Relevant bibliographies by topics / NTHi

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  2. Dissertations / Theses
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Academic literature on the topic 'NTHi'

Author: Grafiati
Published: 4 June 2021
Last updated: 20 February 2023

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Journal articles on the topic "NTHi"

1

Jiang, Zili, Nobuo Nagata, Edgar Molina, Lauren O. Bakaletz, Hal Hawkins, and Janak A. Patel. "Fimbria-Mediated Enhanced Attachment of NontypeableHaemophilus influenzae to Respiratory Syncytial Virus-Infected Respiratory Epithelial Cells." Infection and Immunity 67, no. 1 (January 1, 1999): 187–92. http://dx.doi.org/10.1128/iai.67.1.187-192.1999.

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ABSTRACT Respiratory syncytial virus (RSV) infection is known to predispose children to otitis media and sinusitis due to bacteria such as nontypeable Haemophilus influenzae (NTHI). In this study, we investigated the role of NTHI surface outer membrane protein P5-homologous fimbriae (P5-fimbriae) in attachment to RSV-exposed A549 epithelial cells. Analysis by fluorescence flow cytometry showed that a live P5-fimbriated NTHI strain (NTHIF+) attached to a higher proportion of RSV-exposed A549 cells than to control cells (mean, 68% for RSV versus 29% for control; P = 0.008), while attachment of the P5-fimbriae-deficient isogenic mutant strain (NTHIF−) was significantly lower than in control cells and rose only slightly following RSV exposure (mean, 17% for RSV versus 10% for control, P = 0.229). Attachment of NTHIF+ did not correlate with the amount of RSV antigen expressed by A549 cells. Furthermore, paraformaldehyde-fixed NTHIF+ also demonstrated an enhanced binding to RSV-exposed cells. Observations by transmission electronic microscopy showed that the mean number of bacteria attached per 100 RSV-exposed A549 cells was higher for NTHIF+ than NTHIF− (99 versus 18; P < 0.001). No intracellular bacteria were identified. UV-irradiated conditioned supernatants collected from RSV-infected A549 cultures (UV-cRSV) also enhanced the attachment of NTHIF+ to A549, suggesting the presence of a preformed soluble mediator(s) in UV-cRSV that enhances the expression of receptors for P5-fimbriae on A549 cells. In summary, RSV infection significantly enhances NTHI attachment to respiratory epithelial cells. P5-fimbria is the critical appendage of NTHI that participates in this attachment. In clinical settings, blocking of the P5-fimbria-mediated attachment of NTHIF+ by passive or active immunity may reduce the morbidity due to NTHI during RSV infection.
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Satola, Sarah W., Brooke Napier, and Monica M. Farley. "Association of IS1016 with the hia Adhesin Gene and Biotypes V and I in Invasive Nontypeable Haemophilus influenzae." Infection and Immunity 76, no. 11 (September 15, 2008): 5221–27. http://dx.doi.org/10.1128/iai.00672-08.

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ABSTRACT A subset of invasive nontypeable Haemophilus influenzae (NTHI) strains has evidence of IS1016, an insertion element associated with division I H. influenzae capsule serotypes. We examined IS1016-positive invasive NTHI isolates collected as part of Active Bacterial Core Surveillance within the Georgia Emerging Infections Program for the presence or absence of hmw1 and hmw2 (two related adhesin genes that are common in NTHI but absent in encapsulated H. influenzae) and hia (homologue of hsf, an encapsulated H. influenzae adhesin gene). Isolates were serotyped using slide agglutination, confirmed as NTHI strains using PCR capsule typing, and biotyped. Two hundred twenty-nine invasive NTHI isolates collected between August 1998 and December 2006 were screened for IS1016; 22/229 (9.6%) were positive. Nineteen of 201 previously identified IS1016-positive invasive NTHI isolates collected between January 1989 and July 1998 were also examined. Forty-one IS1016-positive and 56 randomly selected IS1016-negative invasive NTHI strains were examined. The hia adhesin was present in 39 of 41 (95%) IS1016-positive NTHI strains and 1 of 56 (1.8%) IS1016-negative NTHI strains tested; hmw (hmw1, hmw2, or both) was present in 50 of 56 (89%) IS1016-negative NTHI isolates but in only 5 of 41 (12%; all hmw2) IS1016-positive NTHI isolates. IS1016-positive NTHI strains were more often biotype V (P < 0.001) or biotype I (P = 0.04) than IS1016-negative NTHI strains, which were most often biotype II. Pulsed-field gel electrophoresis revealed the expected genetic diversity of NTHI with some clustering based on IS1016, hmw or hia, and biotypes. A significant association of IS1016 with biotypes V and I and the presence of hia adhesins was found among invasive NTHI. IS1016-positive NTHI strains may represent a unique subset of NTHI strains, with characteristics more closely resembling those of encapsulated H. influenzae.
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Euba, Begoña, Javier Moleres, Cristina Viadas, Montserrat Barberán, Lucía Caballero, María-Jesús Grilló, José Antonio Bengoechea, et al. "Relationship between Azithromycin Susceptibility and Administration Efficacy for Nontypeable Haemophilus influenzae Respiratory Infection." Antimicrobial Agents and Chemotherapy 59, no. 5 (February 23, 2015): 2700–2712. http://dx.doi.org/10.1128/aac.04447-14.

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ABSTRACTNontypeableHaemophilus influenzae(NTHI) is an opportunistic pathogen that is an important cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). COPD is an inflammatory disease of the airways, and exacerbations are acute inflammatory events superimposed on this background of chronic inflammation. Azithromycin (AZM) is a macrolide antibiotic with antibacterial and anti-inflammatory properties and a clinically proven potential for AECOPD prevention and management. Relationships between AZM efficacy and resistance by NTHI and between bactericidal and immunomodulatory effects on NTHI respiratory infection have not been addressed. In this study, we employed two pathogenic NTHI strains with different AZM susceptibilities (NTHI 375 [AZM susceptible] and NTHI 353 [AZM resistant]) to evaluate the prophylactic and therapeutic effects of AZM on the NTHI-host interplay. At the cellular level, AZM was bactericidal toward intracellular NTHI inside alveolar and bronchial epithelia and alveolar macrophages, and it enhanced NTHI phagocytosis by the latter cell type. These effects correlated with the strain MIC of AZM and the antibiotic dose. Additionally, the effect of AZM on NTHI infection was assessed in a mouse model of pulmonary infection. AZM showed both preventive and therapeutic efficacies by lowering NTHI 375 bacterial counts in lungs and bronchoalveolar lavage fluid (BALF) and by reducing histopathological inflammatory lesions in the upper and lower airways of mice. Conversely, AZM did not reduce bacterial loads in animals infected with NTHI 353, in which case a milder anti-inflammatory effect was also observed. Together, the results of this work link the bactericidal and anti-inflammatory effects of AZM and frame the efficacy of this antibiotic against NTHI respiratory infection.
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Juneau, Richard A., Bing Pang, Kristin E. D. Weimer, Chelsie E. Armbruster, and W. Edward Swords. "NontypeableHaemophilus influenzaeInitiates Formation of Neutrophil Extracellular Traps." Infection and Immunity 79, no. 1 (October 18, 2010): 431–38. http://dx.doi.org/10.1128/iai.00660-10.

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ABSTRACTNontypeableHaemophilus influenzae(NTHI) is a leading cause of otitis media infections, which are often chronic and/or recurrent in nature. NTHI and other bacterial species persistin vivowithin biofilms during otitis media and other persistent infections. These biofilms have a significant host component that includes neutrophil extracellular traps (NETs). These NETs do not mediate clearance of NTHI, which survives within NET structures by means of specific subpopulations of lipooligosaccharides on the bacterial surface that are determinants of biofilm formationin vitro. In this study, the ability of NTHI and NTHI components to initiate NET formation was examined using anin vitromodel system. Both viable and nonviable NTHI strains were shown to promote NET formation, as did preparations of bacterial DNA, outer membrane proteins, and lipooligosaccharide (endotoxin). However, only endotoxin from a parental strain of NTHI exhibited equivalent potency in NET formation to that of NTHI. Additional studies showed that NTHI entrapped within NET structures is resistant to both extracellular killing within NETs and phagocytic killing by incoming neutrophils, due to oligosaccharide moieties within the lipooligosaccharides. Thus, we concluded that NTHI elicits NET formation by means of multiple pathogen-associated molecular patterns (most notably endotoxin) and is highly resistant to killing within NET structures. These data support the conclusion that, for NTHI, formation of NET structures may be a persistence determinant by providing a niche within the middle-ear chamber.
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Avadhanula, Vasanthi, Carina A. Rodriguez, Glen C. Ulett, Lauren O. Bakaletz, and Elisabeth E. Adderson. "Nontypeable Haemophilus influenzae Adheres to Intercellular Adhesion Molecule 1 (ICAM-1) on Respiratory Epithelial Cells and Upregulates ICAM-1 Expression." Infection and Immunity 74, no. 2 (February 2006): 830–38. http://dx.doi.org/10.1128/iai.74.2.830-838.2006.

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ABSTRACT Nontypeable Haemophilus influenzae (NTHI) is an important respiratory pathogen. NTHI initiates infection by adhering to the airway epithelium. Here, we report that NTHI interacts with intracellular adhesion molecule 1 (ICAM-1) expressed by respiratory epithelial cells. A fourfold-higher number of NTHI bacteria adhered to Chinese hamster ovary (CHO) cells transfected with human ICAM-1 (CHO-ICAM-1) than to control CHO cells (P ≤ 0.005). Blocking cell surface ICAM-1 with specific antibody reduced the adhesion of NTHI to A549 respiratory epithelial cells by 37% (P = 0.001) and to CHO-ICAM-1 cells by 69% (P = 0.005). Preincubating the bacteria with recombinant ICAM-1 reduced adhesion by 69% (P = 0.003). The adherence to CHO-ICAM-1 cells of NTHI strains deficient in the adhesins P5, P2, HMW1/2, and Hap or expressing a truncated lipooligosaccharide was compared to that of parental strains. Only strain 1128f−, which lacks the outer membrane protein (OMP) P5-homologous adhesin (P5 fimbriae), adhered less well than its parental strain. The numbers of NTHI cells adhering to CHO-ICAM-1 cells were reduced by 67% (P = 0.009) following preincubation with anti-P5 antisera. Furthermore, recombinant ICAM bound to an OMP preparation from strain 1128f+, which expresses P5, but not to that from its P5-deficient mutant, confirming a specific interaction between ICAM-1 and P5 fimbriae. Incubation of respiratory epithelial cells with NTHI increased ICAM-1 expression fourfold (P = 0.001). Adhesion of NTHI to the respiratory epithelium, therefore, upregulates the expression of its own receptor. Blocking interactions between NTHI P5 fimbriae and ICAM-1 may reduce respiratory colonization by NTHI and limit the frequency and severity of NTHI infection.
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Atto, Brianna, Roger Latham, Dale Kunde, David A. Gell, and Stephen Tristram. "In Vitro Anti-NTHi Activity of Haemophilin-Producing Strains of Haemophilus haemolyticus." Pathogens 9, no. 4 (March 25, 2020): 243. http://dx.doi.org/10.3390/pathogens9040243.

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Nontypeable Haemophilus influenzae (NTHi) is a leading causative organism of opportunistic respiratory tract infections. However, there are currently no effective vaccination strategies, and existing treatments are compromised by antibiotic resistance. We previously characterized Haemophilus haemolyticus (Hh) strains capable of producing haemophilin (HPL), a heme-binding protein that restricts NTHi growth by limiting its access to an essential growth factor, heme. Thus, these strains may have utility as a probiotic therapy against NTHi infection by limiting colonization, migration and subsequent infection in susceptible individuals. Here, we assess the preliminary feasibility of this approach by direct in vitro competition assays between NTHi and Hh strains with varying capacity to produce HPL. Subsequent changes in NTHi growth rate and fitness, in conjunction with HPL expression analysis, were employed to assess the NTHi-inhibitory capacity of Hh strains. HPL-producing strains of Hh not only outcompeted NTHi during short-term and extended co-culture, but also demonstrated a growth advantage compared with Hh strains unable to produce the protein. Additionally, HPL expression levels during competition correlated with the NTHi-inhibitory phenotype. HPL-producing strains of Hh demonstrate significant probiotic potential against NTHi colonization in the upper respiratory tract, however, further investigations are warranted to demonstrate a range of other characteristics that would support the eventual development of a probiotic.
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Lewnard, Joseph A., Noga Givon-Lavi, and Ron Dagan. "Interaction With Nontypeable Haemophilus influenzae Alters Progression of Streptococcus pneumoniae From Colonization to Disease in a Site-Specific Manner." Journal of Infectious Diseases 220, no. 8 (June 23, 2019): 1367–76. http://dx.doi.org/10.1093/infdis/jiz312.

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Abstract Background Pneumococci and nontypeable Haemophilus influenzae (NTHi) often cocolonize children. The impact of species interactions on disease risk across the upper respiratory mucosa is not known. Methods We analyzed data from 4104 acute conjunctivitis (AC) cases, 11 767 otitis media (OM) cases, and 1587 nasopharyngeal specimens collected from Israeli children before pneumococcal conjugate vaccine introduction. We compared pneumococcal serotype distributions with NTHi present and absent, and compared single-species and mixed-species rates of serotype-specific progression from colonization to AC and OM. Results Pneumococcal serotypes causing single-species OM (NTHi absent) were less diverse than colonizing serotypes and also less diverse than those causing mixed-species OM; colonizing and OM-causing pneumococcal serotype distributions were more similar to each other with NTHi present than with NTHi absent. In contrast, serotype diversity did not differ appreciably between colonizing and AC-causing pneumococci, regardless of NTHi co-occurrence. The similarity of colonizing and AC-causing pneumococcal serotype distributions was consistent in the presence and absence of NTHi. Differences in rates that pneumococcal serotypes progressed from colonization to disease were reduced in both AC and OM when NTHi was present. Conclusions Interactions with NTHi may alter progression of pneumococcal serotypes to diseases of the upper respiratory mucosa in a site-specific manner.
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Morey, Pau, Victoria Cano, Pau Martí-Lliteras, Antonio López-Gómez, Verónica Regueiro, Carles Saus, José Antonio Bengoechea, and Junkal Garmendia. "Evidence for a non-replicative intracellular stage of nontypable Haemophilus influenzae in epithelial cells." Microbiology 157, no. 1 (January 1, 2011): 234–50. http://dx.doi.org/10.1099/mic.0.040451-0.

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Nontypable Haemophilus influenzae (NTHi) is a Gram-negative, non-capsulated human bacterial pathogen, a major cause of a repertoire of respiratory infections, and intimately associated with persistent lung bacterial colonization in patients suffering from chronic obstructive pulmonary disease (COPD). Despite its medical relevance, relatively little is known about its mechanisms of pathogenicity. In this study, we found that NTHi invades the airway epithelium by a distinct mechanism, requiring microtubule assembly, lipid rafts integrity, and activation of phosphatidylinositol 3-kinase (PI3K) signalling. We found that the majority of intracellular bacteria are located inside an acidic subcellular compartment, in a metabolically active and non-proliferative state. This NTHi-containing vacuole (NTHi-CV) is endowed with late endosome features, co-localizing with LysoTracker, lamp-1, lamp-2, CD63 and Rab7. The NTHi-CV does not acquire Golgi- or autophagy-related markers. These observations were extended to immortalized and primary human airway epithelial cells. By using NTHi clinical isolates expressing different amounts of phosphocholine (PCho), a major modification of NTHi lipooligosaccharide, on their surfaces, and an isogenic lic1BC mutant strain lacking PCho, we showed that PCho is not responsible for NTHi intracellular location. In sum, this study indicates that NTHi can survive inside airway epithelial cells.
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Kotnala, Sudhir, Yerin Kim, Charu Rajput, Hymavathi Reddyvari, Sudhir Bolla, Nathaniel T. Marchetti, Beata Kosmider, Karim Bahmed, and Umadevi S. Sajjan. "Contribution of dipeptidyl peptidase 4 to non-typeable Haemophilus influenzae-induced lung inflammation in COPD." Clinical Science 135, no. 17 (September 1, 2021): 2067–83. http://dx.doi.org/10.1042/cs20210099.

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Abstract Dipeptidyl peptidase 4 (DPP4) expression is increased in the lungs of chronic obstructive pulmonary disease (COPD). DPP4 is known to be associated with inflammation in various organs, including LPS-induced acute lung inflammation. Since non-typeable Haemophilus influenzae (NTHi) causes acute exacerbations in COPD patients, we examined the contribution of DPP4 in NTHi-induced lung inflammation in COPD. Pulmonary macrophages isolated from COPD patients showed higher expression of DPP4 than the macrophages isolated from normal subjects. In response to NTHi infection, COPD, but not normal macrophages show a further increase in the expression of DPP4. COPD macrophages also showed higher expression of IL-1β, and CCL3 responses to NTHi than normal, and treatment with DPP4 inhibitor, diprotin A attenuated this response. To examine the contribution of DPP4 in NTHi-induced lung inflammation, COPD mice were infected with NTHi, treated with diprotin A or PBS intraperitoneally, and examined for DPP4 expression, lung inflammation, and cytokine expression. Mice with COPD phenotype showed increased expression of DPP4, which increased further following NTHi infection. DPP4 expression was primarily observed in the infiltrated inflammatory cells. NTHi-infected COPD mice also showed sustained neutrophilic lung inflammation and expression of CCL3, and this was inhibited by DPP4 inhibitor. These observations indicate that enhanced expression of DPP4 in pulmonary macrophages may contribute to sustained lung inflammation in COPD following NTHi infection. Therefore, inhibition of DPP4 may reduce the severity of NTHi-induced lung inflammation in COPD.
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Craig, Jane E., Angela Nobbs, and Nicola J. High. "The Extracytoplasmic Sigma Factor, ςE, Is Required for Intracellular Survival of Nontypeable Haemophilus influenzae in J774 Macrophages." Infection and Immunity 70, no. 2 (February 2002): 708–15. http://dx.doi.org/10.1128/iai.70.2.708-715.2002.

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ABSTRACT Nontypeable Haemophilus influenzae (NTHi) causes a wide variety of respiratory tract infections in humans. It is capable of invading and surviving in epithelial cells and has also been shown to persist in macrophage-like cell line J774A.1. To determine the molecular mechanisms which enable NTHi to survive in an intracellular environment, differential display reverse transcriptase PCR was used to identify genes which were either induced or upregulated by NTHi residing in macrophages. Using this approach, we identified one transcript which was consistently amplified from intracellular NTHi cDNA. Nucleotide sequence analysis of this product revealed that it spanned the 3′ and 5′ ends of rpoE and rseB, respectively, which form part of the extracytoplasmic stress operon that encodes and regulates expression of alternate sigma factor sigma E (ςE). To confirm that expression of rpoE was upregulated following uptake of NTHi by macrophages, an rpoE-lacZ transcriptional fusion was constructed, and expression of β-galactosidase activity in broth-grown NTHi was compared with expression of β-galactosidase activity in intracellular NTHi. The level of β-galactosidase activity in NTHi 4 h after phagocytosis by macrophages was found to be 100-fold higher than that of broth-grown organisms, suggesting that genes of the ςE regulon may be important for persistence of NTHi in mammalian cells. The hypothesis that ςE plays a role in the intracellular survival of NTHi was subsequently confirmed by the decreased ability of an rpoE insertion mutant to survive in macrophages.
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Dissertations / Theses on the topic "NTHi"

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Foxwell, Alice Ruth, and n/a. "Mechanisms of immunity to nontypeable Haemophilus influenzae in the lung." University of Canberra. Applied Science, 1998. http://erl.canberra.edu.au./public/adt-AUC20060710.142114.

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Pulmonary infection caused by nontypeable Haemophilus influenzae (NTHi) is a significant cause of morbidity and mortality in both industrialised and developing countries. Previous work from this group resulted in the development of a respiratory model in rodents which has precipitated studies into the pathogenesis of infection by NTHi and investigation of the humoral and cellular mechanisms by which the bacteria are cleared from the lung. Comparison of mucosally immunised with non-immunised animals has demonstrated that not only are bacteria cleared more rapidly from the lungs, but there is a more rapid response and resolution of inflammatory factors in the mucosally immunised animals following challenge with NTHi. This inflammatory response is partially regulated by the ability of the mucosally immunised animals to rapidly produce, then control the production of tumour necrosis factor (TNF)-a. The TNF-a is produced by both macrophages and type I pneumocytes in the alveoli and also by the endothelial cells lining the blood vessels in the lungs. Immunocytochemical studies have identified cellular subsets accumulating in the lung at various time points following infection. Marked differences in cellular infiltration into the lung tissue were noted between immunised and non-immunised animals after challenge with NTHi. Immunised animals demonstrated an early influx of macrophages, CD8+ T cells and Y8+ T cells, followed by enhanced expression of the MHC-II marker, cellular infiltration by polymorphonuclear leukocytes and finally an increased number of both B cells and CD4+ T cells. In contrast, non-immunised animals did not demonstrate any proliferation nor extravasation of lymphocytes or increased expression of MHC-II before total bacterial clearance had occurred. Polymorphonuclear leukocyte infiltration occurred in the non-immunised animals, however at a later time than that seen in immunised animals. Challenging rodents to establish persistent infection highlighted the inappropriately aggressive white blood cell response to an initial challenge when bacteria may be masked by other substances, followed by the inability to amplify the polymorphonuclear leukocyte response on repeated challenge with NTHi. This hyporesponsiveness in the macrophage population, shown by lack of detectable TNF-a production, concomitant with low numbers of NTHi resulted in a continuously high number of macrophages in the alveoli and the possibility of increased damage to the lung tissue. The requirement for cell surface TNF-a and CD8+ T cells to enhance the clearance of NTHi from the lungs further strengthens previous in vitro and in vivo findings of the possible significance of cellular invasion as a mechanism of pathogenicity for NTHi. This thesis has contributed to the understanding of both the immune response to and the pathogenicity mechanisms of pulmonary infection with NTHi. Kinetic studies identifying cellular responses and cytokine levels have emphasised the ability of mucosal immunisation to increase the rate of immune response and resolution of inflammation to NTHi infection in the lung. Observations demonstrating a requirement for macrophages and CD8+ T cells in mechanisms associated with enhancing NTHi clearance from the lung will lead to further investigations.
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McGrath, John Francis, and n/a. "Immunomodulation in the context of developing a nontypeable Haemophilus influenzae vaccine." University of Canberra. Health Sciences, 2007. http://erl.canberra.edu.au./public/adt-AUC20070726.152419.

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One of the major challenges of vaccine development is the conservation of immunogenicity and protective efficacy through the stages of design, production, formulation and delivery. The critical issue is that how and in what form an antigen is taken up by antigen presenting cells for proteolytic processing and presentation to the immune system bound to MHC can have dramatic effects on the activation of Th cells to drive clonal responses and induction of immunological memory. Nontypeable Haemophilus influenzae (NTHi) is a pathogenic commensal of the human respiratory tract that causes diseases with enormous socioeoconomic burdens. There is no licensed vaccine, although the potential for vaccination with outer membrane components to reduce the incidence of disease caused by NTHi has recently been demonstrated in clinical trials. The issue of immunomodulation was explored in this thesis in the context of the further evaluation of a leading NTHi vaccine candidate, the outer membrane protein OMP26. The efficacy of recombinant OMP26 (rOMP26) against NTHi challenge has been previously demonstrated in mice, rats and chinchillas. In rats, efficacy was shown to be restricted to the precursor form (containing the signal peptide) and not the mature form of rOMP26. The immunodulatory effects of changes to the rOMP26 structure were further investigated in this thesis. A range of structural variants of rOMP26 were constructed in view of reducing extraneous plasmid-derived sequence from the antigen and to introduce a unique cysteine residue as a potential conjugate site for multivalent vaccine development (Chapter 2). It was demonstrated that minor structural changes to rOMP26 such as the addition, deletion, modification or relative positioning of a single amino acid or bulky group, designed to increase the efficiency of production or introduce (cysteine) conjugation sites, altered the expression of the protein in E. coli and the immunogenicity in Balb/C mice. Furthermore, in contradiction to the published report (El-Adhami et al. 1999) and a new study in rats (Chapter 3), there was no positive effect of the signal peptide in mice, with precursor and mature forms of rOMP26 equally immunogenic (Chapter 2). Following confirmation of the need to retain the signal peptide for the immunogenicity of rOMP26 in rats, a precursor form (rOMP26VTAL) in which the conserved n-region of the signal peptide was deleted, and shown to reduce the efficiency of the cleavage of the signal peptide by signal peptidase during protein overexpression in E. coli (Chapter 3). Not only did this deletion result in an increase the yield and stability of the purified precursor protein, but rOMP26VTAL was highly immunogenic and enhanced the clearance of NTHi from the lungs of challenged rats. The potential for signal peptides to be exploited as an immune-enhancing moiety in a proteinaceous vaccine is discussed. Following the development of rOMP26VTAL as a production optimised variant of rOMP26, the next step was to test the feasibility of rOMP26VTAL as a component of a multivalent vaccine (Chapter 4). Two chimeras were constructed with LB1(f)2,1,3, a trivalent synthetic B-cell epitope from the extracellular loop 3 region of the P5 fimbrin protein of NTHi, positioned at the N- or C-terminus of rOMP26VTAL. The solubility of rOMP26VTAL was affected by the fusion, with both chimera constructs expressed only in the insoluble fraction, thus requiring a denaturing protocol for purification. Although rLB1(f)2,1,3-OMP26VTAL was expressed and purified as a more stable protein and in greater yield than rOMP26VTAL-LB1(f)2,1,3, the relative positioning of the fusion was important and rOMP26VTAL-LB1(f)2,1,3 was significantly more immunogenic in rats than rLB1(f)2,1,3-OMP26VTAL. In addition, rOMP26VTALLB1( f)2,1,3, but not rLB1(f)2,1,3-OMP26VTAL induced a significant degree of bacterial clearance following pulmonary challenge with NTHi, in levels comparable to the highly efficacious rOMP26VTAL construct. In the third part of the thesis, bacterial ghosts were evaluated as a novel mucosal delivery technology for rOMP26VTAL and rOMP26VTAL-LB1(f)2,1,3, (Chapter 5). To mimic the natural presentation of OMP26 and P5 fimbrin antigens on the cell surface of NTHi, an OmpA� sandwich fusion surface display system was developed for the outer membrane expression of the OMP26 constructs in E. coli ghosts. Following gut immunisation, but not intranasal immunisation even when co-administered with the cholera toxin�derived adjuvant CTA1-DD, bacterial ghosts were successful at presenting OMP26VTAL and rOMP26VTAL-LB1(f)2,1,3 to the immune system for the induction of enhanced clearance of NTHi in the rat pulmonary challenge model. Although this study was the first to demonstrate enhanced bacterial clearance induced by heterologous antigens expressed in the outer membrane of bacterial ghosts, future studies with ghosts will require optimisation of the expression levels of the OmpA� fusion proteins possibly to avoid cross-reactive responses related to high doses of ghosts in the inoculum. This thesis presents data that both supports the further evaluation of rOMP26 constructs for clinical trials, and has demonstrated the significant effects of structural changes, method of production and delivery system can have on the immunogenicity of a candidate vaccine. Such knowledge will contribute to and provide some new approaches for enhancing the efficiency of vaccine development against a range of diseases including those caused by NTHi. Major Outcomes: 1. Demonstration that the immunogenicity of rOMP26 antigen constructs is affected by structural modifications and their positioning within the construct, and by the delivery system. 2. Development of rOMP26VTAL, an rOMP26 construct with the KNIAK sequence deletion of the signal peptide n-region. This protein retains the immunogenicity and protective efficacy of rOMP26, but is produced with reduced cleavage of the signal peptide, resulting in higher yields and a stable protein. Lacks extraneous plasmidderived multiple cloning site sequence, and is produced in high yield as a stable protein. 3. Construction of a NTHi rOMP26VTAL-LB1(f)2,1,3 chimera antigen that induced enhanced clearance of NTHi in an acute pulmonary challenge model in rats. 4. Development of an OmpA� surface display system for the expression of rOMP26 antigen constructs in the outer membrane of E. coli/bacterial ghosts 5. Bacterial ghosts were successful as delivery vehicles for rOMP26 candidate vaccine constructs when delivered in the gut.
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Kunthalert, Duangkamol, and n/a. "Immunological and structural characterisation of the nontypeable Haemophilus influenzae vaccine protein OMP26." University of Canberra. Health Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20060406.101830.

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Nontypeable Haemophilus influenzas (NTHi) is recognised as a significant human pathogen causing mild to severe respiratory tract infections. At present, no vaccine is available for prevention of infection caused by this pathogen. Several outer membrane proteins (OMPs) of NTHi and its lipooligosaccharide have been investigated as possible vaccine antigens against NTHi infections. Previous investigations in our laboratory have shown that OMP26 from an NTHi 289 strain was able to significantly enhance pulmonary clearance of NTHi in a rat model in which animals were immunised via intestinal Peyer's patches and then boosted intratracheally (Kyd and Cripps, 1998; El- Adhami et al., 1999). In recent studies, the OMP26, when used as a parenteral immunogen, was also highly effective at inducing immune responses that led to significantly enhanced clearance of the chinchilla nasopharynx (Kyd et al., 2003). These studies indicate significant potential of the OMP26 as a candidate vaccine antigen and warrant further investigations for development of a vaccine against NTHi. This thesis focussed on the immunological and structural characterisation of the NTHi vaccine candidate, OMP26. Peptides of OMP26 were used as tools to localise the immunologically important regions of the OMP26. Two different E. coli expression systems, the GST gene fusion and the 6xHis tagged systems, were employed to construct the OMP26 peptides. It was found in this study that, despite efforts to optimise the system, the GST-fusion protein system failed to produce consistent results for the purification and storage of the OMP26 peptides. In contrast, the 6xHis tagged system exhibited more reliable outcomes in the production of the recombinant OMP26 peptides and the stability of the stored purified peptides. As such, the purified OMP26 peptides from the 6xHis tagged system were chosen to map major regions of immunological significance for the OMP26 protein. The regions of the OMP26 which are involved in the induction of the acquired immune responses have been identified in the present study. Based on the antigen specific lymphocyte proliferation assay, the dominant T cell epitopes for OMP26 were located between amino acid residues 95 and 197 (T3+T4 region). These identified T cell epitopes exhibited the capability of efficient T cell activation, suggesting that the epitopes within the T3+T4 region potentially had the highest affinity for binding to the MHC molecules than did any other OMP26 region. Using two different assay systems, ELISA and BIA, the predominant B cell epitopes of OMP26 were located between amino acid residues 45 and 145 (T2+T3 region). This region was also found to be immunodominant across all animal species tested, and with all immunisation regimens used. Flow cytometry analysis also revealed that these particular epitopes were expressed on the surface of NTHi cells. By integration of the data obtained from these current experimental studies and the computational analysis of the OMP26 sequence, two hypothetical models of the OMP26 were also proposed in this study. The significant outcomes obtained in this thesis provide a better understanding of the specificity of the host immune responses to the OMP26 protein These findings provide great benefit not only for the development of a future NTHi vaccine but for the development of the peptide-based immunodiagnostic reagents as well. These diagnostic reagents will be valuable, in particular, for the evaluation of efficacy of an NTHi vaccine in humans that may include OMP26 or specific conformational structures. Future studies are still required to further define the minimum epitope length required for the B and T cell responses identified in this study. The significance of these responses in immune protection against NTHi infection also requires further investigations. Human immune responses also need to be determined, but this can only be achieved following clinical trial studies.
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Heyl, Kerstin Andrea [Verfasser], Hortense [Akademischer Betreuer] Slevogt, Peter F. [Akademischer Betreuer] Zipfel, and Robert [Akademischer Betreuer] Bals. "Die Bedeutung von Dectin-1 für die durch Nontypeable Haemophilus Influenzae (NTHi) induzierte Immunantwort des humanen Lungenepithels / Kerstin Andrea Heyl. Gutachter: Hortense Slevogt ; Peter F. Zipfel ; Robert Bals." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1052020410/34.

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Santana, Estevan Alexis. "Identification of a Fur-regulated small regulatory RNA in nontypeable Haemophilus influenzae." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1410472201.

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Ng, Seang Khi Preston. "The Role of Distinct Host Glycans in the Evolution of Host Adapted Pathogens." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/365445.

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Glycans are carbohydrate structures coating the cell surface of virtually all nucleated cells of vertebrates. A crucial function of glycans is in cell interaction and recognition, which is constantly exploited by bacteria and viral pathogens as targets for toxins, and as a receptor to aid recognition of and adhesion to host cells. Sialic acids, a 9-carbon compound commonly added as a terminal sugar on glycoconjugates is crucial to both bacteria and viruses causing a successful infection. Bacterial pathogens utilize sialic acids as a component of LOS and capsule, both key virulence factors. The decoration of the bacterial cell surface with sialic acid glycoconjugates has two roles; first, to mimic host glycans to evade the host immune system, second, in reducing the efficiency of complement mediated lysis and opsonophagocytosis. Several key bacterial pathogens including Haemophilus influenzae and Pneumococcus also utilize sialic acids as a carbon source. In viruses, host sialic acids glycoconjugates act as a receptor for viral recognition and adherence to host cells. In the case of influenza A virus, a viral neuraminidase is required to cleave and release newly formed viral particles from infected host cell. This thesis investigates the role of sialic acid glycoconjugates in pathogenesis to increase the understanding of sialic acid biology in human host adapted pathogens. The role sialic acids play in pathogenicity is investigated in the major human pathogens; non-typeable Haemophilus influenzae (NTHi) and Neisseria meningitidis and in human influenza A viral strains.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Institute for Glycomics
Science, Environment, Engineering and Technology
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Fernandes, Maria do Carmo de Alustau. "Caracterização do efeito vasodilatador dos nitratos orgânicos GTN, NTHF, NCOE e BIS-NTHF em artéria e veia isoladas de cordão umbilical humano." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/8853.

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Human umbilical cord vessels (HUCV), often considered biological waste, are good models for evaluation of vasoactive substances. The effect of glyceryl trinitrate (GTN) has been characterized in several animal blood vessels, but this nitrate presents little effect on HUCV. The tetrahydrofurfuryl nitrate (NTHF) and 13-cis-9-octadecanoate acetate nitrate (NCOE) are nitric oxide (NO) donors, whose effect has been characterized in animal vessels. 1,2-bis (tetrahydrofuran-2-yl) ethane-1,2-diildinitrato (BIS-NTHF) is a novel compound (two molecules of NTHF) that has no pharmacological studies. The aim of this study was to implement and standardize the technique involving HUCV, and characterize the effect of these four organic nitrates both in artery (HUA) and vein (HUV) rings isolated from umbilical cord. The standardization of the technique showed that 3g and 3h are, respectively, the ideal voltage and time to experiment with the umbilical vessels, besides the fact that it presents a spontaneous decrease both basal tone as the contractile. The study of nitrates showed that these compounds have relaxed the basal tone of HUCV. All nitrate induced vasorelaxation in both umbilical vessels pre-contracted with serotonin (5-HT), with maximum effects than 90%, and more effectively in relaxing HUA than HUV. In this situation, GTN was the most potent nitrate in causing vasodilation, BIS NTHF presented an intermediate power value, while NCOE and NTHF were less potent in relaxing HUV and HUA, respectively. When HUA rings were pre-contracted with KCl 60 mM, there was an attenuation of vasodilation promoted by nitrates. GTN and the NTHF also showed decreased vasorelaxation in HUV rings contracted with KCl 60 mM, while NCOE and BIS-NTHF have effects similar to the rings pre-contracted with 5 HT. Preincubation of GTN, BIS-NTHF and NTHF attenuated contractions induced by 5-HT in HUA rings. Additionally, GTN and BIS-NTHF also inhibited contraction stimulated by 5-HT in HUV. In contrast, preincubation of NTHF in HUV, and NCOE both in HUV as HUA led to lower inhibition when compared with the other nitrates. GTN, NTHF and BIS-NTHF inhibited the phasic and tonic components of the contraction induced by 5-HT in the absence of extracellular Ca2+. NCOE was more effective to inhibit the tonic contraction. Pre-incubation of 10 μM of ODQ, inhibitor of soluble cyclase guanylyl, attenuated significantly the vasodilator response to GTN, NTHF, NCOE and BIS NTHF was. Preincubation of 10 mM TEA, a blocker of potassium channels, decreased the relaxant response of the four nitrates in HUA, while do not alter the effect in HUV. In view of what has been exposed here, it can be concluded that GTN, NTHF, NCOE and BIS-NTHF cause vasorelaxation of HUCV rings, both in basal tone as contractions induced by 5-HT or KCl. The mechanism of nitrates action in these human vessels involves activation of sCG and channels for potassium; and inhibition of calcium entry, release of stocks of this ion by sarcoplasmic reticulum and ROCK activity.
Vasos umbilicais humano (HUCV), muitas vezes considerado lixo biológico, são bons modelos para avaliação de substâncias vasoativas. O efeito do trinitrato de gliceril (GTN) já foi caracterizado em vários vasos sanguíneos animais, mas em HUCV foi apenas relatado que este nitrato apresenta pouco efeito. O nitrato de tetra-hidrofurfurilo (NTHF) e o 13-nitrato-cis-9-octadecanoato de etila (NCOE) são doadores de óxido nítrico (NO), cujo efeito foi caracterizado em vasos animais. O 1,2-bis(tetrahidrofuran-2-il)etano-1,2-diildinitrato (BIS-NTHF) é um composto inédito (duas moléculas de NTHF) que não possui estudos farmacológicos. O objetivo deste estudo foi implantar e padronizar a técnica envolvendo HUCV, e caracterizar o efeito desses quatro nitratos orgânicos tanto em anéis de artéria (HUA) como veia (HUV) isoladas de cordão. A padronização da técnica mostrou que 3 g e 3h são, respectivamente, a tensão e tempo ideais para experimentos com os vasos umbilicais, além do fato de que estes apresentam uma queda espontânea tanto do tônus basal como do contrátil. O estudo com os nitratos mostrou que esses compostos relaxaram o tônus basal de HUCV. Todos os nitratos induziram vasorrelaxamento, em ambos os vasos umbilicais pré-contraídos com serotonina (5-HT), com efeitos máximos superiores a 90%, e com maior eficácia em relaxar HUA do que HUV. Nesta situação, GTN foi o nitrato mais potente em causar vasodilatação, BIS-NTHF apresentou um valor de potência intermediário, enquanto que NCOE e NTHF foram os menos potentes em relaxar HUV e HUA, respectivamente. Quando os anéis de HUA foram pré-contraídos com KCl 60 mM, houve uma atenuação da vasodilatação promovida pelos nitratos. GTN e NTHF também apresentaram o vasorrelaxamento diminuído nos anéis de HUV pré-contraídos com KCl 60 mM, enquanto NCOE e BIS-NTHF tiveram seus efeitos de forma semelhante aos anéis pré-contraídos com 5-HT. A pré-incubação de GTN, NTHF e BIS-NTHF atenuou as contrações induzidas por 5-HT, em anéis de HUA. Adicionalmente, GTN e BIS-NTHF também inibiram a contração estimulada por 5-HT em HUV. Em contrapartida, a pré-incubação de NTHF, em HUV, e de NCOE, tanto em HUV como em HUA, levaram à inibição menor, quando comparados aos outros nitratos. GTN, NTHF e BIS-NTHF inibiram o componente fásico e tônico da contração induzida por 5-HT, na ausência do Ca2+ extracelular. NCOE, por sua vez, foi mais eficaz em inibir a contração tônica. A pré-incubação de 10 μM de ODQ, inibidor da ciclase de guanilil solúvel, fez com que a resposta vasodilatadora de GTN, NTHF, NCOE e BIS-NTHF fosse atenuada de maneira significativa. A pré-incubação de 10 mM de TEA, um bloqueador de canais para potássio, em HUA diminuiu a resposta relaxante dos quatro nitratos, não alterando o efeito em HUV. Diante do exposto, pode-se concluir que os nitratos orgânicos GTN, NTHF, NCOE e BIS-NTHF causam vasorrelaxamento de anéis de HUCV, tanto no tônus basal quanto de contrações induzidas por 5-HT ou KCl. O mecanismo de ação dos nitratos nestes vasos humanos envolve ativação da sGC e de canais para potássio; e inibição da entrada de cálcio, liberação dos estoques deste íon do retículo sarcoplasmático e da atividade da ROCK.
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Ntho, Mokgadi Gloria. "An educational-psychological investigation of the attitude of Black learners to HIV/AIDS / Mokgadi Gloria Ntho." Thesis, North-West University, 2005. http://hdl.handle.net/10394/2361.

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Furtado, Fabiola Fialho. "Efeitos cardiovasculares induzidos por um novo doador de óxido nítrico, o nitrato tetrahidrofurfurílico (NTHF), em ratos." Universidade Federal da Paraí­ba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/6808.

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Previous studies have show that the organic nitrate tetrahydrofurfuryl (NTHF) induces vasorelaxation in mesenteric artery rings with involvement of the NO-sGC-PKG pathway. This study evaluated the action of NTHF on cardiovascular parameters in spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats, investigating: the nitric oxide (NO) release, acute toxicity, the NTHF effect on blood pressure and heart rate, its vasorelaxant effect and its ability to induce tolerance. NTHF increased NO levels in rat aortic smooth muscle cells (SMC) and cardiomyocites. In acute toxicity studies, a high single dose from NTHF showed low toxicity. In normotensive animals, NTHF induced hypotension after oral administration of NTHF, and bradycardic and hypotensive effects following administration of this nitrate. These results were similar that found using nitroglycerine (NTG). In addition, these effects were not altered by pretreatment with hexamethonium, a ganglionic blocker. However the treatment with methylene blue, a sGC inhibitor, promoted attenuation of both hypotensive and bradycardic effects, suggesting the involvement of the sGC pathway in these effects. In mesenteric artery rings from SHR and WKY rats precontracted with phenylephrine, NTHF induced concentration dependent vasodilatation in both intact and removed endothelium. This result suggests that the vasorelaxant effect is an endothelium derived relaxation factors (EDRFs) independent mechanism. Furthermore, in the presence of NO° scavenging (PTIO) or ODQ, a sGC inhibitor, the vasorelaxation induced by NTHF was decreased, indicating the involvement of NO-sGC pathway in this response in both SHR and WKY. In the presence of cyanamide, an aldehyde dehydrogenase (mtALDH) inhibitor, the vasorelaxant effect was diminished, suggesting that NTHF is metabolized by this enzyme. After exposure to depolarizing agent KCl, the nitrate effect was significantly attenuated, a characteristic of substances which acts by K+ channels activation. This effect was confirmed after using tetraetylamonium (TEA), a K+ channels inhibitor. In normotensive rats treated with NTHF, the acute administration of NTHF promoted bradycardia and hypotension were are not changed in relation to which those observed in vehicle-treated animals, suggesting that organic nitrate did not induce in vivo tolerance. In vitro tolerance was evaluated in both mesenteric artery rings from animals pretreated with NTHF as well as rings previously exposed to isolated concentrations of NTHF. The vasorelaxant effect was not modified by pretreatment or exposure to NTHF, unlike that observed with NTG. In rings treated with NTG, the effect induced by NTHF was not modified, indicating that NTHF did not promote in vitro tolerance. The results demonstrated that NTHF promoted hypotensive and bradycardic effects in both SHR and WKY rats, with involvement of sGC enzyme; NTHF induced a vasorelaxant effect with participation of NO-sGC-PKG pathway and K+ channels. These effects seem to be mediated by NO release from cardiomyocites and SMC. Finally this study will help to advance the field towards clinical trials, since NTHF caused low toxicity and this nitrate was devoid of in vivo and in vitro tolerance.
Estudos anteriores demonstraram que o nitrato orgânico tetra-hidrofurfurílico (NTHF), promoveu efeito vasorrelaxante em artéria mesentérica de ratos normotensos, com envolvimento da via NO-sGC-PKG. O objetivo deste trabalho foi avaliar os efeitos cardiovasculares induzidos pelo NTHF em ratos espontaneamente hipertensos (SHR) e normotensos Wistar Kyoto (WKY), investigando: a liberação de óxido nítrico (NO), a toxicidade aguda, o efeito do NTHF sobre pressão arterial (PA) e frequência cardíaca (FC), o efeito vasodilatador desse composto, além de sua capacidade em induzir tolerância. Em células musculares lisas vasculares (CMLV) de aorta de rato e cardiomiócitos, NTHF promoveu aumento dos níveis de NO. Na avaliação da toxicidade aguda, NTHF foi administrado por via oral numa dose elevada, e nestas condições o nitrato orgânico apresentou baixa toxicidade. Em animais normotensos, NTHF promoveu hipotensão quando administrado por via oral e efeito hipotensor e bradicárdico após a administração intravenosa, semelhante ao observado pelo gliceril trinitrato (GTN). Este efeito não foi alterado pelo prétratamento com hexametônio, um bloqueador nicotínico ganglionar. Porém, o tratamento com azul de metileno, inibidor da enzima ciclase de guanilil solúvel (sGC), promoveu diminuição da resposta, indicando a participação da sGC nos efeitos hipotensor e bradicárdico. Em animais WKY e SHR NTHF promoveu efeito hipotensor e bradicárdico. Em anéis de artéria mesentérica de ratos SHR e WKY, pré-contraídos com fenilefrina, NTHF promoveu vasodilatação concentraçãodependente, com endotélio vascular intacto ou removido, sugerindo um efeito independente da liberação dos fatores relaxantes derivados do endotélio (EDRFs). Na presença do sequestrador de NO radicalar (PTIO) ou do inibidor seletivo da sGC (ODQ), o efeito vasorrelaxante do NTHF foi atenuado, indicando a participação da via NO-sGC tanto em SHR quanto WKY. Na presença de cianamida, um inibidor da enzima aldeído desidrogenase mitocondrial (mtALDH), o efeito vasorrelaxante foi atenuado, indicando que o nitrato é metabolizado por esta enzima. Após a exposição ao agente despolarizante KCl e após adição de tetraetilamônio (TEA), inibidor de canais para K+, o efeito do NTHF foi diminuído. Em animais normotensos prétratados com NTHF, a administração aguda de NTHF hipotensão e bradicardia, comparáveis às observadas no grupo controle, sugerindo que o NTHF não induz tolerância in vivo. A tolerância in vitro foi avaliada em artéria mesentérica de animais tratados previamente com NTHF, quando previamente expostos a concentrações isoladas do nitrato. O efeito vasorrelaxante não foi modificado pelo tratamento ou exposição prévia ao NTHF. Efeito contrário ao obtido com GTN. Em anéis prétratados com GTN, o efeito induzido pelo NTHF não foi modificado, sugerindo que o nitrato em estudo não promove tolerância in vitro. Os resultados demonstram que o NTHF promoveu efeito hipotensor e bradicárdico em animais normotensos e hipertensos, com envolvimento da enzima sGC; apresentou efeito vasorrelaxante, com participação da via NO-sGC-PKG e também de canais para K+. Esses efeitos parecem ser mediados por meio da liberação de NO tanto em CMLV quanto em cardiomiócitos. Por fim, NTHF evidencia um potencial clínico por apresentar baixa toxicidade e não induzir tolerância in vivo e in vitro
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Martin, Florence. "Etude des distributions en masse, charge nucléaire et énergie cinétique des produits de fission de l'233U(nth,f) et du 241Pu(nth,f) mesurées auprès du spectromètre de masse Lohengrin (ILL)." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENI098/document.

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Les rendements des produits de fission font partie des données nucléaires sur lesquellesreposent les simulations neutroniques. L’objectif de cette thèse est d’apporter de nouvellesmesures de rendements de fission de deux noyaux fissiles : le 241Pu et l’233U. Ces noyauxappartiennent respectivement au cycle du combustible de l’uranium et à celui du thorium.Ces mesures ont été réalisées auprès du spectromètre de masse Lohengrin de l’InstitutLaue Langevin (ILL) à Grenoble. Le spectromètre est combiné avec une chambre d’ionisationpour mesurer les rendements en masse de l’233U et du 241Pu et avec un dispositif despectrométrie gamma pour déterminer les rendements isotopiques de l’233U.Une nouvelle procédure d’analyse innovante a été mise en place dans le but de maîtriserles systématiques et de réduire les biais expérimentaux. La matrice de variance-covarianceassociée à nos mesures de rendements a ainsi pu être calculée pour la première fois
Fission product yields are significant nuclear data for neutronic simulations. The purposeof this work is to improve fission yield knowledge for two fissile nuclei : 241Pu and 233U. Thoseare respectively involved in the uranium and thorium nuclear fuel cycle.The measurements are performed at the Lohengrin mass spectrometer of the InstitutLaue-Langevin (ILL) located in Grenoble. The spectrometer is combined with an ionizationchamber to measure mass yields of 241Pu and 233U and with a gamma spectrometry set-upto determine isotopic yields of 233U.A new analysis method of experimental data has been developed in order to controlsystematics and to reduce experimental biases. For the first time, the experimental variancecovariancematrix of our measured fission yields could be deduced
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Books on the topic "NTHi"

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Sidney, Sheldon. Thiên thsan ntoi giuan. Hà Nuoi: NXB Lao đuong, 1999.

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Steve, Moore. The indescribable Nth. [Santa Monica, Calif: Hot Press], 1992.

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Motho ke ntho e jwang? Johannesburg: Centaur Publications, 1994.

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Lãn, Đại. Các phi tsan ntoi loạn. TP. Biên Hòa, Đsong Nai: NXB Ttong hvop Đsong Nai, 2006.

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Breton, Guy. Cuuoc đxoi nhzung ngưxoi ntoi tireng. Hà Nuoi: NXB Thanh niên, 2004.

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Phạm, Thị Quang Ninh. Cùng nhau trôi ntoi: Hsoi ký. California: Viuet Đạo, 1999.

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Michael, Shapiro. 100 ngưxoi Do Thái ntoi tireng. Hà Nuoi: NXB Lao đuong, 2003.

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Xizang Zizhiqu wen wu guan li ju., ed. Tuo lin si: Ntho-ling monastery. Beijing: Zhongguo da bai ke quan shu chu ban she, 2001.

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Trân, Thu. Yêu và ntoi loạn: Titeu thuyret. [Hà Nuoi]: Nhà xurat bkan Công an nhân dân, 2007.

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Hoàng, Quroc Hkai. Thăng Long ntoi giuan: Titeu thuyret lịch syu. Hà Nuoi: NXB Phụ nzu, 2004.

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Book chapters on the topic "NTHi"

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Wessler, Heinz Werner, and Rahul Peter Das. "Nth-Literatur." In Kindlers Literatur Lexikon (KLL), 1–3. Stuttgart: J.B. Metzler, 2020. http://dx.doi.org/10.1007/978-3-476-05728-0_22744-1.

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Fincher, Sally. "Writing Your nth Program." In Studying Programming, 133–48. London: Macmillan Education UK, 2006. http://dx.doi.org/10.1007/978-0-230-20845-2_11.

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Xu, Xi Frank. "Nth-order variational bounds." In Multiscale Theory of Composites and Random Media, 59–110. Boca Raton : Taylor & Francis, a CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa, plc, [2019]: CRC Press, 2018. http://dx.doi.org/10.1201/9780429470653-4.

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Bertram, Albrecht. "Nth-Order Gradient Fluids." In Compendium on Gradient Materials, 262–74. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-04500-4_9.

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Hyers, Donald H., George Isac, and Themistocles M. Rassias. "Functions with Bounded nth Differences." In Stability of Functional Equations in Several Variables, 155–65. Boston, MA: Birkhäuser Boston, 1998. http://dx.doi.org/10.1007/978-1-4612-1790-9_8.

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Davis, Philip J., and William G. Chinn. "Explorers of the Nth Dimension." In 3.1416 And All That, 101–7. Boston, MA: Birkhäuser Boston, 1985. http://dx.doi.org/10.1007/978-1-4615-8519-0_14.

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Whitney, Hassler. "On functions with bounded nth differences." In Hassler Whitney Collected Papers, 407–35. Boston, MA: Birkhäuser Boston, 1992. http://dx.doi.org/10.1007/978-1-4612-2972-8_28.

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Lubinsky, Doron S., and Edward B. Saff. "Nth root asymptotics for extremal polynomials." In Strong Asymptotics for Extremal Polynomials Associated with Weights on ℝ, 73–79. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/bfb0082423.

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Cao, Xi-Ren. "The Nth-Bias and Blackwell Optimality." In SpringerBriefs in Electrical and Computer Engineering, 79–108. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-56678-4_5.

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Whitney, Hassler. "On Bounded Functions with Bounded nth Differences." In Hassler Whitney Collected Papers, 453–54. Boston, MA: Birkhäuser Boston, 1992. http://dx.doi.org/10.1007/978-1-4612-2972-8_30.

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Conference papers on the topic "NTHi"

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Desai, Himanshu, Catherine Wrona, Timothy F. Murphy, and Sanjay Sethi. "Mechanisms Of Decline In Serum Bactericidal Activity For Nontypeable Haemophilus Influenzae (NTHI) In COPD Patients Chronically Colonized With NTHI." In American Thoracic Society 2010 International Conference, May 14-19, 2010 • New Orleans. American Thoracic Society, 2010. http://dx.doi.org/10.1164/ajrccm-conference.2010.181.1_meetingabstracts.a2911.

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Ackland, Jodie, Ashley Heinson, David Cleary, Myron Christodoulides, Tom Wilkinson, and Karl Staples. "Dual RNASeq unveils NTHi-macrophage transcriptomic changes during intracellular persistence." In ERS International Congress 2020 abstracts. European Respiratory Society, 2020. http://dx.doi.org/10.1183/13993003.congress-2020.2323.

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Staples, Karl J., Stephen Taylor, Steve Thomas, Kristoffer Ostridge, Alice Richardson, Andrew C. Tuck, Stuart C. Clarke, Andrew Gorringe, and Tom M. A. Wilkinson. "Increased total, secretory and NTHi-specific IgA in the COPD airway." In Annual Congress 2015. European Respiratory Society, 2015. http://dx.doi.org/10.1183/13993003.congress-2015.pa567.

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Wallington, Joshua, Anthony P. Williams, Karl J. Staples, and Tom M. A. Wilkinson. "Cytotoxic responses of mucosal-associated Invariant T cells to NTHi infection." In ERS International Congress 2016 abstracts. European Respiratory Society, 2016. http://dx.doi.org/10.1183/13993003.congress-2016.pa2621.

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Ackland, Jodie, Ashley Heinson, David Cleary, Myron Christodoulides, Tom Wilkinson, and Karl Staples. "NTHi-IAV coinfection of macrophages alters infection outcomes and inflammatory responses." In ERS Lung Science Conference 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/23120541.lsc-2022.76.

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Ackland, Jodie, David Cleary, Myron Christodoulides, Tom Wilkinson, and Karl Staples. "Strain-dependent effects of Nontypeable Haemophilus influenzae (NTHi) on human macrophage function." In Abstracts from the 17th ERS Lung Science Conference: ‘Mechanisms of Acute Exacerbation of Respiratory Disease’. European Respiratory Society, 2019. http://dx.doi.org/10.1183/23120541.lungscienceconference-2019.pp135.

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Wallington, Joshua, Richard McKendry, Anthony Williams, Karl J. Staples, and Tom Wilkinson. "LSC Abstract – Monocyte-derived macrophages upregulate surface MR1 in response to NTHi." In Annual Congress 2015. European Respiratory Society, 2015. http://dx.doi.org/10.1183/13993003.congress-2015.pa2659.

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Ackland, Jodie, Karen Osman, C. Mirella Spalluto, David W. Cleary, Myron Christodoulides, Tom Wilkinson, and Karl J. Staples. "Macrophage inflammatory responses to Non-typeable Haemophilus influenzae (NTHi) are strain-dependent." In ERS International Congress 2019 abstracts. European Respiratory Society, 2019. http://dx.doi.org/10.1183/13993003.congress-2019.pa5440.

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Long, Y., S. Morgan, P. Klenerman, and T. Hinks. "Innate immunity plays an important role during NTHI and RV sequential infection." In ERS International Congress 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/13993003.congress-2022.lsc-0041.

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Long, Yuqing, Sophie Morgan, Paul Klenerman, and Timothy Hinks. "Innate immunity plays an important role during NTHI and RV sequential infection." In ERS Lung Science Conference 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/23120541.lsc-2022.41.

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Reports on the topic "NTHi"

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Liepman, James M. C(nth) I(nth) xyz, TACS, and Air Battle Management: The Search for Operational Doctrine. Fort Belvoir, VA: Defense Technical Information Center, June 1997. http://dx.doi.org/10.21236/ada328102.

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Stockton, Emma, ed. Transport Canada's Northern Transportation Adaptation Initiative (NTAI) 2011-2021. Carleton University, 2021. http://dx.doi.org/10.52381/ntai.2021.

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Burn, Christopher, Jennifer Humphries, Trevor Andersen, Astrid Schetselaar, and Patrick Jardine. Compendium of Permafrost Reports: Northern Transportation Adaptation Initiative (NTAI) 2011-2021. Edited by Emma Stockton. Carleton University, 2021. http://dx.doi.org/10.52381/cpr.ntai.2021.

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Younes, W., and D. Gogny. Microscopic Calculation of Fission Fragment Energies for the 239Pu(nth,f) Reaction. Office of Scientific and Technical Information (OSTI), October 2011. http://dx.doi.org/10.2172/1037849.

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O'Connor, Megan. CRADA Final Report: CRADA Number NFE-18-07313 with Nth Cycle, Inc. Office of Scientific and Technical Information (OSTI), September 2022. http://dx.doi.org/10.2172/1888912.

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Boldon, Lauren M., and Piyush Sabharwall. Small modular reactor: First-of-a-Kind (FOAK) and Nth-of-a-Kind (NOAK) Economic Analysis. Office of Scientific and Technical Information (OSTI), August 2014. http://dx.doi.org/10.2172/1167545.

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Lopez, G. Constant of motion for a one-dimensional and nth-order autonomous system and its relation to the Lagrangian and Hamiltonian. Office of Scientific and Technical Information (OSTI), December 1993. http://dx.doi.org/10.2172/71708.

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Cerón, Lissette, Mishelle Pacheco, Bolivar Delgado, and Wilson Bravo. Therapies for bruxism in dentistry: A systematic review protocol. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, October 2021. http://dx.doi.org/10.37766/inplasy2021.10.0080.

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Abstract:
Review question / Objective: The aim of this study is to evaluate the methodological quality of the literature and the risk of bias used in systematic reviews of therapies for bruxism in dentistry, applying the Amstar II qualitative guide and to answer the following question: What do we know so far about the different treatments applied for bruxism and their effectiveness, as well as what is the overall confidence of the systematic reviews evaluating this topic? Condition being studied: There is an ongoing debate about the causal factors associated with patients diagnosed with bruxism and thus various treatment approaches, so according to the available scientific evidence there is no consensus on which is the most effective. (4) (8) (10). According to several studies, occlusal splints do not currently have a scientifically proven efficacy for the management of bruxism, because they lack randomized controlled clinical studies, and should therefore be considered as a limited treatment modality, since the effect of the splints does not seem to address the cause of bruxism and serves mainly for the management of the signs and symptoms of this disorder (11) (12). Alternative therapies such as relaxation and biofeedback have been proposed for bruxism, especially in cases of daytime bruxism, which are more related to stress and anxiety. (13). There are also studies that support the use of the NTI-tssa device can be used successfully, however, it may present side effects if necessary checks and readjustments are not performed (14). Some medications can be used to decrease bruxing episodes, but some pharmacological treatments may not be safe if used for prolonged periods of time, considering the inherent side effects or risks of dependence (15).
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