiquitous, and can have important impact on the stability of ecosystems. In the absence of speciation, extinction of species is unavoidable, may, however, take very long times. We provide a general concept for defining survival and extinction on ecological time scales. Spatial degrees of freedom come with a certain mobility of individuals. When the latter is sufficiently high, bacterial community structures can be understood through mapping individual-based models, in a continuum approach, onto stochastic partial differential equations. These allow progress using methods of nonlinear dynamics such as bifurcation analysis and invariant manifolds. We conclude with a perspective on the current challenges in quantifying bacterial pattern formation, and how this might have an impact on fundamental research in nonequilibrium physics .

  20. Enhanced respiratory clearance of nontypeable Haemophilus influenzae following mucosal immunization with P6 in a rat model.

    PubMed

    Kyd, J M; Dunkley, M L; Cripps, A W

    1995-08-01

    Nontypeable Haemophilus influenzae (NTHi) is a common cause of infection of the respiratory tract in children and adults. The search for an effective vaccine against this pathogen has focused on components of the outer membrane, and peptidoglycan-associated lipoprotein P6 is among the proposed candidates. This study investigated the immunogenicity of P6 in a rat respiratory model. P6 was purified from two strains of NTHi, one capsule-deficient strain and an H. influenzae type b strain, and assessed for clearance of both homologous and heterologous bacterial strains following mucosal immunization. A protective immune response was determined by enhancement of pulmonary clearance of live bacteria and an increased rate of recruitment of phagocytic cells to the lungs. This was most effective when Peyer's patch immunization was accompanied by an intratracheal (IT) boost. However, the rate of bacterial clearance varied between strains, which suggests some differences in anti-P6 immunological defenses recognizing the expression of the highly conserved P6 lipoprotein on the bacterial surface in some strains. P6-specific antibodies in both serum and bronchoalveolar lavage fluid were cross-reactive and did not differ significantly in strain specificity, demonstrating that difference in clearance was unlikely due to differences in P6-specific antibody levels. Serum homologous and heterologous P6-antibody was bactericidal against NTHi even when enhanced clearance had not been observed. Peyer's patch immunization induced P6-specific CD4+ T-helper cell proliferation in lymphocytes isolated from the mesenteric lymph nodes. An IT boost increased the level of P6-specific antibodies in serum and bronchoalveolar lavage fluid, and P6-specific mesenteric node lymphocyte proliferation. Cells from rats immunized with P6 demonstrated proliferation following stimulation with P6 from nonhomologous strains; however, there was some variation in proliferative responses to P6 from different

  1. Testosterone treatment diminishes sickness behavior in male songbirds.

    PubMed

    Ashley, Noah T; Hays, Quentin R; Bentley, George E; Wingfield, John C

    2009-06-01

    Males of many vertebrate species are typically more prone to disease and infection than female conspecifics, and this sexual difference is partially influenced by the immunosuppressive properties of testosterone (T) in males. T-induced immunosuppression has traditionally been viewed as a pleiotropic handicap, rather than an adaptation. Recently, it has been hypothesized that suppression of sickness behavior, or the symptoms of infection, may have adaptive value if sickness interferes with the expression of T-mediated behaviors important for male reproductive success. We conduct a classic hormone replacement experiment to examine if T suppresses sickness behavior in a seasonally-breeding songbird, Gambel's white-crowned sparrow (Zonotrichia leucophrys gambelii). Triggered experimentally by bacterial lipopolysaccharide (LPS), sickness behavior includes decreased activity, anorexia, and weight loss. Gonadectomized (GDX) males that were treated with silastic implants filled with T exhibited suppression of behavioral and physiological responses to LPS compared to GDX and sham-GDX controls given empty implants. Sickness responses of control groups were statistically indistinguishable. T-implanted birds had significantly higher plasma T than control groups and levels were within the range associated with aggressive interactions during male-to-male contests. These findings imply that suppression of sickness behavior could occur when T is elevated to socially-modulated levels. Alternatively, it is possible that this suppressive effect is mediated through a stress-induced mechanism, as corticosterone levels were elevated in T-implanted subjects compared to controls. We propose that males wounded and infected during contests may gain a brief selective advantage by suppressing sickness responses that would otherwise impair competitive performance. The cost of immunosuppression would be manifested in males through an increased susceptibility to disease, which is presumably

  2. Spanish black radish (Raphanus sativus L. Var. niger) diet enhances clearance of DMBA and diminishes toxic effects on bone marrow progenitor cells.

    PubMed

    N'jai, Alhaji U; Kemp, Michael Q; Metzger, Brandon T; Hanlon, Paul R; Robbins, Melissa; Czuyprynski, Charles; Barnes, David M

    2012-01-01

    Vegetables of the Cruciferae family contain high levels of glucosinolates, metabolites of which are believed to enhance detoxification. Spanish black radishes (SBR) contain 4× more glucosinolates than other crucifers. This study examined whether feeding mice a diet containing 20% SBR for 2 wk could enhance metabolism of 7,12-dimethylbenz(a)anthracene (DMBA) and inhibit DMBA-mediated bone marrow toxicity. Expression of Phase I and II detoxification enzymes was significantly greater for mice fed SBR than control diet. Six hours after DMBA administration, the blood levels of DMBA in mice fed the SBR diet were significantly lower than mice fed a control diet. DMBA reduced bone marrow cells in mice fed control diet to a significantly greater extent than mice fed the SBR diet. Colony forming assays demonstrated that mice on the SBR diet had 1) less reduction in lymphoid CFU-preB progenitor cells, 2) greater recovery of CFU-preB progenitor cells at 168 h, and 3) less reduction of CFU-GM progenitor cells at 6 h. Therefore, mice fed a 20% SBR diet for 2 wk had greater expression of detoxification enzymes, faster metabolism of DMBA, and a reduction in DMBA-induced bone marrow toxicity. Overall, these results support the hypothesis that glucosinolates in SBR are protective against acute toxicity. PMID:23061907

  3. Diminished Primary and Secondary Influenza Virus-Specific CD8+ T-Cell Responses in CD4-Depleted Ig−/− Mice

    PubMed Central

    Riberdy, Janice M.; Christensen, Jan P.; Branum, Kristen; Doherty, Peter C.

    2000-01-01

    Optimal expansion of influenza virus nucleoprotein (DbNP366)-specific CD8+ T cells following respiratory challenge of naive Ig−/− μMT mice was found to require CD4+ T-cell help, and this effect was also observed in primed animals. Absence of the CD4+ population was consistently correlated with diminished recruitment of virus-specific CD8+ T cells to the infected lung, delayed virus clearance, and increased morbidity. The splenic CD8+ set generated during the recall response in Ig−/− mice primed at least 6 months previously showed a normal profile of gamma interferon production subsequent to short-term, in vitro stimulation with viral peptide, irrespective of a concurrent CD4+ T-cell response. Both the magnitude and the localization profiles of virus-specific CD8+ T cells, though perhaps not their functional characteristics, are thus modified in mice lacking CD4+ T cells. PMID:11000251

  4. Chronic Bacterial Pathogens: Mechanisms of Persistence

    PubMed Central

    Byndloss, Mariana X.; Tsolis, Renee M

    2015-01-01

    Summary Many bacterial pathogens can cause acute infections that are cleared with onset of adaptive immunity, however a subset of these pathogens can establish persistent, and sometimes lifelong infections. While bacteria causing chronic infections are phylogenetically diverse, they share common features in their interactions with the host that enable a protracted period of colonization. This chapter will compare the persistence strategies of two chronic pathogens from the Proteobacteria, Brucella abortus, and Salmonella enterica serovar Typhi (S. Typhi) to consider how these two pathogens, which are very different at the genomic level, can utilize common strategies to evade immune clearance to cause chronic intracellular infections of the mononuclear phagocyte system. PMID:27227304

  5. Bacterial Hydrodynamics

    NASA Astrophysics Data System (ADS)

    Lauga, Eric

    2016-01-01

    Bacteria predate plants and animals by billions of years. Today, they are the world's smallest cells, yet they represent the bulk of the world's biomass and the main reservoir of nutrients for higher organisms. Most bacteria can move on their own, and the majority of motile bacteria are able to swim in viscous fluids using slender helical appendages called flagella. Low-Reynolds number hydrodynamics is at the heart of the ability of flagella to generate propulsion at the micrometer scale. In fact, fluid dynamic forces impact many aspects of bacteriology, ranging from the ability of cells to reorient and search their surroundings to their interactions within mechanically and chemically complex environments. Using hydrodynamics as an organizing framework, I review the biomechanics of bacterial motility and look ahead to future challenges.

  6. Effects of passive smoking on theophylline clearance.

    PubMed

    Matsunga, S K; Plezia, P M; Karol, M D; Katz, M D; Camilli, A E; Benowitz, N L

    1989-10-01

    Theophylline disposition was examined in seven passive smokers, defined as nonsmokers with long-term exposure to cigarette smoke, and seven age-matched nonsmokers with minimal smoke exposure. Subjects were given an intravenous infusion of aminophylline (6 mg/kg) and blood samples were drawn before and during the 48-hour postinfusion period. Clearance for passive smokers was 6.01 x 10(-2) L/hr.kg and for nonsmokers, clearance was 4.09 x 10(-2) L/hr.kg (p less than 0.025). Terminal elimination half-life for passive smokers was 6.93 hours versus 8.69 hours for nonsmokers (p less than 0.05). The mean residence time for passive smokers was 9.89 hours. For nonsmokers, the mean residence time was 13.11 hours (p less than 0.05). These measurements were statistically different, whereas there was no difference in volume of distribution between the groups, suggesting that passive smokers metabolize theophylline more rapidly than nonsmokers. Plasma and urine cotinine and nicotine concentrations were measured in all subjects. There was a significant difference between the subject groups in plasma (p less than 0.004) and urine (p less than 0.002) cotinine concentrations. Theophylline clearance correlated with both plasma (r = 0.73, p less than 0.01) and urine (r = 0.79, p less than 0.01) cotinine concentrations. Additional studies should be conducted to further define the pharmacokinetic characteristics of passive smokers and to assess the effects of passive smoking on drugs metabolized by the mixed function oxidase system. PMID:2791443

  7. Statistical Tolerance and Clearance Analysis for Assembly

    NASA Technical Reports Server (NTRS)

    Lee, S.; Yi, C.

    1996-01-01

    Tolerance is inevitable because manufacturing exactly equal parts is known to be impossible. Furthermore, the specification of tolerances is an integral part of product design since tolerances directly affect the assemblability, functionality, manufacturability, and cost effectiveness of a product. In this paper, we present statistical tolerance and clearance analysis for the assembly. Our proposed work is expected to make the following contributions: (i) to help the designers to evaluate products for assemblability, (ii) to provide a new perspective to tolerance problems, and (iii) to provide a tolerance analysis tool which can be incorporated into a CAD or solid modeling system.

  8. Increased lethality and defective pulmonary clearance of Streptococcus pneumoniae in microsomal prostaglandin E synthase-1-knockout mice.

    PubMed

    Dolan, Jennifer M; Weinberg, Jason B; O'Brien, Edmund; Abashian, Anya; Procario, Megan C; Aronoff, David M; Crofford, Leslie J; Peters-Golden, Marc; Ward, Lindsay; Mancuso, Peter

    2016-06-01

    The production of prostaglandin E2 (PGE2) increases dramatically during pneumococcal pneumonia, and this lipid mediator impairs alveolar macrophage (AM)-mediated innate immune responses. Microsomal prostaglandin E synthase-1 (mPGES-1) is a key enzyme involved in the synthesis of PGE2, and its expression is enhanced during bacterial infections. Genetic deletion of mPGES-1 in mice results in diminished PGE2 production and elevated levels of other prostaglandins after infection. Since PGE2 plays an important immunoregulatory role during bacterial pneumonia we assessed the impact of mPGES-1 deletion in the host defense against pneumococcal pneumonia in vivo and in AMs in vitro. Wild-type (WT) and mPGES-1 knockout (KO) mice were challenged with Streptococcus pneumoniae via the intratracheal route. Compared with WT animals, we observed reduced survival and increased lung and spleen bacterial burdens in mPGES-1 KO mice 24 and 48 h after S. pneumoniae infection. While we found modest differences between WT and mPGES-1 KO mice in pulmonary cytokines, AMs from mPGES-1 KO mice exhibited defective killing of ingested bacteria in vitro that was associated with diminished inducible nitric oxide synthase expression and reduced nitric oxide (NO) synthesis. Treatment of AMs from mPGES-1 KO mice with an NO donor restored bacterial killing in vitro. These results suggest that mPGES-1 plays a critical role in bacterial pneumonia and that genetic ablation of this enzyme results in diminished pulmonary host defense in vivo and in vitro. These results suggest that specific inhibition of PGE2 synthesis by targeting mPGES-1 may weaken host defense against bacterial infections. PMID:27059285

  9. Study of blade clearance effects on centrifugal pumps

    NASA Technical Reports Server (NTRS)

    Hoshide, R. K.; Nielson, C. E.

    1972-01-01

    A program of analysis, design, fabrication, and testing has been conducted to develop and experimentally verify analytical models to predict the effects of impeller blade clearance on centrifugal pumps. The effect of tip clearance on pump efficiency, and the relationship between the head coefficient and torque loss with tip clearance was established. Analysis were performed to determine the cost variation in design, manufacture, and test that would occur between unshrouded and shrouded impellers. An impeller, representative of typical rocket engine impellers, was modified by removing its front shroud to permit variation of its blade clearances. It was tested in water with special instrumentation to provide measurements of blade surface pressures during operation. Pump performance data were obtained from tests at various impeller tip clearances. Blade pressure data were obtained at the nominal tip clearance. Comparisons of predicted and measured data are given.

  10. Dynamics analysis of space robot manipulator with joint clearance

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Bai, Zheng Feng

    2011-04-01

    A computational methodology for analysis of space robot manipulator systems, considering the effects of the clearances in the joint, is presented. The contact dynamics model in joint clearance is established using the nonlinear equivalent spring-damp model and the friction effect is considered using the Coulomb friction model. The space robot system dynamic equation of manipulator with clearance is established. Then the dynamics simulation is presented and the dynamics characteristics of robot manipulator with clearance are analyzed. This work provides a practical method to analyze the dynamics characteristics of space robot manipulator with joint clearance and improves the engineering application. The computational methodology can predict the effects of clearance on space robot manipulator preferably, which is the basis of space robot manipulator design, precision analysis and ground test.

  11. Single-dose gentamicin clearance is a predictor of creatinine clearance in spinal man.

    PubMed

    Segal, Jack L; Gilman, Thomas A; Thompson, John F

    2010-01-01

    To identify a radionuclide-free, SCI (spinal cord injury) population-specific method for estimating renal function utilizing the total body clearance of gentamicin as a measure of creatinine clearance (CL(cr)) and glomerular filtration rate (GFR). To incorporate SCI population-specific patient variables into a predictive model for estimating CLcr and GFR. A retrolective study of gentamicin clearance as a measure of GFR in patients with SCI. Each patient had received a single, intravenous dose of gentamicin. Simultaneously, a 24-hour creatinine clearance (CL(cr-24)) was obtained. Experimentally measured total body clearance of a single intravenous administration of gentamicin (CL(gent-iv)) was estimated from PK analyses of gentamicin disposition in patients with SCI. Comparisons were made between CL(gent-iv) and predictors of GFR derived from a SCI population-specific nomogram (SCI-psn), the method of Cockcroft and Gault (C-G), CL(cr-24), and a multiplicative statistical model. A multiplicative model, calculated gentamicin clearance (CL(gent-calc)), that incorporates SCI population-specific characteristics to predict CL(cr-24) and GFR was derived from a multivariate nonlinear regression analysis, and the strengths of association between CL(gent-iv) and CL(gent-calc), and estimates of GFR derived from the method of C-G, SCI-psn, and CL(cr-24) were tested. The best predictive performance was demonstrated for CL(gent-iv) and the multiplicative model, CL(gent-calc), when tested against CL(cr-24) or the SCI-psn, supporting our premise that CL(gent-iv) can be used to estimate GFR in SCI. CL(gent-iv) and CL(gent-calc) outperformed CL(cr-24), the method of C-G, and the SCI-psn as predictors of GFR. The multiplicative model produced estimates of CL(gent-iv) which were more precise and less biased than CL(cr-24), the standard radiation-free predictor of GFR in patients with SCI, the SCI-psn, and the C-G equation. In this preliminary study, the clearance of gentamicin

  12. Deposition and clearance of inhaled particles.

    PubMed Central

    Stuart, B O

    1984-01-01

    Theoretical models of respiratory tract deposition of inhaled particles are compared to experimental studies of deposition patterns in humans and animals, as governed principally by particle size, density, respiratory rate and flow parameters. Various models of inhaled particle deposition make use of approximations of the respiratory tract to predict fractional deposition caused by fundamental physical processes of particle impaction, sedimentation, and diffusion. These models for both total deposition and regional (nasopharyngeal, tracheobronchial, and pulmonary) deposition are compared with early and recent experimental studies. Reasonable correlation has been obtained between theoretical and experimental studies, but the behavior in the respiratory tract of very fine (less than 0.1 micron) particles requires further investigation. Properties of particle shape, charge and hygroscopicity as well as the degree of respiratory tract pathology also influence deposition patterns; definitive experimental work is needed in these areas. The influence upon deposition patterns of dynamic alterations in inspiratory flow profiles caused by a variety of breathing patterns also requires further study, and the use of differing ventilation techniques with selected inhaled particle sizes holds promise in diagnosis of respiratory tract diseases. Mechanisms of conducting airway and alveolar clearance processes involving the pulmonary macrophage, mucociliary clearance, dissolution, transport to systemic circulation, and translocation via regional lymphatic vessels are discussed. PMID:6376108

  13. Renal Clearance of Mineral Metabolism Biomarkers.

    PubMed

    van Ballegooijen, Adriana J; Rhee, Eugene P; Elmariah, Sammy; de Boer, Ian H; Kestenbaum, Bryan

    2016-02-01

    CKD leads to disturbances in multiple interrelated hormones that regulate bone and mineral metabolism. The renal handling of mineral metabolism hormones in humans is incompletely understood. We determined the single-pass renal clearance of parathyroid hormone, fibroblast growth factor 23, vitamin D metabolites, and phosphate from paired blood samples collected from the abdominal aorta and renal vein in 17 participants undergoing simultaneous right and left heart catheterization and estimated associations of eGFR with the renal elimination of metabolites. The mean age ±SD of the study population was 71.4±10.0 years and 11 participants (65%) were male. We found a relatively large mean±SD single-pass renal extraction of parathyroid hormone (44.2%±10.3%) that exceeded the extraction of creatinine (22.1%±7.9%). The proportionate renal extraction of parathyroid hormone correlated with eGFR. The renal extraction of fibroblast growth factor 23 was, on average, lower than that of parathyroid hormone with greater variability across individuals (17.1%±19.5%). There were no differences in the mean concentrations of vitamin D metabolites across the renal vein and artery. In summary, we demonstrate substantial single-pass renal extraction of parathyroid hormone at a rate that exceeds glomerular filtration. Impaired renal clearance of parathyroid hormone may contribute to secondary hyperparathyroidism in CKD. PMID:26047790

  14. Nod2 sensing of lysozyme-digested peptidoglycan promotes macrophage recruitment and clearance of S. pneumoniae colonization in mice

    PubMed Central

    Davis, Kimberly M.; Nakamura, Shigeki; Weiser, Jeffrey N.

    2011-01-01

    Streptococcus pneumoniae colonizes the mucosal surface of the human upper respiratory tract. A colonization event is gradually cleared through phagocytosis by monocytes/macrophages that are recruited to the airway lumen. Here, we sought to define the bacterial and host factors that promote monocyte/macrophage influx and S. pneumoniae clearance using intranasal bacterial challenge in mice. We found that the recruitment of monocytes/macrophages required their expression of the chemokine receptor CCR2 and correlated with expression of the CCR2 ligand CCL2. Production of CCL2 and monocyte/macrophage recruitment were deficient in mice lacking digestion of peptidoglycan by lysozyme (LysM) and cytosolic sensing of the products of digestion by Nod2. Ex vivo macrophages produced CCL2 following bacterial uptake, digestion by LysM, and sensing of peptidoglycan by Nod2. Sensing of digested peptidoglycan by Nod2 also required the pore-forming toxin pneumolysin. The generation of an adaptive immune response, as measured by anti-pneumococcal antibody titers, was also LysM- and Nod2-dependent. Together, our data suggest that bacterial uptake by professional phagocytes is followed by LysM-mediated digestion of S. pneumoniae–derived peptidoglycan, sensing of the resulting products by Nod2, release of the chemokine CCL2, and CCR2-dependent recruitment of the additional monocytes/macrophages required for the clearance of an S. pneumoniae colonization event. PMID:21841315

  15. ESR measurement of radical clearance in lung of whole mouse

    SciTech Connect

    Takeshita, K.; Utsumi, H.; Hamada, A. )

    1991-06-14

    Clearance of the nitroxide radicals, hydroxy-TEMPO and carboxy-PROxYL, in whole-mouse lung was directly measured by in vivo ESR. After injecting a nitroxide radical, distribution of the nitroxide radical all over the lung was confirmed by ESR imaging. The ESR signal of hydroxy-TEMPO was reduced in the lung and the clearance obeyed first-order kinetics, whereas the signal of carboxy-PROxYL remained constant. Comparison of the clearance rates of live and dead mice indicated the presence of 2 different clearance systems in the lung: loss of its paramagnetism in the lung, and transfer from alveolar to the blood circulation system.

  16. Fuel conservation through active control of rotor clearances

    NASA Technical Reports Server (NTRS)

    Beitler, R. S.; Saunders, A. A.; Wanger, R. P.

    1980-01-01

    Under the NASA-sponsored Energy Efficient Engine (EEE) Project, technology is being developed which will significantly reduce the fuel consumption of turbofan engines for subsonic transport aircraft. One technology concept being pursued is active control of rotor tip clearances. Attention is given to rotor tip clearance considerations and an overview of preliminary study results as well as the General Electric EEE clearance control approach is presented. Finally, potential fuel savings with active control of rotor clearances for a typical EEE mission are predicted.

  17. Bacterial vaginosis.

    PubMed Central

    Spiegel, C A

    1991-01-01

    Bacterial vaginosis (BV) is the most common of the vaginitides affecting women of reproductive age. It appears to be due to an alteration in the vaginal ecology by which Lactobacillus spp., the predominant organisms in the healthy vagina, are replaced by a mixed flora including Prevotella bivia, Prevotella disiens, Porphyromonas spp., Mobiluncus spp., and Peptostreptococcus spp. All of these organisms except Mobiluncus spp. are also members of the endogenous vaginal flora. While evidence from treatment trials does not support the notion that BV is sexually transmitted, recent studies have shown an increased risk associated with multiple sexual partners. It has also been suggested that the pathogenesis of BV may be similar to that of urinary tract infections, with the rectum serving as a reservoir for some BV-associated flora. The organisms associated with BV have also been recognized as agents of female upper genital tract infection, including pelvic inflammatory disease, and the syndrome BV has been associated with adverse outcome of pregnancy, including premature rupture of membranes, chorioamnionitis, and fetal loss; postpartum endometritis; cuff cellulitis; and urinary tract infections. The mechanisms by which the BV-associated flora causes the signs of BV are not well understood, but a role for H2O2-producing Lactobacillus spp. in protecting against colonization by catalase-negative anaerobic bacteria has been recognized. These and other aspects of BV are reviewed. PMID:1747864

  18. Trappin-2 promotes early clearance of Pseudomonas aeruginosa through CD14-dependent macrophage activation and neutrophil recruitment.

    PubMed

    Wilkinson, Thomas S; Dhaliwal, Kevin; Hamilton, Thomas W; Lipka, Alexander F; Farrell, Lesley; Davidson, Donald J; Duffin, Rodger; Morris, Andrew Conway; Haslett, Chris; Govan, John R W; Gregory, Christopher D; Sallenave, Jean-Michel; Simpson, A John

    2009-04-01

    Microaspiration of Pseudomonas aeruginosa contributes to the pathogenesis of nosocomial pneumonia. Trappin-2 is a host defense peptide that assists with the clearance of P. aeruginosa through undefined mechanisms. A model of macrophage interactions with replicating P. aeruginosa (strain PA01) in serum-free conditions was developed, and the influence of subantimicrobial concentrations of trappin-2 was subsequently studied. PA01 that was pre-incubated with trappin-2 (at concentrations that have no direct antimicrobial effects), but not control PA01, was cleared by alveolar and bone marrow-derived macrophages. However, trappin-2-enhanced clearance of PA01 was completely abrogated by CD14- null macrophages. Fluorescence microscopy demonstrated the presence of trappin-2 on the bacterial cell surface of trappin-2-treated PA01. In a murine model of early lung infection, trappin-2-treated PA01 was cleared more efficiently than control PA01 2 hours of intratracheal instillation. Furthermore, trappin-2-treated PA01 up-regulated the murine chemokine CXCL1/KC after 2 hours with a corresponding increase in neutrophil recruitment 1 hour later. These in vivo trappin-2-treated PA01 effects were absent in CD14-deficient mice. Trappin-2 appears to opsonize P. aeruginosa for more efficient, CD14-dependent clearance by macrophages and contributes to the induction of chemokines that promote neutrophil recruitment. Trappin-2 may therefore play an important role in innate recognition and clearance of pathogens during the very earliest stages of pulmonary infection. PMID:19264904

  19. Trappin-2 Promotes Early Clearance of Pseudomonas aeruginosa through CD14-Dependent Macrophage Activation and Neutrophil Recruitment

    PubMed Central

    Wilkinson, Thomas S.; Dhaliwal, Kevin; Hamilton, Thomas W.; Lipka, Alexander F.; Farrell, Lesley; Davidson, Donald J.; Duffin, Rodger; Morris, Andrew Conway; Haslett, Chris; Govan, John R.W.; Gregory, Christopher D.; Sallenave, Jean-Michel; Simpson, A. John

    2009-01-01

    Microaspiration of Pseudomonas aeruginosa contributes to the pathogenesis of nosocomial pneumonia. Trappin-2 is a host defense peptide that assists with the clearance of P. aeruginosa through undefined mechanisms. A model of macrophage interactions with replicating P. aeruginosa (strain PA01) in serum-free conditions was developed, and the influence of subantimicrobial concentrations of trappin-2 was subsequently studied. PA01 that was pre-incubated with trappin-2 (at concentrations that have no direct antimicrobial effects), but not control PA01, was cleared by alveolar and bone marrow-derived macrophages. However, trappin-2-enhanced clearance of PA01 was completely abrogated by CD14- null macrophages. Fluorescence microscopy demonstrated the presence of trappin-2 on the bacterial cell surface of trappin-2-treated PA01. In a murine model of early lung infection, trappin-2-treated PA01 was cleared more efficiently than control PA01 2 hours of intratracheal instillation. Furthermore, trappin-2-treated PA01 up-regulated the murine chemokine CXCL1/KC after 2 hours with a corresponding increase in neutrophil recruitment 1 hour later. These in vivo trappin-2-treated PA01 effects were absent in CD14-deficient mice. Trappin-2 appears to opsonize P. aeruginosa for more efficient, CD14-dependent clearance by macrophages and contributes to the induction of chemokines that promote neutrophil recruitment. Trappin-2 may therefore play an important role in innate recognition and clearance of pathogens during the very earliest stages of pulmonary infection. PMID:19264904

  20. Lung epithelial MyD88 drives early pulmonary clearance of Pseudomonas aeruginosa by a flagellin dependent mechanism.

    PubMed

    Anas, Adam A; van Lieshout, Miriam H P; Claushuis, Theodora A M; de Vos, Alex F; Florquin, Sandrine; de Boer, Onno J; Hou, Baidong; Van't Veer, Cornelis; van der Poll, Tom

    2016-08-01

    Pseudomonas aeruginosa is a flagellated pathogen frequently causing pneumonia in hospitalized patients and sufferers of chronic lung disease. Here we investigated the role of the common Toll-like receptor (TLR) adaptor myeloid differentiation factor (MyD)88 in myeloid vs. lung epithelial cells in clearance of P. aeruginosa from the airways. Mice deficient for MyD88 in lung epithelial cells (Sftpccre-MyD88-lox mice) or myeloid cells (LysMcre-MyD88-lox mice) and bone marrow chimeric mice deficient for TLR5 (the receptor recognizing Pseudomonas flagellin) in either parenchymal or hematopoietic cells were infected with P. aeruginosa via the airways. Sftpccre-MyD88-lox mice demonstrated a reduced influx of neutrophils into the bronchoalveolar space and an impaired early antibacterial defense after infection with P. aeruginosa, whereas the response of LysMcre-MyD88-lox mice did not differ from control mice. The immune-enhancing role of epithelial MyD88 was dependent on recognition of pathogen-derived flagellin by epithelial TLR5, as demonstrated by an unaltered clearance of mutant P. aeruginosa lacking flagellin from the lungs of Sftpccre-MyD88-lox mice and an impaired bacterial clearance in bone marrow chimeric mice lacking TLR5 in parenchymal cells. These data indicate that early clearance of P. aeruginosa from the airways is dependent on flagellin-TLR5-MyD88-dependent signaling in respiratory epithelial cells. PMID:27288486

  1. The Clearance of Creatinine, Inulin, Para-aminohippurate and Phenosulphothalein in the Cat

    PubMed Central

    Osbaldiston, G. W.; Fuhrman, W.

    1970-01-01

    Endogenous creatinine, inulin, para-amino-hippurate and phenolsulphothalein clearances for healthy cats are presented. The values for inulin and para-aminohippurate clearances (ml/kg/min) are similar to those for the dog. Creatinine clearance was less than inulin clearance values. Pnenolsulphothalein clearance may be a better index of glomerular rather than tubular function in the cat. PMID:4246836

  2. Bacterial interference with canonical NFκB signalling

    PubMed Central

    Askarian, Fatemeh; Sangvik, Maria; Sollid, Johanna E.

    2013-01-01

    The human body is constantly challenged by a variety of commensal and pathogenic micro-organisms that trigger the immune system. Central in the first line of defence is the pattern-recognition receptor (PRR)-induced stimulation of the NFκB pathway, leading to NFκB activation. The subsequent production of pro-inflammatory cytokines and/or antimicrobial peptides results in recruitment of professional phagocytes and bacterial clearance. To overcome this, bacteria have developed mechanisms for targeted interference in every single step in the PRR–NFκB pathway to dampen host inflammatory responses. This review aims to briefly overview the PRR–NFκB pathway in relation to the immune response and give examples of the diverse bacterial evasion mechanisms including changes in the bacterial surface, decoy production and injection of effector molecules. Targeted regulation of inflammatory responses is needed and bacterial molecules developed for immune evasion could provide future anti-inflammatory agents. PMID:23873783

  3. Interactions between Autophagy and Bacterial Toxins: Targets for Therapy?

    PubMed Central

    Mathieu, Jacques

    2015-01-01

    Autophagy is a physiological process involved in defense mechanisms for clearing intracellular bacteria. The autophagic pathway is finely regulated and bacterial toxins interact with this process in a complex manner. Bacterial toxins also interact significantly with many biochemical processes. Evaluations of the effects of bacterial toxins, such as endotoxins, pore-forming toxins and adenylate cyclases, on autophagy could support the development of new strategies for counteracting bacterial pathogenicity. Treatment strategies could focus on drugs that enhance autophagic processes to improve the clearance of intracellular bacteria. However, further in vivo studies are required to decipher the upregulation of autophagy and potential side effects limiting such approaches. The capacity of autophagy activation strategies to improve the outcome of antibiotic treatment should be investigated in the future. PMID:26248079

  4. Bacterial tyrosinases.

    PubMed

    Claus, Harald; Decker, Heinz

    2006-01-01

    Tyrosinases are nearly ubiquitously distributed in all domains of life. They are essential for pigmentation and are important factors in wound healing and primary immune response. Their active site is characterized by a pair of antiferromagnetically coupled copper ions, CuA and CuB, which are coordinated by six histidine residues. Such a "type 3 copper centre" is the common feature of tyrosinases, catecholoxidases and haemocycanins. It is also one of several other copper types found in the multi-copper oxidases (ascorbate oxidase, laccase). The copper pair of tyrosinases binds one molecule of atmospheric oxygen to catalyse two different kinds of enzymatic reactions: (1) the ortho-hydroxylation of monophenols (cresolase activity) and (2) the oxidation of o-diphenols to o-diquinones (catecholase activity). The best-known function is the formation of melanins from L-tyrosine via L-dihydroxyphenylalanine (L-dopa). The complicated hydroxylation mechanism at the active centre is still not completely understood, because nothing is known about their tertiary structure. One main reason for this deficit is that hitherto tyrosinases from eukaryotic sources could not be isolated in sufficient quantities and purities for detailed structural studies. This is not the case for prokaryotic tyrosinases from different Streptomyces species, having been intensively characterized genetically and spectroscopically for decades. The Streptomyces tyrosinases are non-modified monomeric proteins with a low molecular mass of ca. 30kDa. They are secreted to the surrounding medium, where they are involved in extracellular melanin production. In the species Streptomyces, the tyrosinase gene is part of the melC operon. Next to the tyrosinase gene (melC2), this operon contains an additional ORF called melC1, which is essential for the correct expression of the enzyme. This review summarizes the present knowledge of bacterial tyrosinases, which are promising models in order to get more insights in

  5. Improved Flight Test Procedures for Flutter Clearance

    NASA Technical Reports Server (NTRS)

    Lind, Rick C.; Brenner, Martin J.; Freudinger, Lawrence C.

    1997-01-01

    Flight flutter testing is an integral part of flight envelope clearance. This paper discusses advancements in several areas that are being investigated to improve efficiency and safety of flight test programs. Results are presented from recent flight testing of the F/A-18 Systems Research Aircraft. A wingtip excitation system was used to generate aeroelastic response data. This system worked well for many flight conditions but still displayed some anomalies. Wavelet processing is used to analyze the flight data. Filtered transfer functions are generated that greatly improve system identification. A flutter margin is formulated that accounts for errors between a model and flight data. Worst-case flutter margins are computed to demonstrate the flutter boundary may lie closer to the flight envelope than previously estimated. This paper concludes with developments for a distributed flight analysis environment and on-line health monitoring.

  6. Validation of Dose Calculation Codes for Clearance

    SciTech Connect

    Menon, S.; Wirendal, B.; Bjerler, J.; Studsvik; Teunckens, L.

    2003-02-27

    Various international and national bodies such as the International Atomic Energy Agency, the European Commission, the US Nuclear Regulatory Commission have put forward proposals or guidance documents to regulate the ''clearance'' from regulatory control of very low level radioactive material, in order to allow its recycling as a material management practice. All these proposals are based on predicted scenarios for subsequent utilization of the released materials. The calculation models used in these scenarios tend to utilize conservative data regarding exposure times and dose uptake as well as other assumptions as a safeguard against uncertainties. None of these models has ever been validated by comparison with the actual real life practice of recycling. An international project was organized in order to validate some of the assumptions made in these calculation models, and, thereby, better assess the radiological consequences of recycling on a practical large scale.

  7. Allometric scaling for predicting human clearance of bisphenol A

    SciTech Connect

    Collet, Séverine H. Picard-Hagen, Nicole Lacroix, Marlène Z. Puel, Sylvie Viguié, Catherine Bousquet-Melou, Alain Toutain, Pierre-Louis Gayrard, Véronique

    2015-05-01

    The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. - Highlights: • Allometric scaling was used to predict BPA pharmacokinetic parameters in humans. • In all species, BPA plasma clearance approached hepatic blood flow. • Human BPA clearance was estimated to be 1.79 L/min.

  8. 10 CFR 95.17 - Processing facility clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... concerning the foreign intelligence threat, risk of unauthorized technology transfer, type and sensitivity of... SECURITY INFORMATION AND RESTRICTED DATA Physical Security § 95.17 Processing facility clearance. (a... related classified information, or process the facility for a facility clearance. Processing will...

  9. 20 CFR 655.150 - Interstate clearance of job order.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated...

  10. 20 CFR 655.150 - Interstate clearance of job order.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated...

  11. 20 CFR 655.150 - Interstate clearance of job order.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated...

  12. 20 CFR 655.150 - Interstate clearance of job order.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated...

  13. 20 CFR 655.150 - Interstate clearance of job order.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Interstate clearance of job order. 655.150... job order. (a) SWA posts in interstate clearance system. The SWA must promptly place the job order in... transmit a copy of its active job order to all States listed in the job order as anticipated...

  14. 48 CFR 245.7203 - Assigning plant clearance case numbers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Assigning plant clearance case numbers. 245.7203 Section 245.7203 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT GOVERNMENT PROPERTY Special Instructions 245.7203 Assigning plant clearance case...

  15. Study of global operational needs for mine clearance equipment

    NASA Astrophysics Data System (ADS)

    Blagden, Paddy M.

    2003-09-01

    The Geneva International Centre for Humanitarian Demining studied the needs of landmine clearance groups for equipment to carry out specific functions of mine clearance. This was done on a global level, and useful results were obtained, which will provide the basis for further analysis.

  16. 48 CFR 245.7202 - Establishing a plant clearance case.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Establishing a plant clearance case. 245.7202 Section 245.7202 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT GOVERNMENT PROPERTY Special Instructions 245.7202 Establishing a plant clearance case....

  17. Benefits of Improved HP Turbine Active Clearance Control

    NASA Technical Reports Server (NTRS)

    Ruiz, Rafael; Albers, Bob; Sak, Wojciech; Seitzer, Ken; Steinetz, Bruce M.

    2007-01-01

    As part of the NASA Propulsion 21 program, GE Aircraft Engines was contracted to develop an improved high pressure turbine(HPT) active clearance control (ACC) system. The system is envisioned to minimize blade tip clearances to improve HPT efficiency throughout the engine operation range simultaneously reducing fuel consumption and emissions.

  18. Mechanistic evaluation of virus clearance by depth filtration.

    PubMed

    Venkiteshwaran, Adith; Fogle, Jace; Patnaik, Purbasa; Kowle, Ron; Chen, Dayue

    2015-01-01

    Virus clearance by depth filtration has not been well-understood mechanistically due to lack of quantitative data on filter charge characteristics and absence of systematic studies. It is generally believed that both electrostatic interactions and sized based mechanical entrapment contribute to virus clearance by depth filtration. In order to establish whether the effectiveness of virus clearance correlates with the charge characteristics of a given depth filter, a counter-ion displacement technique was employed to determine the ionic capacity for several depth filters. Two depth filters (Millipore B1HC and X0HC) with significant differences in ionic capacities were selected and evaluated for their ability to eliminate viruses. The high ionic capacity X0HC filter showed complete porcine parvovirus (PPV) clearance (eliminating the spiked viruses to below the limit of detection) under low conductivity conditions (≤2.5 mS/cm), achieving a log10 reduction factor (LRF) of > 4.8. On the other hand, the low ionic capacity B1HC filter achieved only ∼2.1-3.0 LRF of PPV clearance under the same conditions. These results indicate that parvovirus clearance by these two depth filters are mainly achieved via electrostatic interactions between the filters and PPV. When much larger xenotropic murine leukemia virus (XMuLV) was used as the model virus, complete retrovirus clearance was obtained under all conditions evaluated for both depth filters, suggesting the involvement of mechanisms other than just electrostatic interactions in XMuLV clearance. PMID:25683459

  19. 32 CFR 644.522 - Clearance of military scrap.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Clearance of military scrap. 644.522 Section 644.522 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  20. 32 CFR 644.521 - Limitations on clearance cost.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Limitations on clearance cost. 644.521 Section 644.521 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  1. 32 CFR 644.522 - Clearance of military scrap.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Clearance of military scrap. 644.522 Section 644.522 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  2. 32 CFR 644.521 - Limitations on clearance cost.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Limitations on clearance cost. 644.521 Section 644.521 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  3. 32 CFR 644.527 - Recording Statements of Clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Recording Statements of Clearance. 644.527 Section 644.527 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  4. 32 CFR 644.527 - Recording Statements of Clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Recording Statements of Clearance. 644.527 Section 644.527 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  5. 14 CFR 375.24 - Entry and clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Entry and clearance. 375.24 Section 375.24 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS NAVIGATION OF FOREIGN CIVIL AIRCRAFT WITHIN THE UNITED STATES Rules Generally Applicable § 375.24 Entry and clearance. All...

  6. 48 CFR 945.603-70 - Plant clearance function.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Plant clearance function. 945.603-70 Section 945.603-70 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT MANAGEMENT GOVERNMENT PROPERTY Reporting, Redistribution, and Disposal of Contractor Inventory 945.603-70 Plant clearance function. If the...

  7. 76 FR 17978 - Agency Information Collection Activities: Emergency Clearance Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-31

    ... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY ADMINISTRATION Agency Information Collection Activities: Emergency Clearance Request The Social Security Administration (SSA) publishes a list of information collection packages requiring clearance by the Office of Management and Budget (OMB) in compliance...

  8. 5 CFR 720.307 - Interagency report clearance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Interagency report clearance. 720.307 Section 720.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) AFFIRMATIVE EMPLOYMENT PROGRAMS Disabled Veterans Affirmative Action Program § 720.307 Interagency report clearance. The...

  9. 33 CFR 160.115 - Withholding of clearance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Withholding of clearance. 160.115 Section 160.115 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY PORTS AND WATERWAYS SAFETY-GENERAL Control of Vessel and Facility Operations § 160.115 Withholding of clearance....

  10. 30 CFR 57.19104 - Clearance at shaft stations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance at shaft stations. 57.19104 Section 57.19104 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Personnel Hoisting Shafts § 57.19104 Clearance at...

  11. 30 CFR 56.19104 - Clearance at shaft stations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance at shaft stations. 56.19104 Section 56.19104 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Personnel Hoisting Shafts § 56.19104 Clearance at...

  12. 19 CFR 122.158 - Other entry and clearance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Other entry and clearance requirements. 122.158 Section 122.158 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Flights to and From Cuba § 122.158 Other entry and clearance requirements. All other provisions...

  13. 48 CFR 32.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  14. 48 CFR 32.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  15. 48 CFR 1432.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  16. 48 CFR 832.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  17. 48 CFR 832.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  18. 48 CFR 1432.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  19. Clearance systems in the brain-implications for Alzheimer disease.

    PubMed

    Tarasoff-Conway, Jenna M; Carare, Roxana O; Osorio, Ricardo S; Glodzik, Lidia; Butler, Tracy; Fieremans, Els; Axel, Leon; Rusinek, Henry; Nicholson, Charles; Zlokovic, Berislav V; Frangione, Blas; Blennow, Kaj; Ménard, Joël; Zetterberg, Henrik; Wisniewski, Thomas; de Leon, Mony J

    2015-08-01

    Accumulation of toxic protein aggregates-amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles-is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood-brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ. PMID:26195256

  20. 49 CFR 229.71 - Clearance above top of rail.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Clearance above top of rail. 229.71 Section 229.71....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail....

  1. 49 CFR 229.71 - Clearance above top of rail.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Clearance above top of rail. 229.71 Section 229.71....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail....

  2. 49 CFR 229.71 - Clearance above top of rail.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Clearance above top of rail. 229.71 Section 229.71....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail....

  3. 49 CFR 229.71 - Clearance above top of rail.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Clearance above top of rail. 229.71 Section 229.71....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail....

  4. 49 CFR 229.71 - Clearance above top of rail.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Clearance above top of rail. 229.71 Section 229.71....71 Clearance above top of rail. No part or appliance of a locomotive except the wheels, flexible nonmetallic sand pipe extension tips, and trip cock arms may be less than 21/2 inches above the top of rail....

  5. 33 CFR 118.160 - Vertical clearance gauges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Vertical clearance gauges. 118.160 Section 118.160 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.160 Vertical clearance gauges. (a) When necessary for reasons of safety of navigation, the...

  6. Radioaerosol delivery and clearance in patients with respiratory failure

    SciTech Connect

    Jacobs, M.P.; Tennenberg, S.D.; Baughman, R.P.

    1987-12-01

    A technique for radioaerosol delivery to patients requiring mechanical ventilation is described. Ventilation images and pulmonary radioaerosol clearance rates were successfully obtained in 35 patients regardless of ventilator type or level of positive end-expiratory pressure (PEEP). Those patients with noncardiogenic pulmonary edema (NPE) had significantly increased clearance rates relative to those patients in whom NPE was not present.

  7. 32 CFR 644.516 - Clearance of Air Force lands.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Clearance of Air Force lands. 644.516 Section 644... Excess Land and Improvements § 644.516 Clearance of Air Force lands. The Chief of Engineers has no responsibility for inspecting or clearing excess Air Force land of explosives or chemical/biological...

  8. 32 CFR 644.516 - Clearance of Air Force lands.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Clearance of Air Force lands. 644.516 Section 644... Excess Land and Improvements § 644.516 Clearance of Air Force lands. The Chief of Engineers has no responsibility for inspecting or clearing excess Air Force land of explosives or chemical/biological...

  9. 32 CFR 644.516 - Clearance of Air Force lands.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Clearance of Air Force lands. 644.516 Section... Excess Land and Improvements § 644.516 Clearance of Air Force lands. The Chief of Engineers has no responsibility for inspecting or clearing excess Air Force land of explosives or chemical/biological...

  10. 32 CFR 644.516 - Clearance of Air Force lands.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Clearance of Air Force lands. 644.516 Section... Excess Land and Improvements § 644.516 Clearance of Air Force lands. The Chief of Engineers has no responsibility for inspecting or clearing excess Air Force land of explosives or chemical/biological...

  11. 32 CFR 644.516 - Clearance of Air Force lands.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Clearance of Air Force lands. 644.516 Section 644... Excess Land and Improvements § 644.516 Clearance of Air Force lands. The Chief of Engineers has no responsibility for inspecting or clearing excess Air Force land of explosives or chemical/biological...

  12. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ground clearance: tail rotor guard. 29.411 Section 29.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  13. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ground clearance: tail rotor guard. 29.411 Section 29.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  14. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ground clearance: tail rotor guard. 29.411 Section 29.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  15. 14 CFR 27.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ground clearance: tail rotor guard. 27.411 Section 27.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 27.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  16. 14 CFR 27.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ground clearance: tail rotor guard. 27.411 Section 27.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 27.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  17. 14 CFR 27.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ground clearance: tail rotor guard. 27.411 Section 27.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 27.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  18. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ground clearance: tail rotor guard. 29.411 Section 29.411 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor...

  19. Clearance systems in the brain—implications for Alzheimer disease

    PubMed Central

    Tarasoff-Conway, Jenna M.; Carare, Roxana O.; Osorio, Ricardo S.; Glodzik, Lidia; Butler, Tracy; Fieremans, Els; Axel, Leon; Rusinek, Henry; Nicholson, Charles; Zlokovic, Berislav V.; Frangione, Blas; Blennow, Kaj; Ménard, Joël; Zetterberg, Henrik; Wisniewski, Thomas; de Leon, Mony J.

    2015-01-01

    Accumulation of toxic protein aggregates—amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles—is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood–brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ. PMID:26195256

  20. 50 CFR 14.52 - Clearance of imported wildlife.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 1 2011-10-01 2011-10-01 false Clearance of imported wildlife. 14.52....52 Clearance of imported wildlife. (a) Except as otherwise provided by this subpart, a Service officer must clear all wildlife imported into the United States prior to release from detention by...

  1. 14 CFR 27.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground clearance: tail rotor guard. 27.411... System Loads § 27.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor to contact the landing surface during a normal landing. (b) If a tail rotor guard is required to...

  2. 14 CFR 29.411 - Ground clearance: tail rotor guard.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ground clearance: tail rotor guard. 29.411... System Loads § 29.411 Ground clearance: tail rotor guard. (a) It must be impossible for the tail rotor to contact the landing surface during a normal landing. (b) If a tail rotor guard is required to...

  3. 48 CFR 32.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  4. 48 CFR 1432.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  5. 48 CFR 1432.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  6. 48 CFR 1432.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Contract finance office clearance. 1432.502-2 Section 1432.502-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... finance office clearance. The CO shall obtain approval of the bureau finance office prior to...

  7. 48 CFR 832.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  8. 48 CFR 32.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  9. 48 CFR 832.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  10. 48 CFR 32.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Contract finance office clearance. 32.502-2 Section 32.502-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... finance office clearance. The contracting officer shall obtain the approval of the contract finance...

  11. 48 CFR 832.502-2 - Contract finance office clearance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Contract finance office clearance. 832.502-2 Section 832.502-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... finance office clearance. Contracting officers must obtain approval from the DSPE before taking...

  12. 32 CFR 644.527 - Recording Statements of Clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Recording Statements of Clearance. 644.527 Section 644.527 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  13. 32 CFR 644.527 - Recording Statements of Clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Recording Statements of Clearance. 644.527 Section 644.527 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  14. 32 CFR 644.521 - Limitations on clearance cost.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Limitations on clearance cost. 644.521 Section 644.521 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  15. 32 CFR 644.522 - Clearance of military scrap.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Clearance of military scrap. 644.522 Section 644.522 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  16. 32 CFR 644.521 - Limitations on clearance cost.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Limitations on clearance cost. 644.521 Section 644.521 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  17. 32 CFR 644.527 - Recording Statements of Clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Recording Statements of Clearance. 644.527 Section 644.527 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  18. 32 CFR 644.522 - Clearance of military scrap.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Clearance of military scrap. 644.522 Section 644.522 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  19. 32 CFR 644.521 - Limitations on clearance cost.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Limitations on clearance cost. 644.521 Section 644.521 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  20. 32 CFR 644.522 - Clearance of military scrap.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Clearance of military scrap. 644.522 Section 644.522 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Clearance of Explosive Hazards and Other Contamination from...

  1. Bacterial differentiation.

    PubMed

    Shapiro, L; Agabian-Keshishian, N; Bendis, I

    1971-09-01

    technique can be used to select for mutants blocked in the various stages of morphogenesis. 3) Temperature-sensitive mutants of Caulobacter that are restricted in macromolecular synthesis and development at elevated temperatures have been isolated. 4) Genetic exchange in the Calflobacter genus has been demonstrated and is now being defined. Two questions related to control processes can now readily be approached experimentally. (i) Is the temporal progression of events occurring during bacterial differentiation controlled by regulator gene products? (ii) Is the differentiation cycle like a biosynthetic pathway where one event must follow another? The availability of temperature-sensitive mutants blocked at various stages of development permits access to both questions. An interesting feature of the differentiation cycle is that the polar organelle may represent a special segregated unit which is operative in the control of the differentiation process. Perhaps the sequential morphogenic changes exhibited by Caulobacter are dependent on the initial synthesis of this organelle. Because the ultimate expression of cell changes are dependent on selective protein synthesis, specific messenger RNA production-either from DNA present in an organelle or from the chromosome-may prove to be a controlling factor in cell differentiation. We have begun studies with RNA polymerase purified from Caulobacter crescentus to determine whether cell factors or alterations in the enzyme structure serve to change the specificity of transcription during the cell cycle. Control of sequential cell changes at the level of transcription has long been postulated and has recently been substantiated in the case of Bacillus sporulation (6). The Caulobacter bacteria now present another system in which direct analysis of these control mechanisms is feasible. PMID:5572165

  2. D0 Solenoid Chimney Routing Clearances

    SciTech Connect

    Rucinski, R.; /Fermilab

    1994-02-23

    This engineering note contains information about the measured clearances along the chimney route from the solenoid to the control dewar. This type of information is best conveyed by sketches and a few photos. Twelve photos taken on 2/17/94 are included which gIVe perspective views along the path. The detector was parked in the collision hall on this date. The CF iron was split open to the east and the South EF iron was rolled back. Also the South EndCap Calorimeter was rolled to the south on this day. This allowed personnel access and the photographic opportunity. A full set of raw dimensional sketches are included. These sketches were generated by me using a 25 foot tape measure and a note pad. The sketches are in chronological order with the most recent on top. The first sketch, 5/18/94, describes the 'tightest' location for the upward incline portion of the chimney. The sketches on 2/14/94 thru 2/16/94 are refinements of the early 1992 and 1993 sketches. They pick out quite a bit more detail of specific detector components along the path. The dimensional sketches of 1992 and 1993 gave information in not as much detail and therefore gave a more constrained clearance description. Most of the information of the early sketches was jotted down on the plan view dated 10-29-92. This sketch also had some information lifted from prints which later was superseded by the 1994 sketches. I tried to label components and give views either titled 'Elevation' or 'Plan' which refers to a top view looking down. Also where I could I jotted down direction, ie. South, East etc. Hopefully with a little effort one can decifer it. The curvature of the CC was determined from a three dimensional topographical survey. This survey information is stored in an electronic drawing file 3823.111-ME-317165, 'Solenoid-CC south face 3D shape survey'. The 'z' dimensions for the radial chimney path were picked off this drawing. A curvature was then generated knowing many points by radial and z

  3. Radioaerosol lung clearance in patients with active pulmonary sarcoidosis

    SciTech Connect

    Jacobs, M.P.; Baughman, R.P.; Hughes, J.; Fernandez-Ulloa, M.

    1985-05-01

    Pulmonary radioaerosol clearance rate of /sup 99m/Tc diethylenetriamine pentacetate (DTPA) in 14 patients with untreated sarcoidosis was compared with /sup 67/Ga lung scan and increased lymphocytes in the bronchoalveolar lavage (BAL) fluid. Nine healthy nonsmoking subjects had a mean DTPA clearance rate of 1.18%/min (range, 0.54 to 1.60%/min). Eight of 14 patients with sarcoidosis had clearance rates greater than 1.60%/min. Of those 8 patients with abnormal DTPA clearance, 4 had positive gallium scans, 4 had more than 17% lymphocytes in the BAL fluid, and 3 had both tests positive. To study the cause of abnormal DTPA clearance, 23 subjects (including 3 normal controls, all 14 patients with sarcoidosis, and 6 patients with localized disease on chest roentgenogram) underwent both DTPA clearance studies and BAL for quantitation of the amount of albumin in lung fluid. There was a positive correlation between the rate of DTPA clearance and the albumin concentration in lung fluid (r = 0.87, p less than 0.01).

  4. Distribution and clearance of radioactive aerosol on the nasal mucosa.

    PubMed

    McLean, J A; Bacon, J R; Mathews, K P; Thrall, J H; Banas, J M; Hedden, J; Bayne, N K

    1984-03-01

    The distribution and clearance of aerosolized radioactive technetium 99m pertechnate in physiologic buffered saline was analyzed in four human adult asymptomatic volunteers following delivery into one nostril in the same manner as for nasal challenge testing (i.e., 0.1 ml via a 251 DeVilbiss atomizer powered by a compressor delivering 0.10 +/- 0.01 gm/spray). For comparison, squeeze bottles and spray bottles from commercial sources, a 114 and a 127 DeVilbiss atomizer, and a pipette were employed. Lateral imagery via minicomputer processing was used to determine both distribution and clearance of the radiotracer. The counts after 1 minute were lower following pipette delivery than with the other devices. None yielded discernable , wide-spread distribution of aerosol throughout the nasal cavity. Following delivery from the 251 atomizer, mean clearance at 17 minutes was 60.0%. Similar clearance rates were obtained with the other spraying methods except for lower values with the squeeze bottle. Analysis of six hour clearance studies by linear regression showed a relatively rapid initial phase, which is probably due largely to mucociliary clearance, and a prolonged late phase related to the very slow disappearance of residual material located far anteriorly in the nose. Achieving good initial retention and rapid clearance of material deposited anteriorly in the nose are desirable attributes of devices employed for administering materials intranasally. PMID:6328631

  5. Lung Edema Clearance: Relevance to Patients with Lung Injury

    PubMed Central

    Azzam, Zaher S.; Sznajder, Jacob I.

    2015-01-01

    Pulmonary edema clearance is necessary for patients with lung injury to recover and survive. The mechanisms regulating edema clearance from the lungs are distinct from the factors contributing edema formation during injury. Edema clearance is effected via vectorial transport of Na+ out of the airspaces which generates an osmotic gradient causing water to follow the gradient out of the cells. This Na+ transport across the alveolar epithelium is mostly effected via apical Na+ and chloride channels and basolateral Na,K-ATPase. The Na,K-ATPase pumps Na+ out of the cell and K+ into the cell against their respective gradients in an ATP-consuming reaction. Two mechanisms contribute to the regulation of the Na,K-ATPase activity:recruitment of its subunits from intracellular compartments into the basolateral membrane, and transcriptional/translational regulation. Na,K-ATPase activity and edema clearance are increased by catecholamines, aldosterone, vasopressin, overexpression of the pump genes, and others. During lung injury, mechanisms regulating edema clearance are inhibited by yet unclear pathways. Better understanding of the mechanisms that regulate pulmonary edema clearance may lead to therapeutic interventions that counterbalance the inhibition of edema clearance during lung injury and improve the lungs’ ability to clear fluid, which is crucial for patient survival. PMID:26241220

  6. Dynamic modelling and experimental study of cantilever beam with clearance

    NASA Astrophysics Data System (ADS)

    Li, B.; Jin, W.; Han, L.; He, Z.

    2012-05-01

    Clearances occur in almost all mechanical systems, typically such as the clearance between slide plate of gun barrel and guide. Therefore, to study the clearances of mechanisms can be very important to increase the working performance and lifetime of mechanisms. In this paper, rigid dynamic modelling of cantilever with clearance was done according to the subject investigated. In the rigid dynamic modelling, clearance is equivalent to the spring-dashpot model, the impact of beam and boundary face was also taken into consideration. In ADAMS software, the dynamic simulation was carried out according to the model above. The software simulated the movement of cantilever with clearance under external excitation. Research found: When the clearance is larger, the force of impact will become larger. In order to study how the stiffness of the cantilever's supporting part influences natural frequency of the system, A Euler beam which is restricted by a draught spring and a torsion spring at its end was raised. Through numerical calculation, the relationship between natural frequency and stiffness was found. When the value of the stiffness is close to the limit value, the corresponding boundary condition is illustrated. An ADAMS experiment was carried out to check the theory and the simulation.

  7. Inter-individual variation in midazolam clearance in children

    PubMed Central

    Altamimi, Mohammed I; Sammons, Helen; Choonara, Imti

    2015-01-01

    Objectives To determine the extent of inter-individual variation in clearance of midazolam in children and establish which factors are responsible for this variation. Methods A systematic literature review was performed to identify papers describing the clearance of midazolam in children. The following databases were searched: Medline, Embase, International Pharmaceutical Abstracts, CINAHL and Cochrane Library. From the papers, the range in plasma clearance and the coefficient of variation (CV) in plasma clearance were determined. Results 25 articles were identified. Only 13 studies gave the full range of clearance values for individual patients. The CV was greater in critically ill patients (18%–170%) than non-critically ill patients (13%–54%). Inter-individual variation was a major problem in all age groups of critically ill patients. The CV was 72%–106% in preterm neonates, 18%–73% in term neonates, 31%–130% in infants, 21%–170% in children and 47%–150% in adolescents. The mean clearance was higher in children (1.1–16.7 mL/min/kg) than in neonates (0.78–2.5 mL/min/kg). Conclusions Large inter-individual variation was seen in midazolam clearance values in critically ill neonates, infants, children and adolescents. PMID:25281734

  8. Aerosol Medications for Treatment of Mucus Clearance Disorders.

    PubMed

    Rubin, Bruce K

    2015-06-01

    Airway mucus hypersecretion and secretion retention can result from inflammation, irritation, stimulation, or mucus-producing tumors. Secretion clearance can be furthered hampered by ciliary dysfunction and by weakness or restrictive lung disease, leading to an ineffective cough. There are a number of different mucoactive medications that have been used to reduce hypersecretion, make secretions easier to transport, or increase the efficiency of cough or mucus clearance. In this paper, I review the pathophysiology of secretory hyper-responsiveness and mucus hypersecretion and discuss the different aerosol medications that can be used to augment secretion clearance. PMID:26070577

  9. Time-of-Flight Tip-Clearance Measurements

    NASA Technical Reports Server (NTRS)

    Dhadwal, H. S.; Kurkov, A. P.; Janetzke, D. C.

    1999-01-01

    In this paper a time-of-flight probe system incorporating the two integrated fiber optic probes which are tilted equally relative to the probe holder centerline, is applied for the first time to measure the tip clearance of an advanced fan prototype. Tip clearance is largely independent of the signal amplitude and it relies on timing measurement. This work exposes optical effects associated with the fan blade stagger angle that were absent during the original spin-rig experiment on the zero stagger rotor. Individual blade tip clearances were measured with accuracy of +/- 127-mm (+/- 0.005-in). Probe features are discussed and improvements to the design are suggested.

  10. Toward a Fast-Response Active Turbine Tip Clearance Control

    NASA Technical Reports Server (NTRS)

    Melcher, Kevin J.; Kypuros, Javier A.

    2003-01-01

    This paper describes active tip clearance control research being conducted by NASA to improve turbine engine systems. The target application for this effort is commercial aircraft engines. However, technologies developed for clearance control can benefit a broad spectrum of current and future turbomachinery. The first portion of the paper addresses the research from a programmatic viewpoint. Recent studies that provide motivation for the work, identification of key technologies, and NASA's plan for addressing deficiencies in the technologies are discussed. The later portion of the paper drills down into one of the key technologies by presenting equations and results for a preliminary dynamic model of the tip clearance phenomena.

  11. A simplified experimental model for clearance of some pathogenic bacteria using common bacterivorous ciliated spp. in Tigris river

    NASA Astrophysics Data System (ADS)

    Ali, Talib Hassan; Saleh, Dhuha Saad

    2014-03-01

    Bacteria-specific uptake rates of three different protozoan taxa on a pure and mixed bacterial community was studied by means of a simplified and functionally reproducible experimental model. The bacterial species Shigella flexneri, Escherichia coli and Salmonella typhi were isolated and classified from stool samples of patients suffering from diarrhea. Paramecium caudatum, Tetrahymena pyriformis and Halteria grandinella, free living ciliate Protozoans, were isolated and identified from Tigris river water. Pure and mixed ( E. coli + S. typhi), ( E. coli + Sh. flexneri) bacterial cultures were used with each ciliate genera to evaluate the following: predator duplication rate, prey reduction rate, clearance rate and net grazing rate. We used selective lactose fermentation phenomena of enteric bacteria on MacConkey medium for the quantification of bacteria cultural characteristics. The final bacteria concentration was reduced by growing protozoa of 98-99.9 % compared to protozoa-free controls. It showed that Tetrahymena pyriformis had the highest duplication rate (4.13 time/day) in both types of cultures (pure and mixed), followed by Paramecium caudatum and Halteria grandinella, respectively. Paramecium caudatum had the highest rate of ingestion in both types of cultures (26 × 103 bacteria/organism/hr) and yielded the longest time required for 90 % bacterial reduction in a pure suspension of S. typhi (166 h). Clearance rates of pathogenic bacteria by ciliates ranged between 106 nanoliter/organism/h by P. caudatum to S. typhi and 1.92 nanoliter/organism/h seen in T. pyriformis in ( E. coli + S. typhi) mixed culture. We used aquatic experimental microcosms under controlled conditions to explore bacteria-dependent ciliate growth and examined whether these ciliates could discriminate between equally sized bacterial preys in a mixture.

  12. Bacterial Sphingomyelinases and Phospholipases as Virulence Factors.

    PubMed

    Flores-Díaz, Marietta; Monturiol-Gross, Laura; Naylor, Claire; Alape-Girón, Alberto; Flieger, Antje

    2016-09-01

    Bacterial sphingomyelinases and phospholipases are a heterogeneous group of esterases which are usually surface associated or secreted by a wide variety of Gram-positive and Gram-negative bacteria. These enzymes hydrolyze sphingomyelin and glycerophospholipids, respectively, generating products identical to the ones produced by eukaryotic enzymes which play crucial roles in distinct physiological processes, including membrane dynamics, cellular signaling, migration, growth, and death. Several bacterial sphingomyelinases and phospholipases are essential for virulence of extracellular, facultative, or obligate intracellular pathogens, as these enzymes contribute to phagosomal escape or phagosomal maturation avoidance, favoring tissue colonization, infection establishment and progression, or immune response evasion. This work presents a classification proposal for bacterial sphingomyelinases and phospholipases that considers not only their enzymatic activities but also their structural aspects. An overview of the main physiopathological activities is provided for each enzyme type, as are examples in which inactivation of a sphingomyelinase- or a phospholipase-encoding gene impairs the virulence of a pathogen. The identification of sphingomyelinases and phospholipases important for bacterial pathogenesis and the development of inhibitors for these enzymes could generate candidate vaccines and therapeutic agents, which will diminish the impacts of the associated human and animal diseases. PMID:27307578

  13. Metabolic clearance rate and urinary clearance of purified beta-core

    SciTech Connect

    Wehmann, R.E.; Blithe, D.L.; Flack, M.R.; Nisula, B.C. )

    1989-09-01

    We injected a highly purified preparation of the beta-core molecule, a fragment of hCG beta excreted in pregnancy urine, into five men and three women to determine its kinetic parameters, MCR, and urinary clearance. The beta-core molecule was distributed in an initial volume (1950 +/- 156 (mean +/- SEM) mL/m2 body surface area) approximately equal to the estimated plasma volume. Its disappearance was multiexponential on a semilogarithmic plot, with a rapid phase t1/2 of 3.5 +/- 0.7 min and a slow phase t1/2 of 22.4 +/- 4.2 min. The transit time (the mean time spent by a molecule of beta-core in transit) was 20.6 +/- 2.1 min. The MCR was 192.0 +/- 8.0 mL/min.m2 body surface area. About 5% of the injected dose of beta-core was excreted into the urine in the first 30 min after injection, and low levels of excretion persisted for up to 7 days. The urinary clearance rate of beta-core was 13.7 +/- 1.4 mL/min.m2, accounting for about 8% of the elimination of beta-core from the plasma. The beta-core immunoreactivity in serum and urine was characterized by gel filtration and three independent RIA systems to show that its properties were indistinguishable from those of the injected beta-core. Serum levels of beta-core in pregnant women were less than 0.2 ng/mL, while the amounts excreted in their urine were as much as 5 mg/day. Based on these clearance parameters of beta-core in normal subjects, less than 0.2% of the beta-core excreted in pregnancy urine is derived by urinary clearance of plasma beta-core. Therefore, more than 99% of the beta-core excreted in pregnancy urine is derived from beta-core in a compartment separate from plasma. In particular, these data indicate that there is relatively little placental secretion of beta-core into plasma and that placental secretion does not account for the vast majority of beta-core in pregnancy urine.

  14. Cytomegalovirus generates long-lived antigen-specific NK cells with diminished bystander activation to heterologous infection

    PubMed Central

    Min-Oo, Gundula

    2014-01-01

    Natural killer (NK) cells play a key role in the host response to cytomegalovirus (CMV) and can mediate an enhanced response to secondary challenge with CMV. We assessed the ability of mouse CMV (MCMV)–induced memory Ly49H+ NK cells to respond to challenges with influenza, an acute viral infection localized to the lung, and Listeria monocytogenes, a systemic bacterial infection. MCMV-memory NK cells did not display enhanced activation or proliferation after infection with influenza or Listeria, as compared with naive Ly49H+ or Ly49H− NK cells. Memory NK cells also showed impaired activation compared with naive cells when challenged with a mutant MCMV lacking m157, highlighting their antigen-specific response. Ex vivo, MCMV-memory NK cells displayed reduced phosphorylation of STAT4 and STAT1 in response to stimulation by IL-12 and type I interferon (IFN), respectively, and IFN-γ production was reduced in response to IL-12 + IL-18 compared with naive NK cells. However, costimulation of MCMV-memory NK cells with IL-12 and m157 antigen rescues their impaired response compared with cytokines alone. These findings reveal that MCMV-primed memory NK cells are diminished in their response to cytokine-driven bystander responses to heterologous infections as they become specialized and antigen-specific for the control of MCMV upon rechallenge. PMID:25422494

  15. Diminished virulence of a sar-/agr- mutant of Staphylococcus aureus in the rabbit model of endocarditis.

    PubMed Central

    Cheung, A L; Eberhardt, K J; Chung, E; Yeaman, M R; Sullam, P M; Ramos, M; Bayer, A S

    1994-01-01

    Microbial pathogenicity in Staphylococcus aureus is a complex process involving a number of virulence genes that are regulated by global regulatory systems including sar and agr. To evaluate the roles of these two loci in virulence, we constructed sar-/agr- mutants of strains RN6390 and RN450 and compared their phenotypic profiles to the corresponding single sar- and agr- mutants and parents. The secretion of all hemolysins was absent in the sar-/agr- mutants while residual beta-hemolysin activity remained in single agr- mutants. The fibronectin binding capacity was significantly diminished in both single sar- mutants and double mutants when compared with parents while the reduction in fibrinogen binding capacity in the double mutants was modest. In the rabbit endocarditis model, there was a significant decrease in both infectivity rates and intravegetation bacterial densities with the double mutant as compared to the parent (RN6390) at 10(3)-10(6) CFU inocula despite comparable levels of early bacteremia among various challenge groups. Notably, fewer bacteria in the double mutant group adhered to valvular vegetations at 30 min after challenge (10(6) CFU) than the parent group. These studies suggest that both the sar and agr loci are involved in initial valvular adherence, intravegetation persistence and multiplication of S. aureus in endocarditis. Images PMID:7962526

  16. Streptococcal pyrogenic exotoxin B inhibits apoptotic cell clearance by macrophages through protein S cleavage.

    PubMed

    Chen, Chia-Ling; Wu, Yueh-Ying; Lin, Chiou-Feng; Kuo, Chih-Feng; Han, Chia-Li; Wang, Shuying; Chuang, Woei-Jer; Chen, Chiu-Yueh; Wu, Jiunn-Jong; Tsai, Pei-Jane; Liu, Ching-Chuan; Lin, Yee-Shin

    2016-01-01

    Clearance of apoptotic cells by macrophages plays an important role in maintaining tissue homeostasis. Previous study indicated that streptococcal pyrogenic exotoxin B (SPE B) reduces phagocytic activity in group A streptococcus (GAS) infection. Here, we demonstrate that SPE B causes an inhibitory effect on protein S-mediated phagocytosis. In the presence of SPE B, serum- and purified protein S-mediated phagocytosis of apoptotic cells were significantly inhibited. The binding abilities of protein S to apoptotic cells were decreased by treatment with SPE B. Bacterial culture supernatants from GAS NZ131 strain also caused a reduction of protein S binding to apoptotic cells, but speB mutant strain did not. SPE B directly cleaved protein S in vitro and in vivo, whereas a lower level of cleavage occurred in mice infected with a speB isogenic mutant strain. SPE B-mediated initial cleavage of protein S caused a disruption of phagocytosis, and also resulted in a loss of binding ability of protein S-associated C4b-binding protein to apoptotic cells. Taken together, these results suggest a novel pathogenic role of SPE B that initiates protein S degradation followed by the inhibition of apoptotic cell clearance by macrophages. PMID:27181595

  17. Streptococcal pyrogenic exotoxin B inhibits apoptotic cell clearance by macrophages through protein S cleavage

    PubMed Central

    Chen, Chia-Ling; Wu, Yueh-Ying; Lin, Chiou-Feng; Kuo, Chih-Feng; Han, Chia-Li; Wang, Shuying; Chuang, Woei-Jer; Chen, Chiu-Yueh; Wu, Jiunn-Jong; Tsai, Pei-Jane; Liu, Ching-Chuan; Lin, Yee-Shin

    2016-01-01

    Clearance of apoptotic cells by macrophages plays an important role in maintaining tissue homeostasis. Previous study indicated that streptococcal pyrogenic exotoxin B (SPE B) reduces phagocytic activity in group A streptococcus (GAS) infection. Here, we demonstrate that SPE B causes an inhibitory effect on protein S-mediated phagocytosis. In the presence of SPE B, serum- and purified protein S-mediated phagocytosis of apoptotic cells were significantly inhibited. The binding abilities of protein S to apoptotic cells were decreased by treatment with SPE B. Bacterial culture supernatants from GAS NZ131 strain also caused a reduction of protein S binding to apoptotic cells, but speB mutant strain did not. SPE B directly cleaved protein S in vitro and in vivo, whereas a lower level of cleavage occurred in mice infected with a speB isogenic mutant strain. SPE B-mediated initial cleavage of protein S caused a disruption of phagocytosis, and also resulted in a loss of binding ability of protein S-associated C4b-binding protein to apoptotic cells. Taken together, these results suggest a novel pathogenic role of SPE B that initiates protein S degradation followed by the inhibition of apoptotic cell clearance by macrophages. PMID:27181595

  18. A Long-Chain Flavodoxin Protects Pseudomonas aeruginosa from Oxidative Stress and Host Bacterial Clearance

    PubMed Central

    Moyano, Alejandro J.; Krapp, Adriana R.; Mondotte, Juan A.; Bocco, José L.; Saleh, Maria-Carla; Carrillo, Néstor; Smania, Andrea M.

    2014-01-01

    Long-chain flavodoxins, ubiquitous electron shuttles containing flavin mononucleotide (FMN) as prosthetic group, play an important protective role against reactive oxygen species (ROS) in various microorganisms. Pseudomonas aeruginosa is an opportunistic pathogen which frequently has to face ROS toxicity in the environment as well as within the host. We identified a single ORF, hereafter referred to as fldP (for flavodoxin from P . aeruginosa), displaying the highest similarity in length, sequence identity and predicted secondary structure with typical long-chain flavodoxins. The gene was cloned and expressed in Escherichia coli. The recombinant product (FldP) could bind FMN and exhibited flavodoxin activity in vitro. Expression of fldP in P. aeruginosa was induced by oxidative stress conditions through an OxyR-independent mechanism, and an fldP-null mutant accumulated higher intracellular ROS levels and exhibited decreased tolerance to H2O2 toxicity compared to wild-type siblings. The mutant phenotype could be complemented by expression of a cyanobacterial flavodoxin. Overexpression of FldP in a mutT-deficient P. aeruginosa strain decreased H2O2-induced cell death and the hypermutability caused by DNA oxidative damage. FldP contributed to the survival of P. aeruginosa within cultured mammalian macrophages and in infected Drosophila melanogaster, which led in turn to accelerated death of the flies. Interestingly, the fldP gene is present in some but not all P. aeruginosa strains, constituting a component of the P. aeruginosa accessory genome. It is located in a genomic island as part of a self-regulated polycistronic operon containing a suite of stress-associated genes. The collected results indicate that the fldP gene encodes a long-chain flavodoxin, which protects the cell from oxidative stress, thereby expanding the capabilities of P. aeruginosa to thrive in hostile environments. PMID:24550745

  19. Structure and Function of the Mucus Clearance System of the Lung

    PubMed Central

    Button, Brenda M.; Button, Brian

    2013-01-01

    In cystic fibrosis (CF), a defect in ion transport results in thick and dehydrated airway mucus, which is difficult to clear, making such patients prone to chronic inflammation and bacterial infections. Physiotherapy using a variety of airway clearance techniques (ACTs) represents a key treatment regime by helping clear the airways of thickened, adhered, mucus and, thus, reducing the impact of lung infections and improving lung function. This article aims to bridge the gap between our understanding of the physiological effects of mechanical stresses elicited by ACTs on airway epithelia and the reported effectiveness of ACTs in CF patients. In the first part of this review, the effects of mechanical stress on airway epithelia are discussed in relation to changes in ion transport and stimulation in airway surface layer hydration. The second half is devoted to detailing the most commonly used ACTs to stimulate the removal of mucus from the airways of patients with CF. PMID:23751214

  20. Intraarticular volume and clearance in human synovial effusions

    SciTech Connect

    Wallis, W.J.; Simkin, P.A.; Nelp, W.B.; Foster, D.M.

    1985-04-01

    Intraarticular volumes were measured by radiolabeled albumin (RISA) distribution in chronic knee effusions from 11 rheumatoid arthritis patients and 9 osteoarthritis patients. Volumes of synovial fluid obtained at joint aspiration were substantially less than those found by RISA dilution. Up to 24 hours was needed for full distribution of RISA throughout the intraarticular compartment. Measured 123I and RISA radioactivity over the knee described monoexponential rate constants, lambda (minute-1). The clearance of 123I and RISA from synovial effusions was derived by the formulation volume (ml) X lambda (minute-1) = clearance (ml/minute). RISA clearance in rheumatoid effusions was significantly greater than that found in osteoarthritis effusions. Intraarticular volume and isotope clearance were easily quantified and provide measures for further evaluating the microvascular physiology of synovial effusions.

  1. 54. CLEARANCE OF SITE PRIOR TO CONSTRUCTION OF BREAKER BUILDING, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. CLEARANCE OF SITE PRIOR TO CONSTRUCTION OF BREAKER BUILDING, AND CONSTRUCTION OF EMBANKMENT FOR RAILROAD SPUR. c.1898 (AKZO No. A-3) - Avery Island Salt Works, Akzo Salt Incorporated, Avery Island, Iberia Parish, LA

  2. [Bromsulphalein clearance in persons in occupational contact with pesticides].

    PubMed

    Mechkov, G; Petkova, V; Zakhariev, N

    1987-01-01

    In 46 persons (sprayers, disinfectors, technicians of the agricultural aviation) the bromsulphalein clearance is traced, during the active work season with pesticides, after the method of Caroly, Nys and Alliot. It is established, that the mean value of bromsulphalein clearance (8.91%) is lower than that of the referent group healthy persons (14.5%). In 14 (31.34%) of the examined the values of the clearance are under 10%. The changes of the last do not correlate closely to other indices of the liver function. As an explanation of the results the authors presuppose general pathogenetic relations between the metabolism of pesticides and of bromsulphalein in the liver cell, with inclusion of glutathione-S-transferase systems. The study allows to give a practical conclusion for the meaning of the bromsulphalein clearance and assessment of the pesticides effect in persons who are in professional contact with them. PMID:3441475

  3. 75 FR 37518 - Agency Information Collection Activities: Emergency Clearance Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-29

    ... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY ADMINISTRATION Agency Information Collection Activities: Emergency Clearance Request The Social Security... technology. Mail, e-mail, or fax your comments and recommendations on the information collection to the...

  4. Mucociliary clearance mechanism in smoking and nonsmoking normal subjects

    SciTech Connect

    Isawa, T.; Teshima, T.; Hirano, T.; Ebina, A.; Konno, K.

    1984-03-01

    Mucociliary clearance mechanisms were evaluated in 17 normal subjects visually and qualitatively by radioaerosol inhalation cinescintigraphy of the lung, and quantitatively by calculating the following indices: (a) overall or regional lung retention ratio; (b) airway deposition ratio; (c) airway retention ratio; (d) airway clearance efficiency; and (e) alveolar deposition ratio. The inhaled aerosol deposited homogeneously throughout the lungs, and mucus transport was always cephalad in direction and constant in velocity, although a temporary stasis of mucus was seen in smokers. Overall lung retention ratio was significantly smaller and airway deposition ratio was significantly larger in the smokers than in nonsmokers, but there was no difference between the groups in airway retention ratio or airway clearance efficiency. There was an inverse relationship between alveolar deposition ratio and cigarette consumption. Mucociliary clearance mechanisms were well maintained in the normal subjects, but in the smokers inhaled aerosol tended to deposit more proximally.

  5. 33 CFR 151.1508 - Revocation of clearance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in the Great Lakes and Hudson River § 151.1508 Revocation of clearance. A COTP may request the District Director of Customs...

  6. 33 CFR 151.1508 - Revocation of clearance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in the Great Lakes and Hudson River § 151.1508 Revocation of clearance. A COTP may request the District Director of Customs...

  7. 33 CFR 151.1508 - Revocation of clearance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in the Great Lakes and Hudson River § 151.1508 Revocation of clearance. A COTP may request the District Director of Customs...

  8. Further Characterization of an Active Clearance Control Concept

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn C.; Steinetz, Bruce M.; Oswald, Jay J.

    2007-01-01

    A new test chamber and precision hydraulic actuation system were incorporated into an active clearance control (ACC) test rig at NASA Glenn Research Center. Using the improved system, a fast-acting, mechanically-actuated, ACC concept was evaluated at engine simulated temperatures and pressure differentials up to 1140 F and 120 psig, on the basis of secondary seal leakage and kinematic controllability. During testing, the ACC concept tracked a simulated flight clearance transient profile at 1140 F, 120 psig, with a maximum error of only 0.0012 in. Comparison of average dynamic leakage of the system with average static leakage did not show significant differences between the two operating conditions. Calculated effective clearance values for the rig were approximately 0.0002 in. at 120 psig, well below the industry specified effective clearance threshold of 0.001 in.

  9. 32 CFR 644.517 - Clearance of Army lands.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Clearance, the following information will be furnished to the DE upon completion of the neutralization: (a) Records of the neutralization work performed, including statement of methods employed. (b) List...

  10. 32 CFR 644.517 - Clearance of Army lands.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Clearance, the following information will be furnished to the DE upon completion of the neutralization: (a) Records of the neutralization work performed, including statement of methods employed. (b) List...

  11. 32 CFR 644.517 - Clearance of Army lands.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Clearance, the following information will be furnished to the DE upon completion of the neutralization: (a) Records of the neutralization work performed, including statement of methods employed. (b) List...

  12. 32 CFR 644.517 - Clearance of Army lands.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Clearance, the following information will be furnished to the DE upon completion of the neutralization: (a) Records of the neutralization work performed, including statement of methods employed. (b) List...

  13. 32 CFR 644.517 - Clearance of Army lands.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Clearance, the following information will be furnished to the DE upon completion of the neutralization: (a) Records of the neutralization work performed, including statement of methods employed. (b) List...

  14. IFNL4 affects clearance of hepatitis C virus

    Cancer.gov

    Scientists have discovered a new human interferon gene, Interferon Lambda 4 (IFNL4), that affects clearance of the hepatitis C virus. They also identified an inherited genetic variant within IFNL4 that predicts how people respond to treatment for hepatit

  15. Clearance detector and method for motion and distance

    DOEpatents

    Xavier, Patrick G.

    2011-08-09

    A method for correct and efficient detection of clearances between three-dimensional bodies in computer-based simulations, where one or both of the volumes is subject to translation and/or rotations. The method conservatively determines of the size of such clearances and whether there is a collision between the bodies. Given two bodies, each of which is undergoing separate motions, the method utilizes bounding-volume hierarchy representations for the two bodies and, mappings and inverse mappings for the motions of the two bodies. The method uses the representations, mappings and direction vectors to determine the directionally furthest locations of points on the convex hulls of the volumes virtually swept by the bodies and hence the clearance between the bodies, without having to calculate the convex hulls of the bodies. The method includes clearance detection for bodies comprising convex geometrical primitives and more specific techniques for bodies comprising convex polyhedra.

  16. Numerical simulation of tip clearance effects in turbomachinery

    SciTech Connect

    Basson, A.; Lakshminarayana, B.

    1995-07-01

    The numerical formulation developed here includes an efficient grid generation scheme, particularly suited to computational grids for the analysis of turbulent turbomachinery flows and tip clearance flows, and a semi-implicit, pressure-based computational fluid dynamics scheme that directly includes artificial dissipation,a nd is applicable to both viscous and inviscid flows. The value of this artificial dissipation is optimized to achieve accuracy and convergency in the solution. The numerical model is used to investigate the structure of tip clearance flows in a turbine nozzle. The structure of leakage flow is captured accurately, including blade-to-blade variation of all three velocity components, pitch and yaw angles, losses and blade static pressures in the tip clearance region. The simulation also includes evaluation of such quantities the spanwise extent affected by the leakage flow. It is demonstrated, through optimization of grid size and artificial dissipation, that the tip clearance flow field can be captured accurately.

  17. Antibody-Mediated Clearance of Alphavirus Infection from Neurons

    NASA Astrophysics Data System (ADS)

    Levine, Beth; Hardwick, J. Marie; Trapp, Bruce D.; Crawford, Thomas O.; Bollinger, Robert C.; Griffin, Diane E.

    1991-11-01

    Humoral immunity is important for protection against viral infection and neutralization of extracellular virus, but clearance of virus from infected tissues is thought to be mediated solely by cellular immunity. However, in a SCID mouse model of persistent alphavirus encephalomyelitis, adoptive transfer of hyperimmune serum resulted in clearance of infectious virus and viral RNA from the nervous system, whereas adoptive transfer of sensitized T lymphocytes had no effect on viral replication. Three monoclonal antibodies to two different epitopes on the E2 envelope glycoprotein mediated viral clearance. Treatment of alphavirus-infected primary cultured rat neurons with these monoclonal antibodies to E2 resulted in decreased viral protein synthesis, followed by gradual termination of mature infectious virion production. Thus, antibody can mediate clearance of alphavirus infection from neurons by restricting viral gene expression.

  18. High Temperature Evaluation of an Active Clearance Control System Concept

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn C.; Steinetz, Bruce M.; Oswald, Jay J.

    2006-01-01

    A mechanically actuated blade tip clearance control concept was evaluated in a nonrotating test rig to quantify secondary seal leakage at elevated temperatures. These tests were conducted to further investigate the feasibility of actively controlling the clearance between the rotor blade tips and the surrounding shroud seal in the high pressure turbine (HPT) section of a turbine engine. The test environment simulates the state of the back side of the HPT shroud seal with pressure differentials as high as 120 psig and temperatures up to 1000 F. As expected, static secondary seal leakage decreased with increasing temperature. At 1000 F, the test rig's calculated effective clearance (at 120 psig test pressure) was 0.0003 in., well within the industry specified effective clearance goal.

  19. Radioaerosol clearance to monitor effects of ozone on lung permeability

    SciTech Connect

    Webb, D.A.; Utell, M.J.; Bauer, M.A.; Banko, T.M.; Waldman, D.L.; Morrow, P.E.; Hyde, R.W.

    1985-05-01

    The Tc-99m DTPA aerosol clearance procedure was used to investigate the effects of low level ozone inhalation on lung permeability. Total and regional lung clearance was determined by scintillation camera imaging of 15 adult subjects presenting no history of lung disease using a radioaerosol with an aerodynamic diameter 0.5 ..mu..m(sigmag=1.50). Pulmonary function measurements and the radioaerosol procedure were conducted in each patient on at least two separate occasions. FVC, FEVl and airway resistance was measured pre and post monitored breathing of room air (30 min) and a subsequent aerosol clearance procedure was conducted as a baseline study; the same procedures were repeated after three or more days with 0.5 ppm ozone substituted for room air. The major observations from the clearance studies and the pulmonary function tests include: 1) no significant changes were detected between the baseline and ozone pulmonary function tests, 2) ROI analyses of the 30 min clearance data show no significant changes in the average Tc-99m DTPA clearance between the baseline room air (t1/2=85+-30 min) and ozone (t1/2=83+-24min) inhalation studies, and, 3) despite consistent average clearance rates, 7/15 subjects showed large changes in clearance (..delta..=24-72 min) and functional mapping showed major shifts in distribution in 5/15 subjects after ozone inhalation. The apparent high sensitivity, yet somewhat disparate observations, support the need of further investigation of factors influencing radioaerosol for the study of lung epithelial permeability.

  20. Measuring Motor-Shaft Clearance And Wobble During Operation

    NASA Technical Reports Server (NTRS)

    Chern, Engmin James

    1996-01-01

    Noncontact proximity sensor, preferably eddy-current liftoff probe, provides realtime measurement of distance and small variations of distance between two mechanical components designed to be maintained at precise, fixed distance. In particular, system intended for use in measuring lateral clearance and variations in lateral clearance (wobble) of motor shaft relative to motor housing while shaft turning. Provides early indication of wear in motor bearings. Rate of rotation also measured.

  1. Early Agriculture: Land Clearance and Climate Effects

    NASA Astrophysics Data System (ADS)

    Ruddiman, W. F.

    2013-12-01

    inception. Well-dated high-resolution CO2 (and CH4) records from ice cores show gas decreases that correlate closely with major pandemics and civil strife, but show little if any link to temperature or precipitation trends. One significant (and intriguing) discrepancy with the original hypothesis remains. Most of the CO2 rise occurred between 6000 and 2500 years ago, well before the major increase in global population that has been hindcast from geometric models that assume a constant fractional rate of population increase. Some of this discrepancy has been reconciled by historical evidence showing much higher per-capita clearance millennia ago than later in pre-industrial time, resulting in disproportionately large early clearance and CO2 emissions. In addition, DNA studies and archeological syntheses now indicate that early farming populations initially grew at very fast rates favored by environments rich in basic resources (especially fertile soils), but then slowed in later millennia because of growing resource limitations and the effects of pandemics and civil strife in checking population growth. This emerging view of fast-rising early population trends has the potential to account for the early timing of the CO2 increase.

  2. Cell-phone use diminishes self-awareness of impaired driving.

    PubMed

    Sanbonmatsu, David M; Strayer, David L; Biondi, Francesco; Behrends, Arwen A; Moore, Shannon M

    2016-04-01

    Multitasking diminishes the self-awareness of performance that is often essential for self-regulation and self-knowledge. Participants drove in a simulator while either talking or not talking on a hands-free cell phone. Following previous research, participants who talked on a cell phone made more serious driving errors than control participants who did not use a phone while driving. Control participants' assessments of the safeness of their driving and general ability to drive safely while distracted were negatively correlated with the actual number of errors made when they were driving. By contrast, cell-phone participants' assessments of the safeness of their driving and confidence in their driving abilities were uncorrelated with their actual errors. Thus, talking on a cell phone not only diminished the safeness of participants' driving, it diminished their awareness of the safeness of their driving. PMID:26282831

  3. Neutrophil depletion causes a fatal defect in murine pulmonary Staphylococcus aureus clearance

    PubMed Central

    Robertson, Charles M.; Perrone, Erin E; McConnell, Kevin W.; Dunne, W. Michael; Boody, Barrett; Brahmbhatt, Tejal; Diacovo, M. Julia; Van Rooijen, Nico; Hogue, Lisa A.; Cannon, Carolyn L.; Buchman, Timothy G.; Hotchkiss, Richard S.; Coopersmith, Craig M.

    2008-01-01

    Background Staphylococcus aureus is the most common cause of healthcare-associated pneumonia. Despite the significant morbidity and mortality associated with the disease, animal models of S. aureus pneumonia are rare. Materials and Methods We examined the pathogenicity of four different strains of S. aureus (both methicillin-sensitive and resistant as well as Panton-Valentine leukocidin positive and negative) in four strains of immunocompetent inbred and outbred mice (FVB/N, C57Bl/6, Balb/c, ND4, n=148). The immunologic basis for the development of murine S. aureus pneumonia was then determined by selectively depleting neutrophils, lymphocytes, or pulmonary macrophages prior to the onset of infection. An additional cohort of animals was rendered immunosuppressed by induction of abdominal sepsis via cecal ligation and puncture 2, 4 or 7 days prior to the onset of pneumonia. Results Nearly all immunocompetent mice survived, regardless of which strain of S. aureus was used or which strain of mouse was infected. Among animals with immune depletion or prior immunosuppression, survival was decreased only following neutrophil depletion (26% vs. 90% alive at 7 days, p<0.0001). Compared to immunocompetent animals, neutrophil-depleted mice with S. aureus pneumonia had delayed pulmonary bacterial clearance at 16 and 40 hours but had no difference in levels of bacteremia. Neutrophil-depleted mice also had elevated levels of pulmonary MCP-1 (822 pg/ml vs. 150 pg/ml, p<0.05). In contrast, pulmonary histologic appearance was similar in both groups as was dry/wet lung weight. Conclusions These results suggest that neutrophils play a critical role in the host response to S. aureus pneumonia, and the survival differences observed in neutrophil-depleted mice are associated with alterations in bacterial clearance and pulmonary cytokine response. PMID:18621398

  4. Control of influenza infection is impaired by diminished interferon-γ secretion by CD4 T cells in the lungs of toddler mice.

    PubMed

    Verhoeven, David; Perry, Sheldon; Pryharski, Karin

    2016-07-01

    Respiratory viral infections, such as influenza, can lead to delayed viral clearance in toddlers, possibly exacerbating disease morbidity. We hypothesized that defective CD4 T cells in toddlers may contribute to a failure to clear virus at a similar rate to adults. Thus, we developed a young mouse model to examine potential divergent responses between toddlers and adults. We determined that young mice (toddler mice, 21 d old) were actively generating and recruiting effector/memory T cells, whereas memory populations were firmly established in older, adult mice (8-10 wk old). We infected toddler and adult mice with influenza A/PR8/34 (H1N1) and found young mice had elevated morbidity, as measured by enhanced weight loss and lower partial pressure of oxygen levels, throughout the infection, thus, modeling the higher morbidity observed in children (<2 y old) during infection. Early viral loads were comparable to adult mice, but toddler mice failed to clear virus by 10 d postinfection. This delayed clearance corresponded to poor lung recruitment of CD4 T cells, lower antiviral T cell responses, and lower B cell/antibodies in the lungs. Mechanistically, diminished interferon-γ was detected in the lungs of toddler mice throughout the infection and corresponded to intrinsic, rather than extrinsic, CD4 T cell limitations in interferon-γ transcription. Moreover, defects in interferon-γ production appeared downstream from signal transducer and activator of transcription 4 in the interleukin-12 signaling pathway, suggesting maturational delays different from neonates. Importantly, recombinant interferon-γ supplementation rescued CD4 T cell numbers in the lungs and influenza-specific antibody formation. This study highlights the intrinsic limitations in CD4 T cell effector functions that may arise in toddlers and contribute to disease pathology. PMID:26823488

  5. A high sensitivity inductive sensor for blade tip clearance measurement

    NASA Astrophysics Data System (ADS)

    Du, Li; Zhu, Xiaoliang; Zhe, Jiang

    2014-06-01

    A multiplexed inductive sensor consisting of multiple mini-sized planar spiral coils for detecting multiple tip clearances of rotor blades is presented. The sensor measures the tip clearances by monitoring the inductance changes of planar spiral coils caused by the passage of the rotor blades. A resonance frequency division multiplexing technique and parallel LC resonance measurement were applied to the multiple sensor coils, making it feasible to measure multiple tip clearances using only one set of measurement electronics with high sensitivity and resolution. The results from tests conducted on a bench-top test rig have demonstrated that the sensor is capable of simultaneously measuring multiple tip clearances from 0 to 5 mm with a 10 μm resolution at a high rotary speed up to 80 000 RPM. With its high resolution, high sensitivity and capability of monitoring a large number of tip clearances simultaneously, this sensor can potentially be used for advanced active tip clearance control in turbine machinery.

  6. Calculation of Tip Clearance Effects in a Transonic Compressor Rotor

    NASA Technical Reports Server (NTRS)

    Chima, R. V.

    1998-01-01

    The flow through the tip clearance region of a transonic compressor rotor (NASA rotor 37) was computed and compared to aerodynamic probe and laser anemometer data. Tip clearance effects were modeled both by gridding the clearance gap and by using a simple periodicity model across the ungridded gap. The simple model was run with both the full gap height, and with half the gap height to simulate a vena-contracta effect. Comparisons between computed and measured performance maps and downstream profiles were used to validate the models and to assess the effects of gap height on the simple clearance model. Recommendations were made concern- ing the use of the simple clearance model Detailed comparisons were made between the gridded clearance gap solution and the laser anemometer data near the tip at two operating points. The computed results agreed fairly well with the data but overpredicted the extent of the casing separation and underpredicted the wake decay rate. The computations were then used to describe the interaction of the tip vortex, the passage shock, and the casing boundary layer.

  7. Calculation of tip clearance effects in a transonic compressor rotor

    NASA Technical Reports Server (NTRS)

    Chima, R. V.

    1996-01-01

    The flow through the tip clearance region of a transonic compressor rotor (NASA rotor 37) was computed and compared to aerodynamic probe and laser anemometer data. Tip clearance effects were modeled both by gridding the clearance gap and by using a simple periodicity model across the ungridded gap. The simple model was run with both the full gap height, and with half the gap height to simulate a vena-contracta effect. Comparisons between computed and measured performance maps and downstream profiles were used to validate the models and to assess the effects of gap height on the simple clearance model. Recommendations were made concerning the use of the simple clearance model. Detailed comparisons were made between the gridded clearance gap solution and the laser anemometer data near the tip at two operating points. The computer results agreed fairly well with the data but overpredicted the extent of the casing separation and underpredicted the wake decay rate. The computations were then used to describe the interaction of the tip vortex, the passage shock, and the casing boundary layer.

  8. Allometric scaling for predicting human clearance of bisphenol A.

    PubMed

    Collet, Séverine H; Picard-Hagen, Nicole; Lacroix, Marlène Z; Puel, Sylvie; Viguié, Catherine; Bousquet-Melou, Alain; Toutain, Pierre-Louis; Gayrard, Véronique

    2015-05-01

    The investigation of interspecies differences in bisphenol A (BPA) pharmacokinetics (PK) may be useful for translating findings from animal studies to humans, identifying major processes involved in BPA clearance mechanisms, and predicting BPA PK parameters in man. For the first time, a large range of species in terms of body weight, from 0.02 kg (mice) to 495 kg (horses) was used to predict BPA clearance in man by an allometric approach. BPA PK was evaluated after intravenous administration of BPA in horses, sheep, pigs, dogs, rats and mice. A non-compartmental analysis was used to estimate plasma clearance and steady state volume of distribution and predict BPA PK parameters in humans from allometric scaling. In all the species investigated, BPA plasma clearance was high and of the same order of magnitude as their respective hepatic blood flow. By an allometric scaling, the human clearance was estimated to be 1.79 L/min (equivalent to 25.6 mL/kg.min) with a 95% prediction interval of 0.36 to 8.83 L/min. Our results support the hypothesis that there are highly efficient and hepatic mechanisms of BPA clearance in man. PMID:25759244

  9. Urinary and metabolic clearances of arginine vasopressin in normal subjects

    SciTech Connect

    Moses, A.M.; Steciak, E.

    1986-08-01

    Synthetic arginine vasopressin (AVP) was infused into 11 hydrated normal subjects at five different infusion rates ranging from 10 to 350 U kg min . Each infusion rate was continued for 1 h, and urinary determinations were made on the 30- to 60-min specimens during which time there was no further rise in plasma AVP. Urinary AVP concentrations ( U/ml) and excretion rates ( U/min) increased linearly with increasing infusion rates, and the concentration of AVP in urine increased 120 times more rapid than plasma. Urinary and metabolic clearances of AVP also increased linearly with the maximum urinary clearance being 60.6% of the creatinine clearance. The total metabolic clearance of AVP (including urinary clearance) was 17.8 times that of the urinary clearance of AVP alone. These data clarify the relationships between plasma and urinary AVP in normal hydrated subjects during AVP infusion under steady-state conditions and emphasize the potential advantage of measuring urinary AVP as a monitor of endogenous AVP secretion. AVP was measured by radioimmunoassay.

  10. Model of mucociliary clearance in cystic fibrosis lungs.

    PubMed

    Kurbatova, P; Bessonov, N; Volpert, V; Tiddens, H A W M; Cornu, C; Nony, P; Caudri, D

    2015-05-01

    Mucus clearance is a primary innate defense mechanism in the human airways. Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CF is characterized by dehydration of airway surface liquid and impaired mucociliary clearance. As a result, microorganisms are not efficiently removed from the airways, and patients experience chronic pulmonary infections and inflammation. We propose a new physiologically based mathematical model of muco-ciliary transport consisting of the two major components of the mucociliary clearance system: (i) periciliary liquid layer (PCL) and (ii) mucus layer. We study mucus clearance under normal conditions and in CF patients. Restoring impaired clearance of airway secretions in one of the major goals of therapy in patients with CF. We consider the action of the aerosolized and inhaled medication dornase alfa, which reduces the viscosity of cystic fibrosis mucus, by selectively cleaving the long DNA strands it contains. The results of the model simulations stress the potential relevance of the location of the drug deposition in the central or peripheral airways. Mucus clearance was increased in case the drug was primarily deposited peripherally, i.e. in the small airways. PMID:25746843

  11. 48 CFR 245.7001-4 - DD Form 1640, Request for Plant Clearance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Plant Clearance. 245.7001-4 Section 245.7001-4 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT GOVERNMENT PROPERTY Plant Clearance Forms 245.7001-4 DD Form 1640, Request for Plant Clearance. Use to request plant clearance assistance...

  12. 48 CFR 245.7101-4 - DD Form 1640, Request for Plant Clearance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Plant Clearance. 245.7101-4 Section 245.7101-4 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT GOVERNMENT PROPERTY Plant Clearance Forms 245.7101-4 DD Form 1640, Request for Plant Clearance. Use to request plant clearance assistance...

  13. A new insight into phagocytosis of apoptotic cells: proteolytic enzymes divert the recognition and clearance of polymorphonuclear leukocytes by macrophages.

    PubMed

    Guzik, K; Bzowska, M; Smagur, J; Krupa, O; Sieprawska, M; Travis, J; Potempa, J

    2007-01-01

    The recognition of phosphatidylserine (PS) on the surface of any apoptotic cell is considered to be a key event for its clearance. We challenge this concept by showing that pretreatment of neutrophils with either host or bacterial protease affects their uptake by human monocyte-derived macrophages without having an effect on cell-surface PS presentation. Specifically, whereas preincubation of apoptotic neutrophils with cathepsin G or thrombin significantly inhibited their uptake, gingipains R or clostripain enhanced phagocytosis by macrophages. Moreover, bacterial proteinases sensitized healthy neutrophils for uptake by macrophages, whereas endogenous proteinases were unable to elicit this effect. This stimulation was apparently owing to the combined effect of proteolytic cleavage of an antiphagocytic signal (CD31) and the generation of a novel 'eat-me' signal on the neutrophil surface. These results argue that neutrophil recognition and phagocytosis by macrophages is mediated by a protein ligand whose proteolytic modification could affect the local inflammatory process. PMID:16628232

  14. The time-dependent clearance of virulent Treponema pallidum in susceptible and resistant strains of guinea pigs is significantly different.

    PubMed

    Wicher, V; Wicher, K; Abbruscato, F; Auger, I; Rudofsky, U

    1999-04-01

    The kinetics of clearance of Treponema pallidum spp. pallidum Nichols from skin and testes of susceptible C4-deficient (C4D) and -resistant Albany (Alb) strains of guinea pigs (gps) was evaluated using the polymerase chain reaction (PCR) and the rabbit infectivity test (RIT). For each strain there were two groups of animals, one infected with virulent T. pallidum (TP) and one control injected with heat-killed treponemes (HKTP). The kinetic studies and their statistical analysis showed that in the C4D strain the microbial clearance in both tissues was significantly slower (p < 0.005) and still incomplete at 3 months after infection. In the Alb strain the clearance was faster and apparently completed within a month. A greater permissiveness in bacterial growth in C4D compared to Alb appears to be one critical factor determining the different rate of local elimination after primary infection. In both strains there was some correlation between the severity and duration of cutaneous lesions and the local persistence of viable organisms. This correlation was not observed in testes. These studies suggest a genetic basis for the strain-specific susceptibility and resistance phenotypes in the pathogenesis of syphilis. PMID:10219257

  15. Dps promotes survival of nontypeable Haemophilus influenzae in biofilm communities in vitro and resistance to clearance in vivo

    PubMed Central

    Pang, Bing; Hong, Wenzhou; Kock, Nancy D.; Swords, W. Edward

    2012-01-01

    Nontypeable Haemophilus influenzae (NTHi) is a common airway commensal and opportunistic pathogen that persists within surface-attached biofilm communities. In this study, we tested the hypothesis that bacterial stress-responses are activated within biofilms. Transcripts for several factors associated with bacterial resistance to environmental stress were increased in biofilm cultures as compared to planktonic cultures. Among these, a homolog of the DNA-binding protein from starved cells (dps) was chosen for further study. An isogenic NTHi 86-028NP dps mutant was generated and tested for resistance to environmental stress, revealing a significant survival defects in high-iron conditions, which was mediated by oxidative stress and was restored by genetic complementation. As expected, NTHi 86-028NP dps had a general stress-response defect, exhibiting decreased resistance to many types of environmental stress. While no differences were observed in density and structure of NTHi 86-028NP and NTHi 86-028NP dps biofilms, bacterial survival was decreased in NTHi 86-028NP dps biofilms as compared to the parental strain. The role of dps persistence in vivo was tested in animal infection studies. NTHi 86-028NP dps had decreased resistance to clearance after pulmonary infection of elastase-treated mice as compared to NTHi 86-028NP, whereas minimal differences were observed in clearance from mock-treated mice. Similarly, lower numbers of NTHi 86-028NP dps were recovered from middle-ear effusions and bullar homogenates in the chinchilla model for otitis media (OM). Therefore, we conclude that Dps promotes bacterial survival within NTHi biofilm communities both in vitro and in chronic infections in vivo. PMID:22919649

  16. Rehearsal Strategies Can Enlarge or Diminish the Spacing Effect: Pure versus Mixed Lists and Encoding Strategy

    ERIC Educational Resources Information Center

    Delaney, Peter F.; Verkoeijen, Peter P. J. L.

    2009-01-01

    Using 5 experiments, the authors explored the dependency of spacing effects on rehearsal patterns. Encouraging rehearsal borrowing produced opposing effects on mixed lists (containing both spaced and massed repetitions) and pure lists (containing only one or the other), magnifying spacing effects on mixed lists but diminishing spacing effects on…

  17. Perceptions of Absenteeism and Diminished Engagement among Instructors and Nonlicensed Students in Medical Assistant Programs

    ERIC Educational Resources Information Center

    Miller, Russell

    2012-01-01

    Adult nonlicensed students can experience diminished engagement and increased absenteeism while attempting to complete medical assistant programs. The purpose of this qualitative, multisite narrative case study was to explore the perceptions, meanings, and interpretations of instructors and students. The theoretical foundation focused on the…

  18. A Test of Spearman's ''Law of Diminishing Returns'' in Two Large Samples of Danish Military Draftees

    ERIC Educational Resources Information Center

    Hartmann, Peter; Teasdale, Thomas W.

    2004-01-01

    Spearman's ''Law of Diminishing Returns'' (SLODR) predicts that "g" saturation for cognitive tests will be lower at high ability levels than at low ability levels. This hypothesis was tested in two large samples of Danish military draftees (n=33,833 and n=25,020). The subjects were representative samples of the young adult male population and 95%…

  19. Dietary long-chain omega-3 fatty acids do not diminish eosinophilic pulmonary inflammation in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of fish oil supplements on diminishing airway inflammation in asthma have been studied in mouse models and human intervention trials with varying results. However, the independent effects of the main omega-3 PUFAs found in fish oil, eicosapentaenoic acid (EPA) and docosahexaenoic acid (D...

  20. Diminishing Marginal Returns and the Production of Education: An International Analysis

    ERIC Educational Resources Information Center

    Harris, Douglas N.

    2007-01-01

    Diminishing marginal returns (DMR) to school inputs could explain a wide variety of findings in the research literature. One important example is the influential finding by Heyneman and Loxley that school inputs are the 'predominant influence' on achievement in developing nations, where input levels are low, even though the same school inputs have…

  1. DIMINISHED INJURY IN HYPOTRANSFERENEMIC MICE AFTER EXPOSURE TO A METAL-RICH PARTICLE

    EPA Science Inventory

    Using the hypotransferrinemic (Hp) mouse model, we studied the effect of altered iron homeostasis on the lung?s defense against catalytically active metal. The homozygotic (hpx/hpx) Hp mice had greatly diminished concentrations of both serum and lavage transferrin relative to ...

  2. Rural Areas in the Information Society: Diminishing Distance or Increasing Learning Capacity?

    ERIC Educational Resources Information Center

    Grimes, Seamus

    2000-01-01

    Examines prospects for rural areas within the Information Society, referring particularly to the European Union. Discusses effects of diminished distance from core markets, increased learning capacity through improved access to information, public policy emphasis on building infrastructure, disappointing outcomes for telecommunications initiatives…

  3. Can Using Human Examples Diminish the Number of Misconceptions Held Concerning Mendelian Genetics Concepts?

    ERIC Educational Resources Information Center

    Moore, John M.

    2000-01-01

    Explores high school biology and the teaching of genetics. The question is asked, Can the use of relevant, meaningful human genetics concepts diminish the number of misconceptions formed between new and existing concepts? Can the application of the Ausubelian learning theory also decrease the acquisition of misconceptions? (SAH)

  4. Direct Instruction and Music Literacy: One Approach to Augmenting the Diminishing?

    ERIC Educational Resources Information Center

    Lowe, Geoffrey; Belcher, Steven

    2012-01-01

    One of the many challenges facing music educators is diminishing class time in lower secondary school in the face of the increasingly crowded curriculum and the advent of arts "taster" courses. However, music educators are still expected to be able to produce musically literate students capable of completing high level music courses in upper…

  5. Less Guilty by Reason of Adolescence: Developmental Immaturity, Diminished Responsibility, and the Juvenile Death Penalty

    ERIC Educational Resources Information Center

    Steinberg, Laurence; Scott, Elizabeth S.

    2003-01-01

    The authors use a developmental perspective to examine questions about the criminal culpability of juveniles and the juvenile death penalty. Under principles of criminal law, culpability is mitigated when the actor's decision-making capacity is diminished, when the criminal act was coerced, or when the act was out of character. The authors argue…

  6. Epstein-Barr Virus Reactivation Associated with Diminished Cell-Mediated Immunity in Antarctic Expeditioners

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Mehta, Satish K.; Cooley, Helen; Dubow, Robin; Lugg, Desmond

    1999-01-01

    Reactivation of Epstein-Barr virus (EBV) and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at two Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity skin testing was used as an indicator of the CMI response, which was evaluated two times before winter isolation and three times during isolation. At all five evaluation times, 8 or more of the 16 subjects had a diminished. CMI response. Diminished CMI was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal CMI responses for all five tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, after, and during the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least one occasion. The probability of EBV shedding increased (p=0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (p<0.0005) when CMI responsiveness was diminished than when CMI status was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter results in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

  7. Epstein-Barr virus reactivation associated with diminished cell-mediated immunity in antarctic expeditioners

    NASA Technical Reports Server (NTRS)

    Mehta, S. K.; Pierson, D. L.; Cooley, H.; Dubow, R.; Lugg, D.

    2000-01-01

    Epstein-Barr virus (EBV) reactivation and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at 2 Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity (DTH) skin testing was used as an indicator of the CMI response, that was evaluated 2 times before winter isolation and 3 times during isolation. At all 5 evaluation times, 8 or more of the 16 subjects had a diminished CMI response. Diminished DTH was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal DTH responses for all 5 tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, during, and after the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least 1 occasion. The probability of EBV shedding increased (P = 0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (P < 0.0005) when DTH response was diminished than when DTH was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter result in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

  8. Challenging the Presumption of Diminished Capacity to Parent: Does Divorce Really Change Parenting Practices?

    ERIC Educational Resources Information Center

    Strohschein, Lisa

    2007-01-01

    The purpose of this paper is to determine whether divorced parents exhibit a diminished capacity to parent in the period following divorce. Using 2 waves of data from a national survey of Canadian children, the current study prospectively follows 5,004 children living in 2-biological parent households at initial interview and compares changes in…

  9. Altered intramuscular lipid metabolism relates to diminished insulin action in men, but not women, in progression to diabetes.

    PubMed

    Perreault, Leigh; Bergman, Bryan C; Hunerdosse, Devon M; Eckel, Robert H

    2010-11-01

    Whether sex differences in intramuscular triglyceride (IMTG) metabolism underlie sex differences in the progression to diabetes are unknown. Therefore, the current study examined IMTG concentration and fractional synthesis rate (FSR) in obese men and women with normal glucose tolerance (NGT) vs. those with prediabetes (PD). PD (n = 13 men and 7 women) and NGT (n = 7 men and 12 women) groups were matched for age and anthropometry. Insulin action was quantified using a hyperinsulinemic-euglycemic clamp with infusion of [6,6-(2)H(2)]-glucose. IMTG concentration was measured by gas chromatography/mass spectrometry (GC/MS) and FSR by GC/combustion isotope ratio MS (C-IRMS), from muscle biopsies taken after infusion of [U-(13)C]palmitate during 4 h of rest. In PD men, the metabolic clearance rate (MCR) of glucose was lower during the clamp (4.71 ± 0.77 vs. 8.62 ± 1.26 ml/kg fat-free mass (FFM)/min, P = 0.04; with a trend for lower glucose rate of disappearance (Rd), P = 0.07), in addition to higher IMTG concentration (41.2 ± 5.0 vs. 21.2 ± 3.4 µg/mg dry weight, P ≤ 0.01), lower FSR (0.21 ± 0.03 vs. 0.42 ± 0.06 %/h, P ≤ 0.01), and lower oxidative capacity (P = 0.03) compared to NGT men. In contrast, no difference in Rd, IMTG concentration, or FSR was seen in PD vs. NGT women. Surprisingly, glucose Rd during the clamp was not different between NGT men and women (P = 0.25) despite IMTG concentration being higher (42.6 ± 6.1 vs. 21.2 ± 3.4 µg/mg dry weight, P = 0.03) and FSR being lower (0.23 ± 0.04 vs. 0.42 ± 0.06 %/h, P = 0.02) in women. Alterations in IMTG metabolism relate to diminished insulin action in men, but not women, in the progression toward diabetes. PMID:20379150

  10. Recurrent osteomyelitis caused by infection with different bacterial strains without obvious source of reinfection.

    PubMed

    Uçkay, Ilker; Assal, Mathieu; Legout, Laurence; Rohner, Peter; Stern, Richard; Lew, Daniel; Hoffmeyer, Pierre; Bernard, Louis

    2006-03-01

    Recurrence of osteomyelitis by the same bacterial strain is well known. We report three patients with a second episode of osteomyelitis at the same site caused by different strains of bacteria from the original. Formerly infected and altered bone surface might present a region of diminished resistance for a new infection. PMID:16517930

  11. Recurrent Osteomyelitis Caused by Infection with Different Bacterial Strains without Obvious Source of Reinfection

    PubMed Central

    Uçkay, Ilker; Assal, Mathieu; Legout, Laurence; Rohner, Peter; Stern, Richard; Lew, Daniel; Hoffmeyer, Pierre; Bernard, Louis

    2006-01-01

    Recurrence of osteomyelitis by the same bacterial strain is well known. We report three patients with a second episode of osteomyelitis at the same site caused by different strains of bacteria from the original. Formerly infected and altered bone surface might present a region of diminished resistance for a new infection. PMID:16517930

  12. Bacterial concentration and diversity within repetitive aliquots collected from replicate continuous flow bioreactor cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: The aims of this study were to determine if: 1) aqueous and biofilm components within replicate, stabilized bioreactor communities initiated with chicken cecal material differed in diversity; 2) changes in bacterial diversity or diminished protective capabilities resulted from frozen glycerol ...

  13. Clearance mechanism assignment and total clearance prediction in human based upon in silico models.

    PubMed

    Lombardo, Franco; Obach, R Scott; Varma, Manthena V; Stringer, Rowan; Berellini, Giuliano

    2014-05-22

    We introduce a two-tier model based on an exhaustive data set, where discriminant models based on principal component analysis (PCA) and partial least squares (PLS) are used separately and in conjunction, and we show that PCA is highly discriminant approaching 95% accuracy in the assignment of the primary clearance mechanism. Furthermore, the PLS model achieved a quantitative predictive performance comparable to methods based on scaling of animal data while not requiring the use of either in vivo or in vitro data, thus sparing the use of animal. This is likely the highest performance that can be expected from a computational approach, and further improvements may be difficult to reach. We further offer the medicinal scientist a PCA model to guide in vitro and/or in vivo studies to help limit the use of resources via very rapid computations. PMID:24773013

  14. Relationships between periodontal disease and bacterial pneumonia.

    PubMed

    Scannapieco, F A; Mylotte, J M

    1996-10-01

    Bacterial pneumonia is a prevalent and costly infection that is a significant cause of morbidity and mortality in patients of all ages. The continuing emergence of antibiotic-resistant bacteria (e.g., penicillin-resistant pneumococci) suggests that bacterial pneumonia will assume increasing importance in the coming years. Thus, knowledge of the pathogenesis of, and risk factors for, bacterial pneumonia is critical to the development of strategies for prevention and treatment of these infections. Bacterial pneumonia in adults is the result of aspiration of oropharyngeal flora into the lower respiratory tract and failure of host defense mechanisms to eliminate the contaminating bacteria, which multiply in the lung and cause infection. It is recognized that community-acquired pneumonia and lung abscesses can be the result of infection by anaerobic bacteria; dental plaque would seem to be a logical source of these bacteria, especially in patients with periodontal disease. It is also possible that patients with high risk for pneumonia, such as hospitalized patients and nursing home residents, are likely to pay less attention to personal hygiene than healthy patients. One important dimension of this personal neglect may be diminished attention to oral hygiene. Poor oral hygiene and periodontal disease may promote oropharyngeal colonization by potential respiratory pathogens (PRPs) including Enterobacteriaceae (Klebsiella pneumoniae, Escherichia coli, Enterobacter species, etc.), Pseudomonas aeruginosa, and Staphylococcus aureus. This paper provides the rationale for the development of this hypothesis especially as it pertains to mechanically ventilated intensive care unit patients and nursing home residents, two patient groups with a high risk for bacterial pneumonia. PMID:8910830

  15. Salivary clearance of sugar and its effects on pH changes by Streptococcus mitior in an artificial mouth.

    PubMed

    Lagerlöf, F; Dawes, R; Dawes, C

    1984-11-01

    We recently developed a computer model of oral sugar clearance (Dawes, 1983), and an artificial mouth has now been constructed which will allow variation in the salivary parameters identified in the model and the study of their effects on bacterial acid production. Using a thin layer of S. mitior, strain 572, over a miniature Sb electrode to measure bacterial pH changes during sugar clearance from the "mouth", we found that three consecutive sets of "Stephan curves" could be obtained with the same bacteria during one day. In each of several experimental series, one salivary parameter was varied, while other parameters were held constant. The maximum pH decrease and the surface area of the registered Stephan curve (delta pH.min) were used as measures of acid production. The results indicate that the volume of "saliva" in the mouth before and after swallowing, the unstimulated salivary flow rate, and the buffer capacity had significant influences on the extent of the pH changes. Other factors, such as the maximum flow rate, the delay between start of stimulation and maximum flow, the volume of saliva in the mouth at time zero, and the taste threshold for sugar, were of lesser importance, confirming some predictions from the computer model. PMID:6594367

  16. Influence of chronic amphetamine treatment and acute withdrawal on serotonin synthesis and clearance mechanisms in the rat ventral hippocampus.

    PubMed

    Barr, Jeffrey L; Scholl, Jamie L; Solanki, Rajeshwari R; Watt, Michael J; Lowry, Christopher A; Renner, Kenneth J; Forster, Gina L

    2013-02-01

    Amphetamine withdrawal in both humans and rats is associated with increased anxiety states, which are thought to contribute to drug relapse. Serotonin in the ventral hippocampus mediates affective behaviors, and reduced serotonin levels in this region are observed in rat models of high anxiety, including during withdrawal from chronic amphetamine. This goal of this study was to understand the mechanisms by which reduced ventral hippocampus serotonergic neurotransmission occurs during amphetamine withdrawal. Serotonin synthesis (assessed by accumulation of serotonin precursor as a measure of the capacity of in vivo tryptophan hydroxylase activity), expression of serotonergic transporters, and in vivo serotonergic clearance using in vivo microdialysis were assessed in the ventral hippocampus in adult male Sprague Dawley rats at 24 h withdrawal from chronic amphetamine. Overall, results showed that diminished extracellular serotonin at 24 h withdrawal from chronic amphetamine was not accompanied by a change in capacity for serotonin synthesis (in vivo tryptophan hydroxylase activity), or serotonin transporter expression or function in the ventral hippocampus, but instead was associated with increased expression and function of organic cation transporters (low-affinity, high-capacity serotonin transporters). These findings suggest that 24 h withdrawal from chronic amphetamine reduces the availability of extracellular serotonin in the ventral hippocampus by increasing organic cation transporter-mediated serotonin clearance, which may represent a future pharmacological target for reversing anxiety states during drug withdrawal. PMID:23157166

  17. Inhibition of Astrocytic Glutamine Synthetase by Lead is Associated with a Slowed Clearance of Hydrogen Peroxide by the Glutathione System

    PubMed Central

    Robinson, Stephen R.; Lee, Alan; Bishop, Glenda M.; Czerwinska, Hania; Dringen, Ralf

    2015-01-01

    Lead intoxication in humans is characterized by cognitive impairments, particularly in the domain of memory, where evidence indicates that glutamatergic neurotransmission may be impacted. Animal and cell culture studies have shown that lead decreases the expression and activity of glutamine synthetase (GS) in astrocytes, yet the basis of this effect is uncertain. To investigate the mechanism responsible, the present study exposed primary astrocyte cultures to a range of concentrations of lead acetate (0–330 μM) for up to 24 h. GS activity was significantly reduced in cells following 24 h incubation with 100 or 330 μM lead acetate. However, no reduction in GS activity was detected when astrocytic lysates were co-incubated with lead acetate, suggesting that the mechanism is not due to a direct interaction and involves intact cells. Since GS is highly sensitive to oxidative stress, the capacity of lead to inhibit the clearance of hydrogen peroxide (H2O2) was investigated. It was found that exposure to lead significantly diminished the capacity of astrocytes to degrade H2O2, and that this was due to a reduction in the effectiveness of the glutathione system, rather than to catalase. These results suggest that the inhibition of GS activity in lead poisoning is a consequence of slowed H2O2 clearance, and supports the glutathione pathway as a primary therapeutic target. PMID:26696846

  18. Pulmonary function and clearance after prolonged sulfuric acid aerosol exposure

    SciTech Connect

    Ives, P.J. ); Gerrity, T.R.; DeWitt, P.; Folinsbee, L.J. )

    1991-03-15

    The authors studied pulmonary function and clearance responses after a 4 H exposure to 75-100 {mu}g/m{sup 3} sulfuric acid aerosol (SAA). Healthy subjects, who exercised for 30 min/H at ventilation of about 25 L/min, were exposed once to clean air and once to SAA. Oral hygiene and acidic juice gargle were used to minimize oral ammonia. Lung function tests, including spirometry, plethysmography, and partial flow-volume (PEFV) curves were performed before and after exposure. Clearance of 99m-Technetium labeled iron oxide was assessed after each exposure. The first moment of fractional tracheobronchial retention (M1TBR), after correcting for 24 H retention and normalizing to time zero, was used as an index of clearance. There were no significant changes in lung volumes, airways resistance, or maximum expiratory flows after SAA exposure. Flow at 40% of total lung capacity on PEFV curves decreased 17% (NS) after SAA exposure. Tracheobronchial clearance was accelerated after a single exposure to SAA; M1TBR decreased from 73 {plus minus} 5 min (air) to 69 {plus minus} 5 min (SAA). These results suggest that acute prolonged exposure to low levels of SAA has minimal effects on lung mechanics in healthy subjects but does produce a modest acceleration of particle clearance.

  19. Experimental and Numerical Study on Blanking Process with Negative Clearance

    NASA Astrophysics Data System (ADS)

    Hirota, Kenji; Yanaga, Hiroki; Fukushima, Katsunori

    This study summarizes the characteristics of blanking behavior with a negative clearance. Several experiments were performed for two aluminum sheets over a wide range of clearances including negative values. Blanking with negatively large clearances was found to produce fine cut edges with less roll-over and no fracture zone even for a brittle material. Corresponding simulations were performed using the Ayada's criterion for predicting ductile fracture initiation. Each zone of blanked part edges such as roll-over and fractured zone agreed well with that obtained in the experiments except a few cases accompanied by secondary shear. The reason for prevention of fracture by using negative clearances was explained with the change of the damage value during the process; the damage value was kept low throughout the blanking operation since the mean stress dominating the damage value became compressive around the die edge. Influences of blanking parameters on load-stroke curves were also investigated. The curves for negative clearances showed gradual increase in load toward the end of stroke. The earlier fracture initiated, the earlier the load reached a peak. Simulated curves showed the same tendency and in good agreement with the experimental ones quantitatively.

  20. ELMO1 signaling in apoptotic germ cell clearance and spermatogenesis.

    PubMed

    Elliott, Michael R; Ravichandran, Kodi S

    2010-10-01

    Apoptosis and the subsequent removal of dying cells are crucial processes for tissue development and maintenance. Although we are beginning to understand the signaling pathways that control the phagocytic clearance of apoptotic cells, the physiological relevance of these pathways is lacking. During spermatogenesis, over half of the developing germ cells eventually die by apoptosis, yet the signaling pathways that regulate the phagocytic clearance of these dying cells or the impact of this clearance on development and maintenance of the germ cell population is not well understood. The ELMO1/Dock180 proteins form an evolutionarily conserved signaling module that functions as a bipartite guanine nucleotide exchange factor for the small GTPase Rac. The subsequent Rac-dependent cytoskeletal changes play an important role in the physical engulfment of apoptotic cells. Recent findings demonstrate an in vivo role for ELMO1-dependent clearance in the testes, with implications for spermatogenesis. Here we will discuss the role of apoptotic cell clearance during spermatogenesis, with a particular emphasis on ELMO1/Dock180 signaling. PMID:20958313

  1. Renal Clearance and Degradation of Glutathione-Coated Copper Nanoparticles

    PubMed Central

    Yang, Shengyang; Sun, Shasha; Zhou, Chen; Hao, Guiyang; Liu, Jinbin; Ramezani, Saleh; Yu, Mengxiao; Sun, Xiankai; Zheng, Jie

    2016-01-01

    Degradation of inorganic nanoparticles (NPs) into small molecular complexes is often observed in the physiological environment; however, how this process influences renal clearance of inorganic NPs is largely unknown. By systematically comparing renal clearance of degradable luminescent glutathione coated copper NPs (GS-CuNPs) and their dissociated products, Cu(II)-glutathione disulfide (GSSG) complexes (Cu(II)-GSSG), we found that GS-CuNPs were eliminated through the urinary system surprisingly faster and accumulated in the liver much less than their smaller dissociation counterparts. With assistance of radiochemistry and positron emission tomography (PET) imaging, we found that the observed “nano size” effect in enhancing renal clearance is attributed to the fact that GS-CuNPs are more resistant to serum protein adsorption than Cu(II)-GSSG. In addition, since dissociation of GS-CuNPs follows zero-order chemical kinetics, their renal clearance and biodistribution also depend on initial injection doses and their dissociation processes. Quantitative understanding of size effect and other factors involved in renal clearance and biodistribution of degradable inorganic NPs will lay down a foundation for further development of renal-clearable inorganic NPs with minimized nanotoxicity. PMID:25674666

  2. An evaluation of hepatic extraction and clearance of doxorubicin.

    PubMed Central

    August, D. A.; Verma, N.; Vaertan, M. A.; Shah, R.; Brenner, D. E.

    1995-01-01

    A swine model was developed to study quantitatively the pharmacokinetics of hepatic extraction and clearance of doxorubicin (DOX). Systemic and hepatic artery infusions of DOX (0.5-9 mg kg-1) were administered to 34 pigs. Pharmacokinetic analysis was simplified by use of a double-balloon catheter in the inferior vena cava to collect hepatic venous effluent. During hepatic artery infusion only, DOX in hepatic venous blood was extracted using activated carbon filters to prevent drug recirculation. Hepatic extraction and clearance of DOX were independent of dose and route of administration. Extraction ratios varied from 0.75 to 0.91 during hepatic artery infusion and from 0.50 to 0.72 during systemic infusion. Clearance results were analogous. After cessation of drug infusions, hepatic extraction and clearance of DOX was negative, suggesting that the liver serves as a drug reservoir during DOX infusion and subsequently is a net source of unmetabolised drug. Liver extraction and clearance of DOX in pigs are substantial. During either systemic or hepatic artery infusion of DOX, the liver serves as a drug reservoir. Subsequent mobilisation of this hepatic pool of DOX may cause prolonged systemic exposure to drug. PMID:7599068

  3. Contribution of renal and non-renal clearance on increased total clearance of adalimumab in glomerular disease.

    PubMed

    Roberts, Brittney V; Susano, Isidro; Gipson, Debbie S; Trachtman, Howard; Joy, Melanie S

    2013-09-01

    The contribution of renal and non-renal clearance toward targeted concentrations and/or effects of therapeutic proteins in nephrotic patients are unknown. This study dissected the contribution of clearance pathways to adalimumab elimination in patients with focal segmental glomerulosclerosis (FSGS). Urine was collected from seven patients treated with adalimumab. Renal clearance (ClR ) was measured and non-renal clearance (ClNR ) was calculated as the difference between total clearance and ClR . Differences in cumulative amount in urine, ClR, and ClNR between study weeks 1 and 16 and relationships between proteinuria (protein:creatinine ratio (Up/c)), and ClR and ClNR were evaluated. Up to 13% of the adalimumab dose was lost in urine. ClNR contributed more than ClR to enhanced total clearance. There was a nonlinear relationship between Up/c and ClR (R(2) 0.7059); an increase in ClR beginning at Up/c of 12 mg/mg [slope 1.755, (C.I. -7.825 to 11.34)]. There was a linear relationship between Up/c and ClNR (R(2) 0.5039); for every one unit increase in Up/c, ClNR would increase by 3.5 mL/hr (P = 0.01). Both ClR and ClNR contribute to enhanced total clearance of adalimumab in glomerular disease secondary to FSGS. Additional research is needed to identify mechanisms for the increased ClNR pathways. PMID:23813330

  4. IRF8 directs stress-induced autophagy in macrophages and promotes clearance of Listeria monocytogenes.

    PubMed

    Gupta, Monica; Shin, Dong-Mi; Ramakrishna, Lakshmi; Goussetis, Dennis J; Platanias, Leonidas C; Xiong, Huabao; Morse, Herbert C; Ozato, Keiko

    2015-01-01

    Autophagy, activated by many stresses, plays a critical role in innate immune responses. Here we show that interferon regulatory factor 8 (IRF8) is required for the expression of autophagy-related genes in dendritic cells. Furthermore in macrophages, IRF8 is induced by multiple autophagy-inducing stresses, including IFNγ and Toll-like receptor stimulation, bacterial infection, starvation and by macrophage colony-stimulating factor. IRF8 directly activates many genes involved in various steps of autophagy, promoting autophagosome formation and lysosomal fusion. Consequently, Irf8(-/-) macrophages are deficient in autophagic activity, and excessively accumulate SQSTM1 and ubiquitin-bound proteins. We show that clearance of Listeria monocytogenes in macrophages requires IRF8-dependent activation of autophagy genes and subsequent autophagic capturing and degradation of Listeria antigens. These processes are defective in Irf8(-/-) macrophages where uninhibited bacterial growth ensues. Together these data suggest that IRF8 is a major autophagy regulator in macrophages, essential for macrophage maturation, survival and innate immune responses. PMID:25775030

  5. Clinical indicators of ineffective airway clearance in children with acute respiratory infection.

    PubMed

    Pascoal, Livia Maia; Lopes, Marcos Venícios de Oliveira; da Silva, Viviane Martins; Beltrão, Beatriz Amorim; Chaves, Daniel Bruno Resende; Herdman, T Heather; Lira, Ana Luisa Brandão de Carvalho; Teixeira, Iane Ximenes; Costa, Alice Gabrielle de Sousa

    2016-09-01

    The identification of clinical indicators with good predictive ability allows the nurse to minimize the existing variability in clinical situations presented by the patient and to accurately identify the nursing diagnosis, which represents the true clinical condition. The purpose of this study was to analyze the accuracy of NANDA-I clinical indicators of the nursing diagnosis ineffective airway clearance (IAC) in children with acute respiratory infection. This was a prospective cohort study conducted with a group of 136 children and followed for a period of time ranging from 6 to 10 consecutive days. For data analysis, the measures of accuracy were calculated for clinical indicators, which presented statistical significance in a generalized estimated equation model. IAC was present in 91.9% of children in the first assessment. Adventitious breath sounds presented the best measure of accuracy. Ineffective cough presented a high value of sensitivity. Changes in respiratory rate, wide-eyed, diminished breath sounds, and difficulty vocalizing presented high positive predictive values. In conclusion, adventitious breath sounds showed the best predictive ability to diagnose IAC in children with respiratory acute infection. PMID:26311487

  6. A CCR2 macrophage endocytic pathway mediates extravascular fibrin clearance in vivo

    PubMed Central

    Motley, Michael P.; Madsen, Daniel H.; Jürgensen, Henrik J.; Spencer, David E.; Szabo, Roman; Holmbeck, Kenn; Flick, Matthew J.; Lawrence, Daniel A.; Castellino, Francis J.; Weigert, Roberto

    2016-01-01

    Extravascular fibrin deposition accompanies many human diseases and causes chronic inflammation and organ damage, unless removed in a timely manner. Here, we used intravital microscopy to investigate how fibrin is removed from extravascular space. Fibrin placed into the dermis of mice underwent cellular endocytosis and lysosomal targeting, revealing a novel intracellular pathway for extravascular fibrin degradation. A C-C chemokine receptor type 2 (CCR2)-positive macrophage subpopulation constituted the majority of fibrin-uptaking cells. Consequently, cellular fibrin uptake was diminished by elimination of CCR2-expressing cells. The CCR2-positive macrophage subtype was different from collagen-internalizing M2-like macrophages. Cellular fibrin uptake was strictly dependent on plasminogen and plasminogen activator. Surprisingly, however, fibrin endocytosis was unimpeded by the absence of the fibrin(ogen) receptors, αMβ2 and ICAM-1, the myeloid cell integrin-binding site on fibrin or the endocytic collagen receptor, the mannose receptor. The study identifies a novel fibrin endocytic pathway engaged in extravascular fibrin clearance and shows that interstitial fibrin and collagen are cleared by different subsets of macrophages employing distinct molecular pathways. PMID:26647393

  7. A CCR2 macrophage endocytic pathway mediates extravascular fibrin clearance in vivo.

    PubMed

    Motley, Michael P; Madsen, Daniel H; Jürgensen, Henrik J; Spencer, David E; Szabo, Roman; Holmbeck, Kenn; Flick, Matthew J; Lawrence, Daniel A; Castellino, Francis J; Weigert, Roberto; Bugge, Thomas H

    2016-03-01

    Extravascular fibrin deposition accompanies many human diseases and causes chronic inflammation and organ damage, unless removed in a timely manner. Here, we used intravital microscopy to investigate how fibrin is removed from extravascular space. Fibrin placed into the dermis of mice underwent cellular endocytosis and lysosomal targeting, revealing a novel intracellular pathway for extravascular fibrin degradation. A C-C chemokine receptor type 2 (CCR2)-positive macrophage subpopulation constituted the majority of fibrin-uptaking cells. Consequently, cellular fibrin uptake was diminished by elimination of CCR2-expressing cells. The CCR2-positive macrophage subtype was different from collagen-internalizing M2-like macrophages. Cellular fibrin uptake was strictly dependent on plasminogen and plasminogen activator. Surprisingly, however, fibrin endocytosis was unimpeded by the absence of the fibrin(ogen) receptors, αMβ2 and ICAM-1, the myeloid cell integrin-binding site on fibrin or the endocytic collagen receptor, the mannose receptor. The study identifies a novel fibrin endocytic pathway engaged in extravascular fibrin clearance and shows that interstitial fibrin and collagen are cleared by different subsets of macrophages employing distinct molecular pathways. PMID:26647393

  8. Histamine 1 Receptor Blockade Enhances Eosinophil-Mediated Clearance of Adult Filarial Worms

    PubMed Central

    Fox, Ellen Mueller; Morris, Christopher P.; Hübner, Marc P.; Mitre, Edward

    2015-01-01

    Filariae are tissue-invasive nematodes that cause diseases such as elephantiasis and river blindness. The goal of this study was to characterize the role of histamine during Litomosoides sigmodontis infection of BALB/c mice, a murine model of filariasis. Time course studies demonstrated that while expression of histidine decarboxylase mRNA increases throughout 12 weeks of infection, serum levels of histamine exhibit two peaks—one 30 minutes after primary infection and one 8 weeks later. Interestingly, mice treated with fexofenadine, a histamine receptor 1 inhibitor, demonstrated significantly reduced worm burden in infected mice compared to untreated infected controls. Although fexofenadine-treated mice had decreased antigen-specific IgE levels as well as lower splenocyte IL-5 and IFNγ production, they exhibited a greater than fourfold rise in eosinophil numbers at the tissue site where adult L. sigmodontis worms reside. Fexofenadine-mediated clearance of L. sigmodontis worms was dependent on host eosinophils, as fexofenadine did not decrease worm burdens in eosinophil-deficient dblGATA mice. These findings suggest that histamine release induced by tissue invasive helminths may aid parasite survival by diminishing eosinophilic responses. Further, these results raise the possibility that combining H1 receptor inhibitors with current anthelmintics may improve treatment efficacy for filariae and other tissue-invasive helminths. PMID:26204515

  9. Facial bacterial infections: folliculitis.

    PubMed

    Laureano, Ana Cristina; Schwartz, Robert A; Cohen, Philip J

    2014-01-01

    Facial bacterial infections are most commonly caused by infections of the hair follicles. Wherever pilosebaceous units are found folliculitis can occur, with the most frequent bacterial culprit being Staphylococcus aureus. We review different origins of facial folliculitis, distinguishing bacterial forms from other infectious and non-infectious mimickers. We distinguish folliculitis from pseudofolliculitis and perifolliculitis. Clinical features, etiology, pathology, and management options are also discussed. PMID:25441463

  10. Demonstrating Bacterial Flagella.

    ERIC Educational Resources Information Center

    Porter, John R.; And Others

    1992-01-01

    Describes an effective laboratory method for demonstrating bacterial flagella that utilizes the Proteus mirabilis organism and a special harvesting technique. Includes safety considerations for the laboratory exercise. (MDH)

  11. Periodic response of multi-disk rotors with bearing clearances

    NASA Technical Reports Server (NTRS)

    Kim, Y. B.; Noah, S. T.; Choi, Y. S.

    1991-01-01

    The forced steady state response of a multi-disk rotor system involving a clearance at one of the bearings is determined by using a harmonic balance approach. The impedance method is applied to each of the harmonic steady state components in order to reduce the system to its displacement at the nonlinear bearing support. The results reveal the interrelated roles of the bearing clearance, mass eccentricity and side force in producing dangerous subharmonics. The significant effects of the strong nonlinearity of a bearing clearance are studied as related to the various system parameters. The results show that the approach developed in this study is computationally superior to numerical integration methods in analyzing multi-disk rotor systems with strong nonlinearity.

  12. Periodic response of multi-disk rotors with bearing clearances

    NASA Astrophysics Data System (ADS)

    Kim, Y. B.; Noah, S. T.; Choi, Y. S.

    1991-02-01

    The forced steady state response of a multi-disk rotor system involving a clearance at one of the bearings is determined by using a harmonic balance approach. The impedance method is applied to each of the harmonic steady state components in order to reduce the system to its displacement at the non-linear bearing support. The results reveal the interrelated roles of the bearing clearance, mass eccentricity and side force in producing dangerous subharmonics. The significant effects of the strong non-linearity of a bearing clearance are studied as related to the various system parameters. The results show that the approach developed in this study is computationally superior to numerical integration methods in analyzing multi-disk rotor systems with strong non-linearity.

  13. HPT Clearance Control: Intelligent Engine Systems-Phase 1

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The following work has been completed to satisfy the Phase I Deliverables for the "HPT Clearance Control" project under NASA GRC's "Intelligent Engine Systems" program: (1) Need for the development of an advanced HPT ACC system has been very clearly laid out, (2) Several existing and potential clearance control systems have been reviewed, (3) A scorecard has been developed to document the system, performance (fuel burn, range, payload, etc.), thermal, and mechanical characteristics of the existing clearance control systems, (4) Engine size and flight cycle selection for the advanced HPT ACC system has been reviewed with "large engine"/"long range mission" combination showing the most benefit, (5) A scoring criteria has been developed to tie together performance parameters for an objective, data driven comparison of competing systems, and (6) The existing HPT ACC systems have been scored based on this scoring system.

  14. Bromosulphophthalein clearance rates in sheep with pyrrolizidine liver damage.

    PubMed

    Lanigan, G W; Peterson, J E

    1979-05-01

    Sheep fed a ration containing 50% of dried Heliotropium europaeum showed a marked decline in bromosulphophthalein (BSP) fractional clearance rate during the first 3 months feeding. Thereafter, the response of individual animals varied widely on a time basis, although 3 groups could be identified. In the terminal stages, mean clearance rates were below 20% of initial values, with some sheep showing a decline in excess of 90%. Loss of liver functional capacity was generally much greater than indicated by the degree of damage revealed by histopathology. Thus, a suitably modified test could have considerable prognostic value in the field. In this investigation, all sheep with clearance rates below 0.15 died when exposed to a further period of H. europaeum feeding. PMID:475677

  15. Inefficient clearance of myelin debris by microglia impairs remyelinating processes

    PubMed Central

    Lampron, Antoine; Larochelle, Antoine; Laflamme, Nathalie; Préfontaine, Paul; Plante, Marie-Michèle; Sánchez, Maria Gabriela; Yong, V. Wee; Stys, Peter K.; Tremblay, Marie-Ève

    2015-01-01

    An imbalance between remyelinating and demyelinating rates underlies degenerative processes in demyelinating diseases such as multiple sclerosis. An optimal therapeutic strategy would be to stimulate remyelination while limiting demyelination. Although accumulation of myelin debris impairs remyelination, the mechanisms regulating the clearance of such debris by mononuclear phagocytic cells are poorly understood. We demonstrate that after cuprizone intoxication, CCR2-dependent infiltration of mouse bone marrow–derived cells is abundant in demyelinating areas, but that these cells do not impact demyelination. However, in CX3CR1-deficient mice, the clearance of myelin debris by microglia was blocked greatly, affecting the integrity of the axon and myelin sheaths and thus preventing proper remyelination. These results highlight the crucial role played by CX3CR1 in myelin removal and show that there can be no efficient remyelination after a primary demyelinating insult if myelin clearance by microglia is impaired. PMID:25779633

  16. Application of Dsm in Obstacle Clearance Surveying of Aerodrome

    NASA Astrophysics Data System (ADS)

    Qiao, X.; Lv, S. H.; Li, L. L.; Zhou, X. J.; Wang, H. Y.; Li, D.; Liu, J. Y.

    2016-06-01

    Compared to the wide use of digital elevation model (DEM), digital surface model (DSM) receives less attention because that it is composed by not only terrain surface, but also vegetations and man-made objects which are usually regarded as useless information. Nevertheless, these objects are useful for the identification of obstacles around an aerodrome. The primary objective of the study was to determine the applicability of DSM in obstacle clearance surveying of aerodrome. According to the requirements of obstacle clearance surveying at QT airport, aerial and satellite imagery were used to generate DSM, by means of photogrammetry, which was spatially analyzed with the hypothetical 3D obstacle limitation surfaces (OLS) to identify the potential obstacles. Field surveying was then carried out to retrieve the accurate horizontal position and height of the obstacles. The results proved that the application of DSM could make considerable improvement in the efficiency of obstacle clearance surveying of aerodrome.

  17. Fiber-optic laser Doppler turbine tip clearance probe

    NASA Astrophysics Data System (ADS)

    Büttner, Lars; Pfister, Thorsten; Czarske, Jürgen

    2006-05-01

    A laser Doppler based method for in situ single blade tip clearance measurements of turbomachines with high precision is presented for what we believe is the first time. The sensor is based on two superposed fanlike interference fringe systems generated by two laser wavelengths from a fiber-coupled, passive, and therefore compact measurement head employing diffractive optics. Tip clearance measurements at a transonic centrifugal compressor performed during operation at 50,000 rpm (833 Hz, 586 m/s tip speed) are reported. At these speeds the measured uncertainty of the tip position was less than 20 μm, a factor of 2 more accurate than that of capacitive probes. The sensor offers great potential for in situ and online high-precision tip clearance measurements of metallic and nonmetallic turbine blades.

  18. Fiber-optic laser Doppler turbine tip clearance probe.

    PubMed

    Büttner, Lars; Pfister, Thorsten; Czarske, Jürgen

    2006-05-01

    A laser Doppler based method for in situ single blade tip clearance measurements of turbomachines with high precision is presented for what we believe is the first time. The sensor is based on two superposed fanlike interference fringe systems generated by two laser wavelengths from a fiber-coupled, passive, and therefore compact measurement head employing diffractive optics. Tip clearance measurements at a transonic centrifugal compressor performed during operation at 50,000 rpm (833 Hz, 586 m/s tip speed) are reported. At these speeds the measured uncertainty of the tip position was less than 20 microm, a factor of 2 more accurate than that of capacitive probes. The sensor offers great potential for in situ and online high-precision tip clearance measurements of metallic and nonmetallic turbine blades. PMID:16642064

  19. Impaired lipid clearance in patients with previous acute pancreatitis.

    PubMed Central

    Guzmán, S; Nervi, F; Llanos, O; León, P; Valdivieso, V

    1985-01-01

    Fasting serum triglycerides were measured in 52 patients who had sustained an attack of pancreatitis (gall stone related 33, alcoholism six) at least six months earlier. Several patients (23%) had raised fasting serum triglycerides, with a type IV phenotype in all but one patient. The 40 patients with normal fasting serum triglycerides received an oral load of 100 g sunflower oil to compare their clearance of dietary triglycerides with that of a control group of 54 subjects. The clearance of ingested triglycerides was significantly impaired in the patients - irrespective of the presumed aetiological factor, or clinical condition associated with pancreatitis - compared with the clearance in controls. A triglyceride tolerance test is the only way to detect those patients in whom a future attack of pancreatitis may be precipitated by a diet rich in fat, or endogenous over production of triglycerides as after an alcoholic debauch. PMID:4029716

  20. Effect of Internal Clearance on Load Distribution and Life of Radially Loaded Ball and Roller Bearings

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

    2012-01-01

    The effect of internal clearance on radially loaded deepgroove ball and cylindrical roller bearing load distribution and fatigue life was determined for four clearance groups defined in the bearing standards. The analysis was extended to negative clearance (interference) conditions to produce a curve of life factor versus internal clearance. Rolling-element loads can be optimized and bearing life maximized for a small negative operating clearance. Life declines gradually with positive clearance and rapidly with increasing negative clearance. Relationships were found between bearing life and internal clearance as a function of ball or roller diameter, adjusted for load. Results are presented as life factors for radially loaded bearings independent of bearing size or applied load. In addition, a modified Stribeck Equation is presented that relates the maximum rolling-element load to internal bearing clearance.

  1. Acute exposure to acid fog. Effects on mucociliary clearance

    SciTech Connect

    Laube, B.L.; Bowes, S.M. III; Links, J.M.; Thomas, K.K.; Frank, R. )

    1993-05-01

    Submicrometric sulfuric acid (H2SO4) aerosol can affect mucociliary clearance without eliciting irritative symptoms or changes in pulmonary function. The effect of larger fog droplets containing H2SO4 on mucociliary clearance is unknown. We quantified mucociliary clearance from the trachea (n = 4) and small airways (n = 7) of young healthy male adults after an acute exposure to H2SO4 fog (MMAD = 10.3 microns; pH = 2.0; liquid water content = 481 +/- 65 mg/m3; osmolarity = 30 mOsm). Acid fog (AF) or saline fog (SF) (10.9 microns; 492 +/- 116 mg/m3; 30 mOsm) was administered for 40 min of unencumbered breathing (no mouth-piece) at rest and for 20 min of exercise sufficient to produce oronasal breathing. Fog exposures were followed by a methacholine (MCh) challenge (a measure of airway reactivity) or inhalation of technetium-99M radioaerosol (MMAD = 3.4 microns) on 2 study days each. Changes in symptoms and forced ventilatory function were also assessed. Clearance was quantified from computer-assisted analyses of gamma camera images of the lower respiratory tract in terms of %removal/min of the radiolabel from the trachea 25 min after inhalation and from the outer zone of the right lung after 1.9 to 3 h. Symptoms, forced ventilatory function, and MCh response were unaffected by either fog. Tracheal clearance was more rapid in four of four subjects after AF (0.83 +/- 1.58% removal/min) compared with that after SF (-0.54 +/- 0.85% removal/min). Outer zone clearance was more rapid in six of seven subjects after AF (0.22 +/- 0.15% removal/min) compared with that after SF (0.01 +/- 0.09% removal/min).

  2. Modulation of lung liquid clearance by isoproterenol in rat lungs.

    PubMed

    Saldías, F; Lecuona, E; Friedman, E; Barnard, M L; Ridge, K M; Sznajder, J I

    1998-05-01

    beta-Adrenergic agonists have been reported to increase lung liquid clearance by stimulating active Na+ transport across the alveolar epithelium. We studied mechanisms by which beta-adrenergic isoproterenol (Iso) increases lung liquid clearance in isolated perfused fluid-filled rat lungs. Iso perfused through the pulmonary circulation at concentrations of 10(-4) to 10(-8) M increased lung liquid clearance compared with that of control lungs (P < 0.01). The increase in lung liquid clearance was inhibited by the beta-antagonist propranolol (10(-5) M), the Na(+)-channel blocker amiloride (10(-4) M), and the antagonist of Na-K-ATPase, ouabain (5 x 10(-4) M). Colchicine, which inhibits cell microtubular transport of ion-transporting proteins to the plasma membrane, blocked the stimulatory effects of Iso on active Na+ transport, whereas the isomer lumicolchicine, which does not affect cell microtubular transport, did not inhibit Na+ transport. In parallel with these changes, the Na-K-ATPase alpha 1-subunit protein abundance and activity increased in alveolar type II cells stimulated by 10(-6) M Iso. Colchicine blocked the stimulatory effect of Iso and the recruitment of Na-K-ATPase alpha 1-protein to the basolateral membrane of alveolar type II cells. Accordingly, Iso increased active Na+ transport and lung liquid clearance by stimulation of beta-adrenergic receptors and probably by upregulation of apical Na+ channels and basolateral Na-K-ATPase mechanisms. Recruitment from intracellular pools and microtubular transport of Na+ pumps to the plasma membrane participate in beta-adrenergic stimulation of lung liquid clearance in rat lungs. PMID:9612284

  3. Effects of desipramine on norepinephrine clearance in congestive heart failure

    SciTech Connect

    Clemson, B.; Baily, R.G.; Davis, D.; Zelis, R. )

    1990-08-01

    Elevated plasma norepinephrine (NE) in congestive heart failure (CHF) is caused by increased NE spillover and decreased NE clearance. To evaluate the effects of neuronal uptake blockade on NE clearance, we studied NE kinetics during steady-state infusions of (3H)NE, before and after oral desipramine (DMI, 50 mg) in 11 patients with CHF and 8 normal volunteers. Baseline plasma NE was greater in the CHF group (637 +/- 56 vs. 271 +/- 32 pg/ml; P less than 0.001), NE clearance was lower in CHF (1.31 +/- 0.21 vs. 1.94 +/- 0.17 l.min-1.m-2; P = 0.026), and NE spillover was greater in CHF (4.71 +/- 0.78 vs. 3.04 +/- 0.35 nmol.min-1.m-2, P = 0.054). After DMI, plasma NE rose significantly in CHF (778 +/- 67; P = 0.008), and NE clearance decreased further in CHF (0.97 +/- 0.16; P = 0.024), but neither changed in normal subjects. NE spillover did not change in either group. There appears to be an enhanced effect of DMI on NE clearance in CHF patients. Two general mechanisms may be responsible for this finding, an increased concentration of drug, possibly caused by a decreased volume of distribution, and an increased sensitivity of neuronal amine pumps to DMI. Both mechanisms may reflect a more general abnormality of clearance of drugs and hormones related to abnormalities of tissue perfusion in CHF.

  4. Mucociliary clearance, airway inflammation and nasal symptoms in urban motorcyclists

    PubMed Central

    Brant, Tereza C S; Yoshida, Carolina T; de S. Carvalho, Tomas; Nicola, Marina L; Martins, Jocimar A; Braga, Lays M; de Oliveira, Regiani C; Leyton, Vilma; de André, Carmen S; Saldiva, Paulo H N; Rubin, Bruce K; Nakagawa, Naomi K

    2014-01-01

    OBJECTIVES: There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution. METHODS: In total, 25 non-smoking commercial motorcyclists, aged 18-44 years, were included in this study. These drivers work 8-12 hours per day, 5 days per week, driving on urban streets. Nasal mucociliary clearance was measured by the saccharine transit test; airway acidification was measured by assessing the pH of exhaled breath condensate; and airway symptoms were measured by the Sino-nasal Outcome Test-20 questionnaire. To assess personal air pollution exposure, the subjects used a passive-diffusion nitrogen dioxide (NO2) concentration-monitoring system during the 14 days before each assessment. The associations between NO2 and the airway outcomes were analyzed using the Mann-Whitney test and the Chi-Square test. Clinicaltrials.gov: NCT01976039. RESULTS: Compared with clearance in healthy adult males, mucociliary clearance was decreased in 32% of the motorcyclists. Additionally, 64% of the motorcyclists had airway acidification and 92% experienced airway symptoms. The median personal NO2 exposure level was 75 mg/m3 for these subjects and a significant association was observed between NO2 and impaired mucociliary clearance (p = 0.036). CONCLUSION: Non-smoking commercial motorcyclists exhibit increased airway symptoms and airway acidification as well as decreased nasal mucociliary clearance, all of which are significantly associated with the amount of exposure to air pollution. PMID:25628001

  5. Ventral striatal hypoactivation is associated with apathy but not diminished expression in patients with schizophrenia

    PubMed Central

    Kirschner, Matthias; Hager, Oliver M.; Bischof, Martin; Hartmann, Matthias N.; Kluge, Agne; Seifritz, Erich; Tobler, Philippe N.; Kaiser, Stefan

    2016-01-01

    Background Negative symptoms of schizophrenia can be grouped in 2 dimensions: apathy and diminished expression. Increasing evidence suggests that negative symptoms are associated with altered neural activity of subcortical and cortical regions in the brain reward system. However, the neurobiological basis of the distinct symptom dimensions within negative symptoms is still poorly understood. The primary aim of our study was to examine the neural correlates of the negative symptom dimensions apathy and diminished expression during a reward processing task. Methods Patients with schizophrenia and healthy controls underwent event-related fMRI while performing a variant of the Monetary Incentive Delay Task. We assessed negative symptom dimensions using the Brief Negative Symptom Scale. Results We included 27 patients and 25 controls in our study. Both groups showed neural activation indicated by blood oxygen–level dependent signal in the ventral striatum during reward anticipation. Ventral striatal activation during reward anticipation showed a strong negative correlation with apathy. Importantly, this effect was not driven by cognitive ability, medication, depressive or positive symptoms. In contrast, no significant correlation with the diminished expression dimension was observed. Limitations Although the results remain significant when controlling for chlorpromazine equivalents, we cannot fully exclude potential confounding effects of medication with atypical antipsychotics. Conclusion The specific correlation of ventral striatal hypoactivation during reward anticipation with apathy demonstrates a differentiation of apathy and diminished expression on a neurobiological level and provides strong evidence for different pathophysiological mechanisms underlying these 2 negative symptom dimensions. Our findings contribute to a multilevel framework in which apathy and motivational impairment in patients with schizophrenia can be described on psychopathological

  6. Diminished growth hormone secretion in blind males after L-dopa stimulation.

    PubMed

    Fatranská, M; Jurcovicová, J; Németh, S; Vigas, M

    1988-12-01

    Growth hormone secretion after L-dopa administration (1000 mg p.o.) was investigated in young adult normal and blind volunteers. The average increment of plasma growth hormone after L-dopa stimulation in the blind was below the criterion for a positive response (less than 5 ng ml-1). The control volunteers showed normal response. After L-dopa stimulation there was a significantly diminished growth hormone response in the young adult blind compared to control volunteers. PMID:3243205

  7. Diminished self-conscious emotional responding in frontotemporal lobar degeneration patients.

    PubMed

    Sturm, Virginia E; Ascher, Elizabeth A; Miller, Bruce L; Levenson, Robert W

    2008-12-01

    Frontotemporal lobar degeneration (FTLD) is a neurodegenerative disease that dramatically alters social and emotional behavior. Recent work has suggested that self-conscious emotions (e.g., embarrassment) may be particularly vulnerable to disruption in this disease. Self-conscious emotions require the ability to monitor the self in relation to others. These abilities are thought to be subserved by brain regions (e.g., medial prefrontal, anterior cingulate, and insula) that are particularly vulnerable to damage in FTLD. This study examined emotional responding (expressive behavior, peripheral physiology, and subjective experience) in 24 FTLD patients and 16 cognitively normal control participants using a karaoke task known to elicit self-conscious emotion reliably and a nonemotional control task (isometric handgrip). Results indicated that FTLD patients showed diminished self-conscious emotional behavior (embarrassment and amusement) and diminished physiological responding while watching themselves singing. No differences were found between patients and controls in the nonemotional control task. These findings offer evidence of marked disruption of self-conscious emotional responding in FTLD. Diminished self-conscious emotional responding likely contributes significantly to social inappropriateness and other behavioral abnormalities in FTLD. PMID:19102597

  8. Diminished Self-Conscious Emotional Responding in Frontotemporal Lobar Degeneration Patients

    PubMed Central

    Sturm, Virginia E.; Ascher, Elizabeth A.; Miller, Bruce L.; Levenson, Robert W.

    2009-01-01

    Frontotemporal lobar degeneration (FTLD) is a neurodegenerative disease that dramatically alters social and emotional behavior. Recent work has suggested that self-conscious emotions (e.g., embarrassment) may be particularly vulnerable to disruption in this disease. Self-conscious emotions require the ability to monitor the self in relation to others. These abilities are thought to be subserved by brain regions (e.g., medial prefrontal, anterior cingulate, and insula) that are particularly vulnerable to damage in FTLD. This study examined emotional responding (expressive behavior, peripheral physiology, and subjective experience) in 24 FTLD patients and 16 cognitively normal control participants using a karaoke task known to elicit self-conscious emotion reliably and a nonemotional control task (isometric handgrip). Results indicated that FTLD patients showed diminished self-conscious emotional behavior (embarrassment and amusement) and diminished physiological responding while watching themselves singing. No differences were found between patients and controls in the nonemotional control task. These findings offer evidence of marked disruption of self-conscious emotional responding in FTLD. Diminished self-conscious emotional responding likely contributes significantly to social inappropriateness and other behavioral abnormalities in FTLD. PMID:19102597

  9. The association of neurocognitive impairment with diminished expression and apathy in schizophrenia.

    PubMed

    Hartmann-Riemer, Matthias N; Hager, Oliver M; Kirschner, Matthias; Bischof, Martin; Kluge, Agne; Seifritz, Erich; Kaiser, Stefan

    2015-12-01

    Negative symptoms can be grouped into the two dimensions of diminished expression and apathy, which have been shown to be dissociable regarding external validators, such as functional outcome. Here, we investigated whether these two dimensions differentially relate to neurocognitive impairment in schizophrenia. 47 patients with schizophrenia or schizoaffective disorder and 33 healthy control participants were subjected to a neurocognitive test battery assessing multiple cognitive domains (processing speed, working memory, verbal fluency, verbal learning and memory, mental planning), which are integrated into a composite cognition score. Negative symptoms in patients were assessed using the Brief Negative Symptom Scale. We found that diminished expression significantly related to neurocognitive impairment, while severity of apathy symptoms was not directly associated with neurocognition. Other assessed clinical variables include chlorpromazine equivalents, positive symptoms, and depressive symptoms and did not influence the results. Our results are in line with a cognitive resource limitation model of diminished expression in schizophrenia and indicate that cognitive remediation therapy might be helpful to ameliorate expressive deficits. PMID:26526750

  10. Vimentin in Bacterial Infections

    PubMed Central

    Mak, Tim N.; Brüggemann, Holger

    2016-01-01

    Despite well-studied bacterial strategies to target actin to subvert the host cell cytoskeleton, thus promoting bacterial survival, replication, and dissemination, relatively little is known about the bacterial interaction with other components of the host cell cytoskeleton, including intermediate filaments (IFs). IFs have not only roles in maintaining the structural integrity of the cell, but they are also involved in many cellular processes including cell adhesion, immune signaling, and autophagy, processes that are important in the context of bacterial infections. Here, we summarize the knowledge about the role of IFs in bacterial infections, focusing on the type III IF protein vimentin. Recent studies have revealed the involvement of vimentin in host cell defenses, acting as ligand for several pattern recognition receptors of the innate immune system. Two main aspects of bacteria-vimentin interactions are presented in this review: the role of vimentin in pathogen-binding on the cell surface and subsequent bacterial invasion and the interaction of cytosolic vimentin and intracellular pathogens with regards to innate immune signaling. Mechanistic insight is presented involving distinct bacterial virulence factors that target vimentin to subvert its function in order to change the host cell fate in the course of a bacterial infection. PMID:27096872

  11. Bacterial Ion Channels.

    PubMed

    Compton, Emma L R; Mindell, Joseph A

    2010-09-01

    Bacterial ion channels were known, but only in special cases, such as outer membrane porins in Escherichia coli and bacterial toxins that form pores in their target (bacterial or mammalian) membranes. The exhaustive coverage provided by a decade of bacterial genome sequencing has revealed that ion channels are actually widespread in bacteria, with homologs of a broad range of mammalian channel proteins coded throughout the bacterial and archaeal kingdoms. This review discusses four groups of bacterial channels: porins, mechano-sensitive (MS) channels, channel-forming toxins, and bacterial homologs of mammalian channels. The outer membrane (OM) of gram-negative bacteria blocks access of essential nutrients; to survive, the cell needs to provide a mechanism for nutrients to penetrate the OM. Porin channels provide this access by forming large, nonspecific aqueous pores in the OM that allow ions and vital nutrients to cross it and enter the periplasm. MS channels act as emergency release valves, allowing solutes to rapidly exit the cytoplasm and to dissipate the large osmotic disparity between the internal and external environments. MS channels are remarkable in that they do this by responding to forces exerted by the membrane itself. Some bacteria produce toxic proteins that form pores in trans, attacking and killing other organisms by virtue of their pore formation. The review focuses on those bacterial toxins that kill other bacteria, specifically the class of proteins called colicins. Colicins reveal the dangers of channel formation in the plasma membrane, since they kill their targets with exactly that approach. PMID:26443789

  12. Vimentin in Bacterial Infections.

    PubMed

    Mak, Tim N; Brüggemann, Holger

    2016-01-01

    Despite well-studied bacterial strategies to target actin to subvert the host cell cytoskeleton, thus promoting bacterial survival, replication, and dissemination, relatively little is known about the bacterial interaction with other components of the host cell cytoskeleton, including intermediate filaments (IFs). IFs have not only roles in maintaining the structural integrity of the cell, but they are also involved in many cellular processes including cell adhesion, immune signaling, and autophagy, processes that are important in the context of bacterial infections. Here, we summarize the knowledge about the role of IFs in bacterial infections, focusing on the type III IF protein vimentin. Recent studies have revealed the involvement of vimentin in host cell defenses, acting as ligand for several pattern recognition receptors of the innate immune system. Two main aspects of bacteria-vimentin interactions are presented in this review: the role of vimentin in pathogen-binding on the cell surface and subsequent bacterial invasion and the interaction of cytosolic vimentin and intracellular pathogens with regards to innate immune signaling. Mechanistic insight is presented involving distinct bacterial virulence factors that target vimentin to subvert its function in order to change the host cell fate in the course of a bacterial infection. PMID:27096872

  13. Fungal and Bacterial Diseases.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal and bacterial diseases are important constraints to production. Recognition of diseases and information on their biology is important in disease management. This chapter is aimed at providing diagnostic information on fungal and bacterial diseases of sugar beet and their biology, epidemiolo...

  14. Effects of sodium methyldithiocarbamate on selected parameters of innate immunity and clearance of bacteria in a mouse model of sepsis

    PubMed Central

    Tan, Wei; Pruett, Stephen B.

    2016-01-01

    Aims Sodium methyldithiocarbamate (SMD), the third most widely used conventional pesticide in the United States, has been reported to inhibit several parameters associated with inflammation and to decrease resistance to infection. In a previous study, survival time was markedly decreased when mice were treated orally with SMD shortly before challenge with a high dose of Escherichia coli (E. coli) that was lethal to most of the control mice. In the present study, we evaluated selected parameters of the innate immune system using a lower challenge dose of E. coli, to determine which (if any) of these parameters reflected continued changes through 24 h. Main methods Bacterial clearance from the peritoneal cavity, production of chemokines and cytokines, and body temperature were measured. Key findings All these parameters were reduced by SMD up to 12 h after bacterial challenge, but the concentration of the anti-inflammatory cytokine IL-10 was increased. Even so, mice in the control and SMD-treated groups cleared most bacteria by 24 h. Other parameters (cytokine concentrations and body temperature) were also normal or near normal by 24 h. The same dosage of SMD administered intranasally also did not significantly decrease survival. Hypothermia from 16 to 28 h correlated with lethal outcome, but SMD significantly increased hypothermia only at 2 and 4 h after challenge. Significance In spite of substantial early inhibition by SMD of parameters known to be important for resistance to infection, bacterial clearance and survival were not altered, suggesting immunological reserve and/or rapid recovery after transient effects of SMD. PMID:26281915

  15. Linking increased airway hydration, ciliary beating, and mucociliary clearance through ENaC inhibition

    PubMed Central

    Hemmerling, Martin; Root, James; Wingren, Cecilia; Pesic, Jelena; Johansson, Edvin; Garland, Alaina L.; Ghosh, Arunava; Tarran, Robert

    2014-01-01

    Airway dehydration causes mucus stasis and bacterial overgrowth in cystic fibrosis and chronic bronchitis (CB). Rehydration by hypertonic saline is efficacious but suffers from a short duration of action. We tested whether epithelial sodium channel (ENaC) inhibition would rehydrate normal and dehydrated airways to increase mucociliary clearance (MCC) over a significant time frame. For this, we used a tool compound (Compound A), which displays nanomolar ENaC affinity and retention in the airway surface liquid (ASL). Using normal human bronchial epithelial cultures (HBECs) grown at an air-liquid interface, we evaluated in vitro potency and efficacy using short-circuit current (Isc) and ASL height measurements where it inhibited Isc and increased ASL height by ∼50% (0.052 μM at 6 h), respectively. The in vivo efficacy was investigated in a modified guinea pig tracheal potential difference model, where we observed an effective dose (ED50) of 5 μg/kg (i.t.), and by MCC measures in rats and sheep, where we demonstrated max clearance rates at 100 μg/kg (i.t.) and 75 μg/kg (i.t.), respectively. Acute cigarette smoke-induced ASL height depletion in HBECs was used to mimic the situation in patients with CB, and pretreatment prevented both cigarette smoke-induced ASL dehydration and lessened the decrease in ciliary beat frequency. Furthermore, when added after cigarette smoke exposure, Compound A increased the rate of ASL rehydration. In conclusion, Compound A demonstrated significant effects and a link between increased airway hydration, ciliary function, and MCC. These data support the hypothesis that ENaC inhibition may be efficacious in the restoration of mucus hydration and transport in patients with CB. PMID:25361567

  16. Airway Epithelial NF-κB Activation Promotes Mycoplasma pneumoniae Clearance in Mice

    PubMed Central

    Jiang, Di; Nelson, Mark L.; Gally, Fabienne; Smith, Sean; Wu, Qun; Minor, Maisha; Case, Stephanie; Thaikoottathil, Jyoti; Chu, Hong Wei

    2012-01-01

    Background/Objective Respiratory infections including atypical bacteria Mycoplasma pneumoniae (Mp) contribute to the pathobiology of asthma and chronic obstructive pulmonary disease (COPD). Mp infection mainly targets airway epithelium and activates various signaling pathways such as nuclear factor κB (NF-κB). We have shown that short palate, lung, and nasal epithelium clone 1 (SPLUNC1) serves as a novel host defense protein and is up-regulated upon Mp infection through NF-κB activation in cultured human and mouse primary airway epithelial cells. However, the in vivo role of airway epithelial NF-κB activation in host defense against Mp infection has not been investigated. In the current study, we investigated the effects of in vivo airway epithelial NF-κB activation on lung Mp clearance and its association with airway epithelial SPLUNC1 expression. Methodology/Main Results Non-antimicrobial tetracycline analog 9-t-butyl doxycycline (9-TB) was initially optimized in mouse primary tracheal epithelial cell culture, and then utilized to induce in vivo airway epithelial specific NF-κB activation in conditional NF-κB transgenic mice (CC10-CAIKKβ) with or without Mp infection. Lung Mp load and inflammation were evaluated, and airway epithelial SPLUNC1 protein was examined by immunohistochemistry. We found that 9-TB treatment in NF-κB transgene positive (Tg+), but not transgene negative (Tg−) mice significantly reduced lung Mp load. Moreover, 9-TB increased airway epithelial SPLUNC1 protein expression in NF-κB Tg+ mice. Conclusion By using the non-antimicrobial 9-TB, our study demonstrates that in vivo airway epithelial NF-κB activation promotes lung bacterial clearance, which is accompanied by increased epithelial SPLUNC1 expression. PMID:23285237

  17. 33 CFR 151.1508 - Revocation of clearance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Revocation of clearance. 151.1508 Section 151.1508 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE,...

  18. 5 CFR 720.307 - Interagency report clearance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Interagency report clearance. 720.307 Section 720.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) AFFIRMATIVE EMPLOYMENT PROGRAMS Disabled Veterans Affirmative Action Program §...

  19. 5 CFR 720.307 - Interagency report clearance.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Interagency report clearance. 720.307 Section 720.307 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) AFFIRMATIVE EMPLOYMENT PROGRAMS Disabled Veterans Affirmative Action Program §...

  20. 7 CFR 1927.55 - Title clearance services.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true Title clearance services. 1927.55 Section 1927.55... acquired by assumption or with loan funds, or involving the borrower or the seller exist; (5) If a water right is to be included in the security for the loan, and if so, the full legal description of the...