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1.
J Laryngol Otol ; 136(6): 520-526, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35403581

ABSTRACT

OBJECTIVE: There is limited understanding of treatment pathways for paediatric sleep-disordered breathing. This study explored current UK pathways and what is important to well-being for parents and children. METHOD: The study comprised in-depth qualitative interviews (n = 22) with parents of children (2-9 years) with symptoms of sleep-disordered breathing referred to a regional ENT clinic (n = 11), general practitioners who might refer these children to ENT (n = 5) and hospital doctors involved in treating these children (n = 6). Interviews were audio recorded, transcribed verbatim, anonymised and analysed thematically. RESULTS: General practitioners rarely identify seeing children with sleep-disordered breathing; conversely hospital doctors identify unsuspected issues. Parents are worried their child will stop breathing, but routes to referral and diagnosis are not straightforward. Modern technology can aid investigation and diagnosis. Patient weight is an issue for general practitioners and hospital doctors. Adenotonsillectomy is the treatment of choice, and information on paediatric sleep-disordered breathing is needed. CONCLUSION: Guidelines for the management of paediatric sleep-disordered breathing are needed.


Subject(s)
Sleep Apnea Syndromes , Tonsillectomy , Adenoidectomy , Child , Humans , Parents , Sleep Apnea Syndromes/surgery , Sleep Apnea Syndromes/therapy , United Kingdom
2.
BMC Health Serv Res ; 18(1): 337, 2018 05 08.
Article in English | MEDLINE | ID: mdl-29739396

ABSTRACT

BACKGROUND: For young people with long-term conditions, transition from child to adult-oriented health services is a critical period which, if not managed well, may lead to poor outcomes. There are features of transition services which guidance and research suggest improve outcomes. We studied nine such features, calling them 'proposed beneficial features': age-banded clinic; meet adult team before transfer; promotion of health self-efficacy; written transition plan; appropriate parent involvement; key worker; coordinated team; holistic life-skills training; transition manager for clinical team. We aimed to describe the extent to which service providers offer these nine features, and to compare this with young people's reported experience of them. METHODS: A longitudinal, mixed methods study followed 374 young people as their care moved from child to adult health services. Participants had type 1 diabetes, cerebral palsy or autism spectrum disorder with additional mental health difficulties. Data are reported from the first two visits, one year apart. RESULTS: Three hundred four (81.3%) of the young people took part in the second visit (128 with diabetes, 91 with autism, 85 with cerebral palsy). Overall, the nine proposed beneficial features of transition services were poorly provided. Fewer than half of services stated they provided an age-banded clinic, written transition plan, transition manager for clinical team, a protocol for promotion of health self-efficacy, or holistic life-skills training. To varying degrees, young people reported that they had not experienced the features which services said they provided. For instance, the agreement for written transition plan, holistic life-skills training and key worker, was 30, 43 and 49% respectively. Agreement was better for appropriate parent involvement, age-banded clinic, promotion of health self-efficacy and coordinated team at 77, 77, 80 and 69% respectively. Variation in the meaning of the features as experienced by young people and families was evident from qualitative interviews and observations. CONCLUSIONS: UK services provide only some of the nine proposed beneficial features for supporting healthcare transition of young people with long term conditions. Observational studies or trials which examine the influence of features of transition services on outcomes should ensure that the experiences of young people and families are captured, and not rely on service specifications.


Subject(s)
Autism Spectrum Disorder/therapy , Cerebral Palsy/therapy , Diabetes Mellitus, Type 1/therapy , Patient Satisfaction , Quality of Health Care , Transition to Adult Care , Adolescent , Autism Spectrum Disorder/psychology , Female , Humans , Longitudinal Studies , Male , Transition to Adult Care/standards , United Kingdom , Young Adult
3.
Clin Exp Allergy ; 48(4): 445-451, 2018 04.
Article in English | MEDLINE | ID: mdl-29423947

ABSTRACT

BACKGROUND: CCR3 is the cognate receptor for major human eosinophil chemoattractants from the eotaxin family of proteins that are elevated in asthma and correlate with disease severity. OBJECTIVE: This proof-of-mechanism study examined the effect of AXP1275, an oral, small-molecule inhibitor of CCR3, on airway responses to inhaled allergen challenge. METHODS: Twenty-one subjects with mild atopic asthma and documented early and late asthmatic responses to an inhaled aeroallergen completed a randomized double-blind cross-over study to compare early and late allergen-induced asthmatic responses, methacholine PC20 , blood and sputum eosinophils and exhaled nitric oxide after 2 weeks of treatment with once-daily doses of AXP1275 (50 mg) or placebo. RESULTS: There was a significant increase in methacholine PC20 after 12 days of AXP1275 treatment compared to placebo (increase of 0.92 doubling doses versus 0.17 doubling doses, P = .01), but this protection was lost post-allergen challenge. There was no effect of AXP1275 on allergen-induced late asthmatic responses, or eosinophils in blood and sputum. The early asthmatic response and exhaled nitric oxide levels were slightly lower with AXP1275, but this did not reach statistical significance. The number of subjects who experienced treatment-emergent adverse events while receiving AXP1275 was comparable placebo. CONCLUSIONS & CLINICAL RELEVANCE: AXP1275 50 mg administered daily was safe and well tolerated, and there was no difference in the type, severity or frequency of treatment-emergent adverse events in subjects while receiving AXP1275 compared to placebo. AXP1275 increased the methacholine PC20 ; however, the low and variable exposure to APX1275 over a short treatment period may have contributed to poor efficacy on other outcomes.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Organic Chemicals/therapeutic use , Receptors, CCR3/antagonists & inhibitors , Adult , Allergens/adverse effects , Allergens/immunology , Bronchial Provocation Tests , Cross-Over Studies , Double-Blind Method , Female , Humans , Male
6.
Clin Exp Allergy ; 41(12): 1740-6, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21762225

ABSTRACT

BACKGROUND: TPI ASM8 contains two modified phosphorothioate antisense oligonucleotides (AON), one targeting the common beta chain (ßc) of the IL-3/IL-5/GM-CSF receptors and the other targeting the chemokine receptor CCR3. Inhalation of TPI ASM8 significantly improves lung function and sputum eosinophilia after allergen inhalation challenge in asthmatics. OBJECTIVE: This study assessed whether TPI ASM8 reduces airway levels of haemopoietic progenitor cells. METHODS: This open-label study was conducted in 14 stable, allergic mild asthmatic subjects with early- and late-phase allergen-induced bronchoconstriction. Subjects underwent allergen challenges after 4-day treatment with placebo, 4 mg b.i.d. and 8 mg o.d. of TPI ASM8. Sputum was induced before, 7 and 24 h after allergen challenges for progenitor measurements. Treatments were separated by 2-3 weeks. RESULTS: TPI ASM8 reduced allergen-induced sputum eosinophils, and the early and late asthmatic responses (P<0.05). TPI ASM8 also reduced the number of CD34(+) CCR3(+) cells (P=0.004) and CD34(+) IL-5Rα(+) cells (P=0.016), and the proportion of CD34(+) cells expressing IL-5Rα (P=0.036). CONCLUSIONS AND CLINICAL RELEVANCE: TPI ASM8 was safe and well tolerated. The results of this study demonstrate blocking of CCR3 and ßc expression by TPI ASM8 significantly inhibits the accumulation of eosinophils and eosinophil progenitors in the airways after allergen challenge. Inhibition of airway progenitor cell accumulation presents a novel therapeutic target.


Subject(s)
Allergens/immunology , Asthma/drug therapy , Asthma/immunology , Eosinophils/immunology , Granulocyte Precursor Cells/immunology , Oligonucleotides, Antisense/therapeutic use , Phosphorothioate Oligonucleotides/therapeutic use , Adult , Allergens/administration & dosage , Antigens, CD34/metabolism , Bronchial Provocation Tests , Eosinophils/metabolism , Female , Granulocyte Precursor Cells/drug effects , Granulocyte Precursor Cells/metabolism , Humans , Immunophenotyping , Male , Middle Aged , Oligonucleotides, Antisense/adverse effects , Phosphorothioate Oligonucleotides/adverse effects , Sputum/cytology , Sputum/immunology , Young Adult
7.
Clin Exp Allergy ; 41(8): 1084-90, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21631611

ABSTRACT

BACKGROUND: Smoking asthmatics experience more severe symptoms, require more rescue medication and have more asthma-related hospitalizations than non-smoking asthmatics. However, studies in mice suggest that mainstream cigarette smoke may reduce airway inflammation and may attenuate airway hyperresponsiveness. A comparison of allergen-induced airway inflammatory responses of smoking and non-smoking atopic asthmatics has not been examined previously. OBJECTIVES: To determine whether allergen-induced airway responses and inflammatory profiles are attenuated in smoking when compared with non-smoking mild allergic asthmatic subjects. METHODS: Allergen inhalation challenges were performed in 13 smoking and 19 non-smoking mild allergic asthmatic subjects. The forced expired volume in 1 s (FEV(1) ) was measured up to 7 h after allergen inhalation. Methacholine airway responsiveness was measured before and at 24 h after allergen and sputum was induced before and at 7 and 24 h after allergen. RESULTS: Both the smoking and non-smoking groups developed similar allergen-induced falls in FEV(1) during the early and late asthmatic responses and similar increases in allergen-induced airway eosinophils. The mean maximum fall in FEV(1) during the late response was 16.3 ± 4.3% in non-smokers and 12.9 ± 7.2% in smokers. The smoking asthmatics, however, did not develop allergen-induced methacholine airway hyperresponsiveness, whereas the non-smoking controls developed a 1.18 doubling dose shift in methacholine PC(20) (P < 0.05). CONCLUSIONS AND CLINICAL RELEVANCE: Mild allergic asthmatic subjects, who were current smokers with a mean 6-year pack history, develop allergen-induced eosinophilic airway inflammation and late responses, similar in magnitude to non-smoking asthmatics, but do not develop methacholine airway hyperresponsiveness associated with the allergen-induced airway eosinophilia.


Subject(s)
Allergens/adverse effects , Asthma/pathology , Methacholine Chloride/adverse effects , Smoking , Administration, Inhalation , Adolescent , Adult , Allergens/administration & dosage , Asthma/immunology , Cotinine/urine , Humans , Methacholine Chloride/administration & dosage , Middle Aged , Sputum/cytology , Sputum/immunology , Young Adult
8.
Allergy ; 66(8): 1075-80, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21447082

ABSTRACT

BACKGROUND: Allergen inhalation causes early and late bronchoconstrictor responses, airway hyperresponsiveness and airway inflammation in allergic asthmatics. The role of airway inflammatory cells in causing allergen-induced bronchoconstriction and airway hyperresponsiveness is controversial. The objective of this study was to examine the relationships between allergen-induced increases in airway inflammatory cells, early and late bronchoconstrictor responses and methacholine airway hyperresponsiveness. METHODS: Allergen inhalation challenge was conducted in 50 allergic asthmatics. Changes in the forced expired volume in 1 s (FEV(1%) ) were followed for 7 h, induced sputum was obtained at 7 and 24 h, and the provocative concentration of methacholine causing a 20% fall in FEV(1) (MCh PC(20) ) was measured at 24 h. RESULTS: There was a significant negative correlation between the baseline methacholine PC(20) and baseline sputum eosinophils (r = -0.512, P = 0.0001). Allergen-induced changes in methacholine PC(20) were also significantly negatively correlated to allergen-induced change in sputum eosinophils at 24 h (r = -0.434, P = 0.002), but not to changes in any other inflammatory cells. There were no significant correlations between sputum eosinophils or other inflammatory cells and the allergen-induced early or late asthmatic responses. CONCLUSION: Allergen-induced increases in airway eosinophils in asthmatic dual responders may contribute to allergen-induced changes in methacholine PC(20) , but not the late asthmatic responses.


Subject(s)
Asthma/pathology , Inflammation/pathology , Sputum/immunology , Allergens/pharmacology , Bronchoconstrictor Agents , Eosinophils/immunology , Humans , Methacholine Chloride/pharmacology
10.
Eur Respir J ; 33(6): 1302-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19164343

ABSTRACT

Montelukast and desloratadine synergistically inhibit the allergen-induced early asthmatic response. Montelukast also suppresses the allergen-induced late asthmatic response, but there are no reports on the effect of desloratadine or the combination on the allergen-induced late asthmatic response. Atopic asthmatics (n = 10) completed a multicentric randomised double-blind crossover study comparing single-dose placebo, 5 mg desloratadine, 10 mg montelukast and the combination administered 2 h prior to allergen inhalation challenge. Methacholine challenges were performed 24 h before and after allergen challenge. Exhaled nitric oxide measurements and sputum inflammatory cell counts were also carried out. All active treatments significantly decreased the late asthmatic response area under the curve. Combination therapy provided the greatest inhibition compared to desloratadine and montelukast. Montelukast was nonsignificantly better than desloratadine but not as effective as the combination. There was a trend towards a decrease in airway responsiveness following montelukast and combination. Montelukast, but not desloratadine or the combination, decreased exhaled NO levels 24 h after allergen. The allergen-induced increase in sputum eosinophil numbers was significantly suppressed at 7 h with desloratadine and combination therapy, and at 24 h with montelukast and combination therapy. Single-dose co-administration of desloratadine and montelukast 2 h prior to allergen inhalation clinically abolished the late asthmatic response and eosinophil recruitment.


Subject(s)
Acetates/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Histamine H1 Antagonists, Non-Sedating/therapeutic use , Leukotriene Antagonists/therapeutic use , Loratadine/analogs & derivatives , Quinolines/therapeutic use , Acetates/administration & dosage , Acetates/immunology , Adult , Allergens/immunology , Analysis of Variance , Anti-Asthmatic Agents/administration & dosage , Anti-Asthmatic Agents/immunology , Asthma/immunology , Bronchial Provocation Tests , Cross-Over Studies , Cyclopropanes , Double-Blind Method , Drug Therapy, Combination , Eosinophils , Female , Humans , Leukotriene Antagonists/administration & dosage , Leukotriene Antagonists/immunology , Loratadine/administration & dosage , Loratadine/immunology , Loratadine/therapeutic use , Male , Methacholine Chloride , Middle Aged , Nitric Oxide/metabolism , Placebos , Quinolines/administration & dosage , Quinolines/immunology , Respiratory Function Tests , Sputum/cytology , Sulfides , Treatment Outcome
11.
Allergy ; 62(10): 1139-45, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17845582

ABSTRACT

BACKGROUND: Dendritic cells are key contributors to initiation and maintenance of T-cell immunity to inhaled allergen. The purpose of this study was to enumerate the changes in peripheral blood myeloid (mDCs) and plasmacytoid dendritic cells (pDCs), the DCs expressing chemokine receptor 6 (CCR6) and chemokine receptor 7 (CCR7), following diluent and allergen inhalation in asthmatic subjects. METHODS: Peripheral blood was obtained from 16 allergic asthmatic subjects before and at 0.5, 1, 2, 3, 4, 6, 24, and 48 h after inhaled diluent and allergen challenges. Dendritic cells were enumerated using flow cytometry. RESULTS: Allergen inhalation significantly reduced mDCs at 6 h (21.3 +/- 2.0 vs 15.0 +/- 1.8/microl blood; P < 0.05) and 24 h (21.5 +/- 3.4 vs 16.4 +/- 2.4/microl blood; P < 0.05) after challenge. Circulating pDCs were significantly lower than baseline up to 24 h after both allergen and diluent challenges. There was a significant efflux of CCR6(+) mDCs from peripheral blood at 6 h and CCR6(+) pDCs at 4 h after allergen challenge, when compared with diluent. There was no difference in the number of circulating CCR7(+) mDCs or pDCs after diluent or allergen challenges. CONCLUSIONS: Peripheral blood mDCs and CCR6(+) mDCs, but not pDCs, are reduced up to 24 h after allergen inhalation. Thus, allergen inhalation causes trafficking of immature CCR6(+) DCs from blood into the airway, while that of the trafficking of the mature CCR7(+) DCs from the airways into the regional lymph nodes probably occurs through the lymphatic system.


Subject(s)
Asthma/blood , Asthma/immunology , Dendritic Cells/immunology , Myeloid Cells/immunology , Adolescent , Adult , Allergens , Animals , Asthma/chemically induced , Bronchial Provocation Tests/adverse effects , Flow Cytometry , Humans , Leukocytes/drug effects , Leukocytes/metabolism , Lymphocyte Count , Middle Aged , Protein Transport , Receptors, CCR6/blood , Receptors, CCR7/blood
12.
Clin Exp Allergy ; 36(11): 1417-24, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17083352

ABSTRACT

BACKGROUND: The predominance of T-helper type 2 (Th2) lymphocytes is thought to underlie the pathogenesis of asthma. Allergen inhalation challenge in atopic asthmatic subjects is associated with decreased interferon-gamma (IFN-gamma) positive CD4+ and CD8+ lymphocytes in peripheral blood and induced sputum. OBJECTIVE: This study examined the effects of an inhaled corticosteroid on these previously described allergen-induced changes in circulating Th1 and Th2 lymphocytes. METHODS: Subjects were randomized to 7 days of placebo, 40 or 80 micro g ciclesonide in a crossover study. Airway responses and peripheral blood were measured before and after treatment, and 24 h after allergen challenge. RESULTS: Ciclesonide 40 and 80 micro g significantly attenuated the late response and sputum eosinophils at 8 h post-allergen (P<0.05). Circulating IFN-gamma positive CD4+ lymphocytes decreased after allergen challenge with placebo (P<0.05), and this was inhibited by 40 micro g ciclesonide treatment (P<0.05). There was no effect of allergen inhalation or ciclesonide on IL-4-positive CD4+ lymphocytes or IFN-gamma and IL-4-positive CD8(high) lymphocytes. The allergen-induced change of IFN-gamma/IL-4 ratio on CD4+ cells correlated with the allergen-induced change of peripheral blood eosinophils. CONCLUSIONS: The results of this study suggest that attenuation of allergen-induced airway responses by ciclesonide may be mediated through regulation of IFN-gamma-positive CD4+ cells.


Subject(s)
Asthma/drug therapy , CD4-Positive T-Lymphocytes/immunology , Glucocorticoids/administration & dosage , Hypersensitivity/drug therapy , Pregnenediones/administration & dosage , Administration, Inhalation , Adult , Allergens , Analysis of Variance , Asthma/immunology , Biomarkers/analysis , Bronchial Provocation Tests , CD8-Positive T-Lymphocytes/immunology , Cross-Over Studies , Double-Blind Method , Drug Administration Schedule , Eosinophils/immunology , Female , Flow Cytometry , Glucocorticoids/therapeutic use , Humans , Hypersensitivity/immunology , Interferon-gamma/analysis , Interleukin-4/analysis , Lymphocyte Count , Male , Methacholine Chloride , Pregnenediones/therapeutic use , Sputum/immunology
13.
Allergy ; 60(1): 56-9, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15575931

ABSTRACT

BACKGROUND: The allergen-induced early asthmatic response [provocation concentration (PC)20, the concentration causing a 20% forced expiratory volume in 1 s (FEV)1 fall] depends on the level of IgE sensitivity and the degree of nonallergic airway hyperresponsiveness (AHR) and can be predicted from histamine PC20 and allergen skin test endpoint. OBJECTIVES: We examined the relationships between allergen PC20, methacholine PC20, and allergen skin test endpoint and assessed the accuracy of both the histamine PC20-based prediction of allergen PC20 (using methacholine) and a new methacholine PC20-based prediction equation. METHODS: From 158 allergen challenges, the allergen PC20, the methacholine PC20, and the skin test endpoint were recorded and relationships between these three were sought. We compared the measured allergen PC20 to that predicted from the previous histamine PC20-based and the new methacholine-based formulae. RESULTS: In single regressions, allergen PC20 correlated with both methacholine PC20 (r=0.25, P=0.0015) and skin test endpoint (r=0.52, P <0.00005). The relationship was improved by multiple regression of log-allergen PC20vs. log-methacholine PC20 and log-endpoint (r=0.61, P <0.00005). The histamine-based formula predicted allergen PC20 to within 2 doubling concentrations in 80% and within 3 in 92%. The new methacholine-based formula to within 2 and 3 concentrations in 81% and 94%, respectively; only nine of 158 subjects were outside the 3 concentrations. CONCLUSIONS: We have confirmed the dependence of the allergen-induced early asthmatic response upon the level of allergic sensitivity and the degree of AHR, the latter as assessed by methacholine challenge. The allergen PC20 can be predicted to within 3 doubling concentrations in 94% of cases.


Subject(s)
Allergens/immunology , Asthma/immunology , Bronchi/immunology , Bronchial Hyperreactivity/immunology , Hypersensitivity/immunology , Skin Tests , Adult , Bronchial Hyperreactivity/diagnosis , Bronchial Hyperreactivity/physiopathology , Bronchial Provocation Tests , Bronchoconstrictor Agents , Female , Forced Expiratory Volume , Humans , Male , Methacholine Chloride , Models, Biological , Retrospective Studies
14.
Int J Oral Maxillofac Surg ; 31(3): 244-51, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12190128

ABSTRACT

Laser scanning techniques are used to plan the construction of prosthetic ears as dimensional measurements between anthropometric points can be accurately measured on a screen image. The aim of this study was to determine if these techniques could be used to assess the position of ears on the face. Computer-generated images were created from laser scans of 20 subjects. Frames of reference were constructed by locating a series of anthropometric points on the face from which three orthogonal planes were constructed. A central reference point was identified at the intersection of the three orthogonal planes. Dimensional measurements were made between anthropometric points on the ear and the reference planes. The differences between anthropometric points and the reference planes on the left and right sides of the face were small. It was possible to describe the location of points three-dimensionally with respect to a central reference point. The development of frames of reference and a central reference point would appear to offer many advantages in the assessment and description of ear position for patients requiring reconstruction with prostheses.


Subject(s)
Cephalometry/instrumentation , Ear, External/anatomy & histology , Lasers , Prostheses and Implants , Adolescent , Adult , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Models, Anatomic , Patient Care Planning , Rehabilitation , Reproducibility of Results
15.
Am J Respir Crit Care Med ; 164(8 Pt 1): 1495-500, 2001 Oct 15.
Article in English | MEDLINE | ID: mdl-11704602

ABSTRACT

Allergen-induced late airway responses are associated with increased numbers of airway eosinophils and basophils. The purpose of this study was to compare and contrast the effects of inhaled cysteinyl leukotrienes LTD(4) and LTE(4), which are released during allergen- induced airway responses, and allergen, on airway inflammatory cells. Fifteen subjects with atopic, mild asthma inhaled diluent, LTD(4), LTE(4), and allergen. Spirometry was performed for 7 h, and sputum inflammatory cells were measured before, 7 h, and 24 h after challenges. The maximum early percent fall in FEV(1) was 23.6 +/- 1.4%, 21.6 +/- 2.3%, 29.3 +/- 2.4%, and 4.0 +/- 1.1% after LTD(4), LTE(4), allergen, and diluent, respectively. Only inhaled LTE(4) and allergen significantly increased sputum eosinophils at 7 h and 24 h, and sputum basophils at 7 h. Six additional subjects underwent airway biopsies 4 h after inhalation. There were significantly more eosinophils in the lamina propria after inhalation of LTE(4) compared with LTD(4) and diluent (p < 0.05). These results suggest cysteinyl leukotrienes play a role in eosinophil migration into the airways in allergic asthma, and for the same degree of bronchoconstriction, inhaled LTE(4) causes more tissue and airway eosinophilia than LTD(4).


Subject(s)
Asthma/immunology , Leukotriene D4 , Leukotriene E4 , Administration, Inhalation , Adult , Asthma/pathology , Basophils/immunology , Cross-Over Studies , Double-Blind Method , Eosinophils/immunology , Female , Humans , Leukotriene D4/administration & dosage , Leukotriene E4/administration & dosage , Male , Mast Cells/immunology
16.
Biochemistry ; 40(46): 14037-46, 2001 Nov 20.
Article in English | MEDLINE | ID: mdl-11705396

ABSTRACT

Pediocin AcH is a 44-residue antimicrobial peptide with bactericidal potency against Gram-positive bacteria such as Listeria. It belongs to a family of bacteriocins that, when membrane-associated, is predicted to contain beta-sheet and alpha-helical regions. All bacteriocins in this family have a conserved N-terminal disulfide bond. An additional C-terminal disulfide bond in pediocin AcH is thought to confer enhanced potency and broader specificity range against sensitive bacteria. The C-terminal disulfide bond may also affect the conformation of the C-terminus. The secondary structures of pediocin AcH in aqueous solution and vesicles from susceptible cells, as well as the ability of trifluoroethanol (TFE) and detergent systems to induce secondary structures like those induced in vesicles, were studied by circular dichroism (CD) spectroscopy. Like related peptides, pediocin AcH was highly unordered in aqueous solution, 56%. However, it also contained 20% beta-strand and 15% beta-turn structures. Upon complete binding to vesicles, 32% alpha-helical structure formed, the unordered structure decreased to 32%, and the beta-strand and beta-turn structures remained largely unchanged. Thus, a betaalpha domain structure formed in vesicles. The helical structure likely forces the C-terminal tail to loop back on the helix so that the C24-C44 disulfide bond can form. Detergent micelles were superior to TFE in their ability to induce secondary structural fractions in pediocin AcH comparable to those observed in vesicles. This demonstrates the importance of a hydrocarbon-water interface to pediocin AcH structure induction and suggests that it is preferable to use detergent micelles as solvents in NMR studies of pediocin AcH structure.


Subject(s)
Bacteriocins/chemistry , Detergents/chemistry , Micelles , Phospholipids/chemistry , Polysorbates/chemistry , Amino Acid Sequence , Bacteriocins/isolation & purification , Bacteriocins/metabolism , Buffers , Circular Dichroism , Listeria/chemistry , Mass Spectrometry , Molecular Sequence Data , Pediocins , Pediococcus/chemistry , Phospholipids/metabolism , Protein Binding , Protein Conformation , Protein Structure, Secondary , Trifluoroethanol/chemistry
17.
Am J Respir Crit Care Med ; 164(4): 569-74, 2001 Aug 15.
Article in English | MEDLINE | ID: mdl-11520717

ABSTRACT

Comparisons of the potency of different inhaled corticosteroids, delivery devices, and treatment regimens in the management of asthma can only be made when outcome measurements display a dose-dependent effect. These outcomes have been difficult to identify. In this study, we compared in a randomized, double-blind, crossover design, the effects of 6 d treatment with placebo and three doses (50, 100, and 400 microg, twice daily) of mometasone furoate delivered by dry powder inhaler (MF-DPI) on responses after allergen inhalation challenge. Twelve mild asthmatic subjects with dual responses after allergen inhalation were studied. Outcome measurements included early and late asthmatic responses, the change in methacholine airway responsiveness 24 h after challenge, and sputum eosinophilia measured 7 and 24 h after challenge. All three doses of MF-DPI demonstrated similar attenuation of early responses and allergen-induced airway hyperresponsiveness relative to placebo (p < 0.05). The late maximal %fall in FEV(1) after placebo treatment was 23.5% and was significantly reduced in a dose-dependent manner to 12.3%, 11.0%, and 5.9% for the 50-, 100-, and 400-microg twice-daily treatments (p = 0.007). The allergen-induced increase in sputum eosinophilia (x10(4) cells/ml) 24 h after challenge during placebo treatment was 60.2 and was significantly reduced to 24.0, 15.3, and 6.2 for the 50-, 100-, and 400-microg twice-daily treatments. MF-DPI is effective at attenuating allergen-induced early and late responses, airway hyperresponsiveness, and sputum eosinophilia, and dose-response effects exist for the attenuation of the late response.


Subject(s)
Airway Resistance/drug effects , Anti-Inflammatory Agents/administration & dosage , Asthma/drug therapy , Asthma/physiopathology , Pregnadienediols/administration & dosage , Administration, Inhalation , Adolescent , Adult , Allergens/adverse effects , Anti-Inflammatory Agents/immunology , Anti-Inflammatory Agents/pharmacology , Asthma/immunology , Bronchoconstrictor Agents/adverse effects , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Eosinophils/pathology , Female , Forced Expiratory Volume/drug effects , Humans , Inflammation , Male , Methacholine Chloride/adverse effects , Middle Aged , Mometasone Furoate , Pregnadienediols/immunology , Pregnadienediols/pharmacology , Severity of Illness Index , Sputum/cytology , Time Factors , Treatment Outcome
18.
Eur Respir J ; 17(4): 581-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11401049

ABSTRACT

Dry air exercise challenges are frequently used to screen medications that have potential utility in the management of exercise-induced bronchoconstriction (EIB). The purpose of this study was to determine the reproducibility of three outcome measurements made using such challenges, and sample size requirements for drug evaluation studies based on these outcomes. Forty adult subjects with asthma, who tested positively on a screening exercise challenge, were subjected to two further identical challenges, separated by 1 to >35 days. Outcome measurements included the maximum per cent fall in forced expiratory volume in one second (FEV1), after exercise (% fallmax), and the area under the per cent fall in FEV1/time curve for 30 min (AUC30) and 60 min (AUC60) after exercise. The reproducibility of these outcomes, as assessed by intraclass correlation coefficients was 0.72, 0.53 and 0.35 for % fallmax, AUC30 and AUC60 measurements, respectively. The sample size requirements to demonstrate an attenuation of EIB equivalent to a 50% reduction in % fallmax was 9, 14 and 19 subjects for the % fallmax, AUC30 and AUC60 responses, respectively (90% power). It is concluded that the maximum percentage fall in forced expiratory volume in one second has greater reproducibility and results in greater power in clinical trials than area under the curve measurements. Sample size calculation curves are provided which may be used in study design and interpretation of published studies.


Subject(s)
Asthma, Exercise-Induced/physiopathology , Bronchoconstriction/physiology , Adult , Drug Evaluation , Forced Expiratory Volume , Humans , Reproducibility of Results , Sample Size
19.
Br Dent J ; 190(6): 296-300, 2001 Mar 24.
Article in English | MEDLINE | ID: mdl-11325155

ABSTRACT

Different methods are recommended for the surgical reconstruction of the resected mandible. The advantages for implant stabilised prostheses in restoring the occlusion are recognised but few papers provide adequate data to identify the successful outcome of treatment. The literature is reviewed and the advantages of imaging together with the use of digitised data is highlighted by a case requiring rehabilitation with enhanced planning methods.


Subject(s)
Computer Simulation , Dental Prosthesis, Implant-Supported , Mandible/surgery , Oral Surgical Procedures, Preprosthetic/methods , Tomography, X-Ray Computed/methods , Bone Transplantation/methods , Dental Implantation, Endosseous , Female , Humans , Imaging, Three-Dimensional , Jaw Cysts/rehabilitation , Jaw Cysts/surgery , Mandible/diagnostic imaging , Mandibular Diseases/rehabilitation , Mandibular Diseases/surgery , Middle Aged , Models, Anatomic , Models, Dental , Patient Care Planning , Treatment Outcome
20.
Am J Respir Crit Care Med ; 162(6): 2139-44, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11112128

ABSTRACT

Allergen inhalation by dual responder subjects with atopic asthma is associated with an increase in circulating eosinophil/basophil colony-forming units (Eo/B CFU) and granulocyte-macrophage colony- stimulating factor (GM-CSF) immunolocalization in Eo/B colony cells grown in vitro. The current study examined the effect of the inhaled corticosteroid, budesonide, on the number of allergen- induced circulating eosinophils and Eo/B CFU, and immunolocalization of GM-CSF and interleukin-5 (IL-5) in Eo/B colony cells grown in vitro. Sixteen subjects with mild atopic asthma were treated for either 7 or 8 d with 200 microg inhaled budesonide or placebo twice a day. Peripheral blood was collected before and 24 h after allergen inhalation challenge and nonadherent mononuclear cells (NAMC) were grown in methylcellulose culture. Eo/B CFU were enumerated after 14 d in culture, and prepared on slides for immunocytochemistry. Budesonide attenuated the allergen-induced increase in circulating eosinophils (4.0 +/- 0.4 x 10(5)/ml versus 6.5 +/- 0.7 x 10(5)/ml, p = 0.0001), circulating Eo/B CFU (12.4 +/- 2.3/10(6) NAMC versus 18.8 +/- 4.6/10(6) NAMC, p = 0.05), and immunolocalization of GM-CSF in Eo/B colony cells (11.8 +/- 1.9% positive versus 18.0 +/- 2.2%, p = 0.01) but not immunolocalization of IL-5 (7.9 +/- 1.4% versus 4.5 +/- 0.6%, p > 0.05). Inhaled budesonide attenuated the number of allergen-induced circulating eosinophils and their progenitors grown in the presence of GM-CSF, which may partially be a result of regulating eosinophil progenitor expression of the autocrine growth factor GM-CSF.


Subject(s)
Allergens , Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Budesonide/administration & dosage , Cytokines/drug effects , Eosinophils/drug effects , Stem Cells/drug effects , Administration, Inhalation , Analysis of Variance , Asthma/blood , Asthma/diagnosis , Asthma/immunology , Bronchial Provocation Tests/methods , Bronchial Provocation Tests/statistics & numerical data , Colony-Forming Units Assay/methods , Colony-Forming Units Assay/statistics & numerical data , Cross-Over Studies , Cytokines/blood , Double-Blind Method , Eosinophils/immunology , Humans , Stem Cells/immunology , Time Factors
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