23 results on '"Hostettler K"'
Search Results
2. Azithromycin alters spatial and temporal dynamics of airway microbiota in idiopathic pulmonary fibrosis.
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Gijs PJ, Daccord C, Bernasconi E, Brutsche M, Clarenbach CF, Hostettler K, Guler SA, Mercier L, Ubags N, Funke-Chambour M, and von Garnier C
- Abstract
Background: High bacterial burden in the lung microbiota predicts progression of idiopathic pulmonary fibrosis (IPF). Azithromycin (AZT) is a macrolide antibiotic known to alter the lung microbiota in several chronic pulmonary diseases, and observational studies have shown a positive effect of AZT on mortality and hospitalisation rate in IPF. However, the effect of AZT on the lung microbiota in IPF remains unknown., Methods: We sought to determine the impact of a 3-month course of AZT on the lung microbiota in IPF. We assessed sputum and oropharyngeal swab specimens from 24 adults with IPF included in a randomised controlled crossover trial of oral AZT 500 mg 3 times per week. 16S rRNA gene amplicon sequencing and quantitative PCR (qPCR) were performed to assess bacterial communities. Antibiotic resistance genes (ARGs) were assessed using real-time qPCR., Results: AZT significantly decreased community diversity with a stronger and more persistent effect in the lower airways (sputum). AZT treatment altered the temporal kinetics of the upper (oropharyngeal swab) and lower airway microbiota, increasing community similarity between the two sites for 1 month after macrolide cessation. Patients with an increase in ARG carriage had lower bacterial density and enrichment of the genus Streptococcus . In contrast, patients with more stable ARG carriage had higher bacterial density and enrichment in Prevotella ., Conclusions: AZT caused sustained changes in the diversity and composition of the upper and lower airway microbiota in IPF, with effects on the temporal and spatial dynamics between the two sites., Competing Interests: Conflict of interest: C.F. Clarenbach reports consulting fees from GSK, Novartis, Vifo, Boehringer, AstraZeneca, Sanofi and Daiichi Sankyo, outside the submitted work; payment or honoraria from GSK, Novartis, Vifor, Boehringer, AstraZeneca and Sanofi, outside the submitted work; support for attending meetings and/or travel from Boehringer and AstraZeneca, outside the submitted work. S.A. Guler reports payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from MSD, Boehringer Ingelheim and Roche, outside the submitted work. M. Funke-Chambour reports support for the present manuscript from the Research Fund of the Swiss Lung Association, Bern; grants or contracts from Boehringer Ingelheim, Roche and CSL Behring, outside the submitted work; consulting fees from Boehringer Ingelheim and Daiichi Sankyo, outside the submitted work; payment or honoraria from MSD and Novartis, outside the submitted work. C. von Garnier reports grants or contracts from Ligue Pulmonaire Vaudoise, Fondation Juchum and Fondation Placide Nicod, outside the submitted work. The remaining authors have nothing to disclose., (Copyright ©The authors 2023.)
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- 2023
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3. Prodrugs of E-selectin Antagonists with Enhanced Pharmacokinetic Properties.
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Dätwyler P, Jiang X, Wagner B, Varga N, Mühlethaler T, Hostettler K, Rabbani S, Schwardt O, and Ernst B
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- Administration, Oral, Animals, Biological Availability, Caco-2 Cells, Dose-Response Relationship, Drug, E-Selectin metabolism, Esters administration & dosage, Esters chemistry, Female, Humans, Male, Mice, Mice, Inbred BALB C, Microsomes, Liver chemistry, Microsomes, Liver metabolism, Molecular Structure, Prodrugs administration & dosage, Prodrugs chemistry, Rats, Structure-Activity Relationship, E-Selectin antagonists & inhibitors, Esters pharmacology, Prodrugs pharmacology
- Abstract
Because of their large polar surface area, carbohydrates often exhibit insufficient pharmacokinetic properties. Specifically, the carboxylic acid function of the tetrasaccharide sialyl Lewis
x , a pharmacophore crucial for the formation of a salt bridge with selectins, prevents oral availability. A common approach is the transfer of carboxylic acid into ester prodrugs. Once the prodrug is either actively or passively absorbed, the active principle is released by hydrolysis. In the present study, ester prodrugs of selectin antagonists with aliphatic promoieties were synthesized and their potential for oral availability was investigated in vitro and in vivo. The addition of lipophilic ester moieties to overcome insufficient lipophilicity improved passive permeation into enterocytes, however at the same time supported efflux back to the small intestines as well as oxidation into non-hydrolysable metabolites. In summary, our examples demonstrate that different modifications of carbohydrates can result in opposing effects and have to be studied in their entirety., (© 2021 Wiley-VCH GmbH.)- Published
- 2022
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4. Azithromycin for the Treatment of Chronic Cough in Idiopathic Pulmonary Fibrosis: A Randomized Controlled Crossover Trial.
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Guler SA, Clarenbach C, Brutsche M, Hostettler K, Brill AK, Schertel A, Geiser TK, and Funke-Chambour M
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- Aged, Cough drug therapy, Cough etiology, Cross-Over Studies, Double-Blind Method, Female, Humans, Male, Quality of Life, Treatment Outcome, Azithromycin, Idiopathic Pulmonary Fibrosis complications, Idiopathic Pulmonary Fibrosis drug therapy
- Abstract
Rationale: Patients with idiopathic pulmonary fibrosis (IPF) frequently suffer from chronic cough that is difficult to treat, which substantially affects their quality of life. Azithromycin has been demonstrated to relieve chronic cough in some populations; however, this has not been investigated in patients with IPF. Objectives: To determine the safety and efficacy of azithromycin for the treatment of chronic cough in patients with IPF. Methods: In a double-blind randomized controlled crossover trial, patients with IPF underwent two 12-week intervention periods (azithromycin 500 mg three times per week or placebo three times per week). The primary outcome was the change in cough-related quality of life as measured by the Leicester Cough Questionnaire (LCQ). Secondary outcomes included cough severity as measured by the Visual Analog Scale (VAS), health-related quality of life as assessed by the St. George's Respiratory Questionnaire, and objective cough frequency as measured by audiovisual readings from 24-hour respiratory polygraphy. Results: Twenty-five patients were randomized (23 men, 2 women); 20 patients completed the study. The mean (standard deviation [SD]) age was 67 (8) years, the mean (SD) forced vital capacity was 65 (16) percent predicted, and the diffusing capacity of the lung for carbon monoxide was 43 (16) percent predicted. The mean (SD) baseline LCQ scores were 11.7 (3.7) and 11.3 (3.3) for the azithromycin period and the placebo period, respectively, and the corresponding mean (SD) cough VAS scores were 5.6 (2.3) and 5.8 (2.1). There was no significant change in the LCQ score or the VAS score with azithromycin or with placebo. Similarly, there was no significant difference between the azithromycin period and the placebo period for change in polygraphy-measured cough frequency. Gastrointestinal adverse effects were more frequent with azithromycin than with placebo (diarrhea, 43% vs. 5%; P = 0.03). Conclusions: This randomized controlled trial does not support the use of low-dose azithromycin for chronic cough in patients with IPF.Clinical trial registered with www.clinicaltrials.gov (NCT02173145).
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- 2021
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5. IPF-Fibroblast Erk1/2 Activity Is Independent from microRNA Cluster 17-92 but Can Be Inhibited by Treprostinil through DUSP1.
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Blumer S, Fang L, Chen WC, Khan P, Hostettler K, Tamm M, Roth M, and Lambers C
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- Cell Proliferation drug effects, Cell Proliferation genetics, Cells, Cultured, Epoprostenol pharmacology, Female, Fibroblasts drug effects, Fibroblasts pathology, Gene Expression Regulation drug effects, Humans, Idiopathic Pulmonary Fibrosis enzymology, Male, Middle Aged, Transforming Growth Factor beta1 metabolism, Dual Specificity Phosphatase 1 metabolism, Epoprostenol analogs & derivatives, Extracellular Signal-Regulated MAP Kinases metabolism, Fibroblasts metabolism, Idiopathic Pulmonary Fibrosis genetics, Idiopathic Pulmonary Fibrosis pathology
- Abstract
Idiopathic pulmonary fibrosis (IPF) is a progressive terminal lung disease, and therapies aim to block fibrosis. Fibroblast proliferation is controlled by C/EBP-β, microRNA cluster 17-92 (miR17-92), and Erk1/2 mitogen-activated protein kinase. This study assessed the role of miR17-92 in IPF-fibroblast proliferation and its modification by treprostinil. Fibroblasts were isolated from eight IPF patients, five interstitial lung fibrosis patients, and seven control lungs. Fibroblasts were stimulated with TGF-β1 over 24 h. The miR17-92 expression was analyzed by RT-qPCR, and protein expression by Western blotting. TGF-β1 upregulated C/EBP-β in all fibroblasts, which was reduced by treprostinil in control-fibroblasts, but not in IPF-fibroblasts. Compared to controls, the guide strands miR-19a-3p, miR-19b-3p, miR-20a-5p, and miR-92a-3p, as well as the passenger strands miR-17-3p, miR-18-3p, miR-19a-1-5p, and miR-92a-5p were significantly increased in IPF-fibroblasts. In controls, TGF-β1 and treprostinil significantly reduced specific miR17-92 members. IPF-fibroblast proliferation was inhibited by treprostinil through increased expression of the Erk1/2 inhibitor DUSP1. These data suggest that proliferation control via miR17-92 and C/EBP-β is disrupted in IPF-fibroblasts. Therefore, the inhibition of early stages of signaling cascades or specific mitogen receptors might be less effective. However, the increased proliferation is sensitive to Erk1/2 inhibition by treprostinil-induced DUSP1.
- Published
- 2021
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6. Ninety-day outcome of patients with severe COVID-19 treated with tocilizumab - a single centre cohort study.
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Sava M, Sommer G, Daikeler T, Woischnig AK, Martinez AE, Leuzinger K, Hirsch HH, Erlanger T, Wiencierz A, Bassetti S, Tamm M, Tschudin-Sutter S, Stoeckle M, Pargger H, Siegemund M, Boss R, Zimmer G, Vu DL, Kaiser L, Dell-Kuster S, Weisser M, Battegay M, Hostettler K, and Khanna N
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- Antibodies, Monoclonal, Humanized, Cohort Studies, Humans, Prospective Studies, SARS-CoV-2, COVID-19 Drug Treatment
- Abstract
Objectives: Patients with severe COVID-19 may be at risk of longer term sequelae. Long-term clinical, immunological, pulmonary and radiological outcomes of patients treated with anti-inflammatory drugs are lacking., Methods: In this single-centre prospective cohort study, we assessed 90-day clinical, immunological, pulmonary and radiological outcomes of hospitalised patients with severe COVID-19 treated with tocilizumab from March 2020 to May 2020. Criteria for tocilizumab administration were oxygen saturation <93%, respiratory rate >30/min, C-reactive protein levels >75 mg/l, extensive area of ground-glass opacities or progression on computed tomography (CT). Descriptive analyses were performed using StataIC 16., Results: Between March 2020 and May 2020, 50 (27%) of 186 hospitalised patients had severe COVID-19 and were treated with tocilizumab. Of these, 52% were hospitalised on the intensive care unit (ICU) and 12% died. Eleven (22%) patients developed at least one microbiologically confirmed super-infection, of which 91% occurred on ICU. Median duration of hospitalisation was 15 days (interquartile range [IQR] 10–24) with 24 days (IQR 14–32) in ICU patients and 10 days (IQR 7–15) in non-ICU patients. At day 90, 41 of 44 survivors (93%) were outpatients. No long-term adverse events or late-onset infections were identified after acute hospital care. High SARS-CoV-2 antibody titres were found in all but one patient, who was pretreated with rituximab. Pulmonary function tests showed no obstructive patterns, but restrictive patterns in two (5.7%) and impaired diffusion capacities for carbon monoxide in 11 (31%) of 35 patients, which predominated in prior ICU patients. Twenty-one of 35 (60%) CT-scans at day 90 showed residual abnormalities, with similar distributions between prior ICU and non-ICU patients., Conclusions: In this cohort of severe COVID-19 patients, no tocilizumab-related long-term adverse events or late-onset infections were identified. Although chest CT abnormalities were highly prevalent at day 90, the majority of patients showed normal lung function., Trial Registration: ClinicalTrials.gov NCT04351503.
- Published
- 2021
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7. Centralized expert HRCT Reading in suspected idiopathic pulmonary fibrosis: Experience from an Eurasian teleradiology program.
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Weikert T, Sommer G, Tamm M, Haegler P, Cyriac J, Sauter AW, Hostettler K, and Bremerich J
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- Asia, Europe, Female, Humans, Image Interpretation, Computer-Assisted methods, Lung diagnostic imaging, Male, Middle Aged, Idiopathic Pulmonary Fibrosis diagnostic imaging, Teleradiology methods, Tomography, X-Ray Computed methods
- Abstract
Purpose: To share experience from a large, ongoing expert reading teleradiology program in Europe and Asia aiming at supporting referring centers to interpret high-resolution computed tomography (HRCT) with respect to presence of Usual Interstitial Pneumonia (UIP)-pattern in patients with suspected Idiopathic Pulmonary Fibrosis (IPF)., Method: We analyzed data from 01/2014 to 05/2019, including HRCTs from 239 medical centers in 12 European and Asian countries that were transmitted to our Picture Archiving and Communication System (PACS) via a secured internet connection. Structured reports were generated in consensus by a radiologist with over 20 years of experience in thoracic imaging and a pulmonologist with specific expertise in interstitial lung disease according to current guidelines on IPF. Reports were sent to referring physicians. We evaluated patient characteristics, technical issues, report turnaround times and frequency of diagnoses. We also conducted a survey to collect feedback from referring physicians., Results: HRCT image data from 703 patients were transmitted (53.5% male). Mean age was 63.7 years (SD:17). In 35.1% of all cases diagnosis was "UIP"/"Typical UIP". The mean report turnaround time was 1.7 days (SD:2.9). Data transmission errors occurred in 7.1%. Overall satisfaction rate among referring physicians was high (8.4 out of 10; SD:3.2)., Conclusions: This Eurasian teleradiology program demonstrates the feasibility of cross-border teleradiology for the provision of state-of-the-art reporting despite heterogeneity of referring medical centers and challenges like data transmission errors and language barriers. We also point out important factors for success like the usage of structured reporting templates., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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8. Bosentan for patients with steroid-resistant pulmonary sarcoidosis: a randomised controlled trial.
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Hostettler K, Baty F, Kleiner R, Junker L, Tamm M, and Brutsche M
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- Adult, Double-Blind Method, Female, Forced Expiratory Volume drug effects, Humans, Male, Middle Aged, Oxygen analysis, Prospective Studies, Tomography, X-Ray Computed statistics & numerical data, Treatment Outcome, Bosentan therapeutic use, Endothelin Receptor Antagonists therapeutic use, Respiratory Function Tests statistics & numerical data, Sarcoidosis, Pulmonary drug therapy
- Abstract
Background: Sarcoidosis is a disorder of unknown aetiology. Most patients have steroid-responsive disease, but side effects and steroid resistance may necessitate alternative treatments. Endothelin has in-vitro fibrogenic activity and the endothelin system is activated in sarcoidosis., Objectives: We studied the efficacy and safety of the endothelin receptor antagonist bosentan in sarcoidosis patients., Methods: In a prospective 12-month, double-blind, 1:1-randomised, placebo-controlled phase II trial, we assessed the effect of bosentan in patients with steroid-resistant sarcoidosis and with impaired exercise capacity and/or resting lung function. Primary endpoints were safety and overall response rate of total lung capacity, diffusion capacity, peak oxygen uptake, 6-minute walking distance and chest computed tomography score. Secondary endpoints included adverse events and quality of life., Main Results: Twenty patients were randomised. Three patients discontinued the study medication prematurely. No serious drug-related adverse events occurred. At 12 months no statistically significant differences were observed in the primary endpoints including total lung capacity, diffusion capacity, 6-minute walking distance, peak oxygen uptake, and computed tomography-score. Sixty-three percent of the patients treated with bosentan showed an increase of 10% in at least one of the primary endpoints, compared with 67% in the placebo group (p = 1)., Conclusions: There is no evidence to support efficacy of bosentan as an antifibrotic treatment for patients with steroid-resistant pulmonary sarcoidosis. Bosentan was well tolerated and no drug-related adverse effects were observed within the study population., Trial Registration: ISRCTN registry, ISRCTN73579020.
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- 2018
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9. "Paintings Fade Like Flowers": Pigment Analysis and Digital Reconstruction of a Faded Pink Lake Pigment in Vincent van Gogh's Undergrowth with Two Figures.
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Fieberg JE, Knutås P, Hostettler K, and Smith GD
- Abstract
Color fading in Vincent van Gogh's Undergrowth with Two Figures was studied chemically to facilitate the creation of a digital reconstruction of fugitive colors . The painting contains a field of white, green, orange, and yellow flowers under a canopy of poplar trees with two central figures-a man and a woman, arms entwined. From Van Gogh's letters, however, it is known that he painted the picture with some pink flowers, which appear to have altered, presumably to white. Raman spectroscopy was applied to microsamples of paint to identify the faded pigment as geranium lake, which in this painting consists of the dye, eosin (2',4',5',7'-tetrabromofluorescein). For the first time, lead(II) sulfate has been specifically identified as the likely inorganic substrate for a geranium lake used by Van Gogh in the last months of his life. Microfocus X-ray fluorescence (MXRF) spectroscopy was subsequently used in situ to analyze the white flowers to identify bromine as a proxy for eosin, thus indicating an original pink coloration. Of the 387 white flowers analyzed, 37.7% contained measurable bromine and were, therefore, originally pink. Several cross-sections from these formerly pink areas were assessed using a combination of visual inspection and microcolorimetry to create a colored mask in Adobe Photoshop to digitally reconstruct a suggestion of the original appearance of the painting with regard to the faded flowers. Additionally, microfadeometry was undertaken for the first time on a painting cross-section sample to understand the actual fading kinetics of the underlying bright pink geranium lake used by Van Gogh. A combination of Raman microspectroscopy, MXRF, and scanning electron microscopy energy dispersive spectroscopy (SEM-EDS) were utilized in situ and on paint microsamples to identify the complete palette used to create Undergrowth with Two Figures.
- Published
- 2017
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10. Human Bronchial Epithelial Cells Induce CD141/CD123/DC-SIGN/ FLT3 Monocytes That Promote Allogeneic Th17 Differentiation.
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Gazdhar A, Blank F, Cesson V, Lovis A, Aubert JD, Lazor R, Spertini F, Wilson A, Hostettler K, Nicod LP, and Obregon C
- Abstract
Little is known about monocyte differentiation in the lung mucosal environment and about how the epithelium shapes monocyte function. We studied the role of the soluble component of bronchial epithelial cells (BECs) obtained under basal culture conditions in innate and adaptive monocyte responses. Monocytes cultured in bronchial epithelial cell-conditioned media (BEC-CM) specifically upregulate CD141, CD123, and DC-SIGN surface levels and FLT3 expression, as well as the release of IL-1β, IL-6, and IL-10. BEC-conditioned monocytes stimulate naive T cells to produce IL-17 through IL-1β mechanism and also trigger IL-10 production by memory T cells. Furthermore, monocytes cultured in an inflammatory environment induced by the cytokines IL-6, IL-8, IL-1β, IL-15, TNF-α, and GM-CSF also upregulate CD123 and DC-SIGN expression. However, only inflammatory cytokines in the epithelial environment boost the expression of CD141. Interestingly, we identified a CD141/CD123/DC-SIGN triple positive population in the bronchoalveolar lavage fluid (BALF) from patients with different inflammatory conditions, demonstrating that this monocyte population exists in vivo . The frequency of this monocyte population was significantly increased in patients with sarcoidosis, suggesting a role in inflammatory mechanisms. Overall, these data highlight the specific role that the epithelium plays in shaping monocyte responses. Therefore, the unraveling of these mechanisms contributes to the understanding of the function that the epithelium may play in vivo .
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- 2017
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11. Hepatocyte growth factor secreted by bone marrow stem cell reduce ER stress and improves repair in alveolar epithelial II cells.
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Nita I, Hostettler K, Tamo L, Medová M, Bombaci G, Zhong J, Allam R, Zimmer Y, Roth M, Geiser T, and Gazdhar A
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- Alveolar Epithelial Cells drug effects, Cell Line, Tumor, Cells, Cultured, Culture Media, Conditioned pharmacology, Endoplasmic Reticulum Chaperone BiP, Hepatocyte Growth Factor metabolism, Humans, Thapsigargin toxicity, Tunicamycin toxicity, Alveolar Epithelial Cells metabolism, Bone Marrow Cells metabolism, Endoplasmic Reticulum Stress, Hepatocyte Growth Factor pharmacology
- Abstract
Idiopathic Pulmonary Fibrosis (IPF) is a progressive, irreversible lung disease with complex pathophysiology. Evidence of endoplasmic reticulum (ER) stress has been reported in alveolar epithelial cells (AEC) in IPF patients. Secreted mediators from bone marrow stem cells (BMSC-cm) have regenerative properties. In this study we investigate the beneficial effects of BMSC-cm on ER stress response in primary AEC and ER stressed A549 cells. We hypothesize that BMSC-cm reduces ER stress. Primary AEC isolated from IPF patients were treated with BMSC-cm. To induce ER stress A549 cells were incubated with Tunicamycin or Thapsigargin and treated with BMSC-cm, or control media. Primary IPF-AEC had high Grp78 and CHOP gene expression, which was lowered after BMSC-cm treatment. Similar results were observed in ER stressed A549 cells. Alveolar epithelial repair increased in presence of BMSC-cm in ER stressed A549 cells. Hepatocyte growth factor (HGF) was detected in biologically relevant levels in BMSC-cm. Neutralization of HGF in BMSC-cm attenuated the beneficial effects of BMSC-cm including synthesis of surfactant protein C (SP-C) in primary AEC, indicating a crucial role of HGF in ER homeostasis and alveolar epithelial repair. Our data suggest that BMSC-cm may be a potential therapeutic option for treating pulmonary fibrosis., Competing Interests: The authors declare no competing financial interests.
- Published
- 2017
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12. Idiopathic Pulmonary Fibrosis in Switzerland: Diagnosis and Treatment.
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Funke-Chambour M, Azzola A, Adler D, Barazzone-Argiroffo C, Benden C, Boehler A, Bridevaux PO, Brutsche M, Clarenbach CF, Hostettler K, Kleiner-Finger R, Nicod LP, Soccal PM, Tamm M, Geiser T, and Lazor R
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- Humans, Hypertension, Pulmonary etiology, Idiopathic Pulmonary Fibrosis complications, Lung Transplantation, Idiopathic Pulmonary Fibrosis diagnosis, Idiopathic Pulmonary Fibrosis therapy
- Abstract
Idiopathic pulmonary fibrosis (IPF) is a severe progressive and irreversible lung disease. Novel antifibrotic drugs that slow disease progression are now available. However, many issues regarding patient management remain unanswered, such as the choice between available drugs, their use in particular subgroups and clinical situations, time of treatment onset, termination, combination or switch, or nonpharmacologic management. To guide Swiss respiratory physicians in this evolving field still characterized by numerous areas of uncertainty, the Swiss Working Group for interstitial and rare lung diseases of the Swiss Respiratory Society provides a position paper on the diagnosis and treatment of IPF., (© 2017 S. Karger AG, Basel.)
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- 2017
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13. [Idiopathic pulmonary fibrosis--Pathogenesis and therapeutic concepts].
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Hostettler K
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- Evidence-Based Medicine, Genetic Predisposition to Disease genetics, Humans, Lung drug effects, Lung Diseases, Interstitial genetics, Treatment Outcome, Anti-Inflammatory Agents therapeutic use, Lung immunology, Lung Diseases, Interstitial drug therapy, Lung Diseases, Interstitial immunology, Lung Injury immunology, Pneumonia, Viral immunology
- Abstract
Idiopathic pulmonary fibrosis (IPF) is the most common form of idiopathic interstitial pneumonias (IIP). It is characterized by progressive destruction of the normal lung architecture, finally leading to death. The pathogenesis of IPF is not completely understood but a complex interplay between environmental factors, such as smoking or viral infections, and genetic predisposition seems to be an important precondition. Repetitive micro-injuries to alveolar epithelial cells and dysregulated wound repair with impaired re-epithelialization are regarded as the initial process of IPF. This alveolar damage is followed by an uncontrolled proliferation and extracellular matrix deposition of fibroblasts, ultimately leading to distortion of the lung parenchyma. According to this "non-inflammatory" pathogenic hypothesis, therapeutic approaches currently focus on anti-fibrotic compounds, which prevent or inhibit fibroblast proliferation and extracellular matrix deposition, or antagonize the effect of pro-fibrotic growth factors.
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- 2016
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14. HGF Expressing Stem Cells in Usual Interstitial Pneumonia Originate from the Bone Marrow and Are Antifibrotic.
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Gazdhar A, Susuri N, Hostettler K, Gugger M, Knudsen L, Roth M, Ochs M, and Geiser T
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- A549 Cells, Animals, Bone Marrow physiology, Bone Marrow Cells cytology, Cell Differentiation physiology, Cell Separation, Cells, Cultured, Humans, Idiopathic Pulmonary Fibrosis pathology, Male, Rats, Rats, Inbred F344, Stem Cells metabolism, Stem Cells pathology, Bone Marrow Cells physiology, Hepatocyte Growth Factor metabolism, Idiopathic Pulmonary Fibrosis prevention & control, Pulmonary Alveoli cytology, Stem Cell Niche, Stem Cells cytology, Stem Cells physiology
- Abstract
Background: Pulmonary fibrosis may result from abnormal alveolar wound repair after injury. Hepatocyte growth factor (HGF) improves alveolar epithelial wound repair in the lung. Stem cells were shown to play a major role in lung injury, repair and fibrosis. We studied the presence, origin and antifibrotic properties of HGF-expressing stem cells in usual interstitial pneumonia., Methods: Immunohistochemistry was performed in lung tissue sections and primary alveolar epithelial cells obtained from patients with usual interstitial pneumonia (UIP, n = 7). Bone marrow derived stromal cells (BMSC) from adult male rats were transfected with HGF, instilled intratracheally into bleomycin injured rat lungs and analyzed 7 and 14 days later., Results: In UIP, HGF was expressed in specific cells mainly located in fibrotic areas close to the hyperplastic alveolar epithelium. HGF-positive cells showed strong co-staining for the mesenchymal stem cell markers CD44, CD29, CD105 and CD90, indicating stem cell origin. HGF-positive cells also co-stained for CXCR4 (HGF+/CXCR4+) indicating that they originate from the bone marrow. The stem cell characteristics were confirmed in HGF secreting cells isolated from UIP lung biopsies. In vivo experiments showed that HGF-expressing BMSC attenuated bleomycin induced pulmonary fibrosis in the rat, indicating a beneficial role of bone marrow derived, HGF secreting stem cells in lung fibrosis., Conclusions: HGF-positive stem cells are present in human fibrotic lung tissue (UIP) and originate from the bone marrow. Since HGF-transfected BMSC reduce bleomycin induced lung fibrosis in the bleomycin lung injury and fibrosis model, we assume that HGF-expressing, bone-marrow derived stem cells in UIP have antifibrotic properties.
- Published
- 2013
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15. Lung histology predicts outcome of bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation.
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Holbro A, Lehmann T, Girsberger S, Stern M, Gambazzi F, Lardinois D, Heim D, Passweg JR, Tichelli A, Bubendorf L, Savic S, Hostettler K, Grendelmeier P, Halter JP, and Tamm M
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- Adolescent, Adult, Biomarkers analysis, Biopsy, Bronchiolitis Obliterans drug therapy, Bronchiolitis Obliterans immunology, Bronchiolitis Obliterans mortality, Child, Female, Humans, Immunosuppressive Agents therapeutic use, Lung drug effects, Lung immunology, Lymphocytes drug effects, Lymphocytes immunology, Male, Middle Aged, Respiratory Function Tests, Retrospective Studies, Severity of Illness Index, Survival Analysis, Transplantation, Homologous, Treatment Outcome, Bronchiolitis Obliterans diagnosis, Hematopoietic Stem Cell Transplantation, Lung pathology, Lymphocytes pathology
- Abstract
Bronchiolitis obliterans (BO) is a severe complication after allogeneic hematopoietic stem cell transplantation with an unfavorable prognosis. Lung biopsy remains the gold standard for diagnosis. In this retrospective single-center study, we describe 33 patients who underwent biopsy for suspected BO. Ten patients had constrictive BO (CBO); 9 had lymphocytic bronchiolitis (LB), characterized by lymphocytic infiltration of the bronchioles. Six additional patients (4, CBO; 2, LB) had concomitant infection; 8 had other pathological diagnoses. Seven patients with CBO and 3 with LB met the National Institutes of Health consensus BO syndrome definition criteria. An additional 7 patients with histologically confirmed CBO did not meet the consensus definition, 4 of them because of concomitant airway infection. At diagnosis, there were no significant differences between the CBO and LB groups in clinical presentation; pulmonary function tests (median forced expiratory volume in one second [FEV1] at baseline, 90.4% and 99% predicted, at time of video-assisted thoracoscopic surgery, 55.1% and 60.8% for CBO and LB groups, respectively); and chest scans. Treatment was similar in both groups but outcome was different depending on histological findings. FEV1 significantly improved in LB patients compared with CBO patients. Survivals at 1 and 3 years were 77% ± 12% and 60% ± 14% for patients with CBO and 91% ± 9% for patients with LB (P = .028). Lung biopsy in patients with suspected BO enables better characterization of the pattern of BO syndrome. In contrast to CBO, LB is associated with a good long-term prognosis., (Copyright © 2013 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)
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- 2013
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16. Steroids and β2-agonists regulate hyaluronan metabolism in asthmatic airway smooth muscle cells.
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Papakonstantinou E, Klagas I, Karakiulakis G, Hostettler K, S'ng CT, Kotoula V, Savic S, Tamm M, and Roth M
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- Asthma pathology, Budesonide pharmacology, Case-Control Studies, Cell Adhesion Molecules genetics, Cell Adhesion Molecules metabolism, Cells, Cultured, Ethanolamines pharmacology, Extracellular Matrix metabolism, Formoterol Fumarate, GPI-Linked Proteins genetics, GPI-Linked Proteins metabolism, Gene Expression drug effects, Glucuronosyltransferase genetics, Glucuronosyltransferase metabolism, Glycosaminoglycans biosynthesis, Glycosaminoglycans metabolism, Humans, Hyaluronan Receptors genetics, Hyaluronan Receptors metabolism, Hyaluronan Synthases, Hyaluronoglucosaminidase genetics, Hyaluronoglucosaminidase metabolism, Propranolol pharmacology, Adrenergic beta-2 Receptor Agonists pharmacology, Asthma metabolism, Glucocorticoids pharmacology, Hyaluronic Acid metabolism, Myocytes, Smooth Muscle metabolism, Respiratory System pathology
- Abstract
Glycosaminoglycans (GAGs), especially hyaluronic acid (HA), regulate tissue flexibility, cell motility, and inflammation. Airway smooth muscle cells (ASMCs) of patients with asthma exhibit abnormal HA metabolism, which contributes to inflammation and remodeling. Here, we investigated the effects of glucocorticoids and long-acting β(2)-agonists (LABAs) on GAG synthesis and HA metabolism by human primary ASMCs. ASMCs were isolated from airway specimens of 10 patients without asthma and 11 patients with asthma. ASMCs were incubated with glucocorticoids, LABAs, or their combination, as well as with their specific receptor antagonists. Secreted and deposited total GAGs were measured by [(3)H]-glucosamine incorporation. The expression of specific GAGs was determined by ELISA and electrophoresis. The expression of HA synthases (HAS), of hyaluronidases (HYALs), and of the HA receptor CD44 was determined by RT-PCR, immunoblotting in cell cultures, and immunohistochemistry in tissue sections of asthmatic lungs. In serum-activated asthmatic ASMCs, glucocorticoids and LABAs significantly inhibited the increased secretion and deposition of total GAGs, but they stimulated secreted and deposited HA of high molecular mass. This effect was attributed to increased mRNA and protein expression of HAS-1 and to the reduced expression of HYAL-1. Furthermore, drug treatment stimulated the expression of CD44 receptors in asthmatic ASMCs. These effects of the drugs were eliminated by their respective receptor inhibitors. Our findings indicate that the combination of glucocorticoids with LABAs counteracts the pathologic degradation of HA, and thereby may reduce the proinflammatory potential of asthmatic ASMCs.
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- 2012
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17. Tenascin-C triggers fibrin accumulation by downregulation of tissue plasminogen activator.
- Author
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Brellier F, Hostettler K, Hotz HR, Ozcakir C, Çöloğlu SA, Togbe D, Ryffel B, Roth M, and Chiquet-Ehrismann R
- Subjects
- Animals, Blotting, Western, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell pathology, Down-Regulation, Embryo, Mammalian cytology, Female, Fibrinolysin metabolism, Fibroblasts cytology, Gene Expression Profiling, Head and Neck Neoplasms metabolism, Head and Neck Neoplasms pathology, Humans, Immunohistochemistry, Lung Diseases metabolism, Lung Diseases pathology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Oligonucleotide Array Sequence Analysis, RNA Interference, Reverse Transcriptase Polymerase Chain Reaction, Tenascin genetics, Tissue Plasminogen Activator genetics, Fibrin metabolism, Fibroblasts metabolism, Tenascin metabolism, Tissue Plasminogen Activator metabolism
- Abstract
We explored novel functions of tenascin-C by comparing mouse embryonic fibroblasts (MEFs) proficient or deficient in tenascin-C expression. Transcript profiling analysis identified tissue plasminogen activator (tPA) as the most consistently over-expressed gene in all tenascin-C deficient MEFs. This was confirmed by real-time PCR as well as by protein expression analysis. In agreement with these observations, tenascin-C deficient MEFs had an increased capacity to digest fibrin in situ. Consistently, tenascin-C expression in vivo was found to correlate with fibrin deposition in several diseases associated with tenascin-C overexpression such as fibrosis, asthma and cancer. In conclusion, the present study suggests a new role of tenascin-C as a regulator of the fibrinolytic system., (Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
18. DMF inhibits PDGF-BB induced airway smooth muscle cell proliferation through induction of heme-oxygenase-1.
- Author
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Seidel P, Goulet S, Hostettler K, Tamm M, and Roth M
- Subjects
- Airway Remodeling drug effects, Airway Remodeling physiology, Becaplermin, Bronchi drug effects, Cells, Cultured, Dimethyl Fumarate, Down-Regulation drug effects, Down-Regulation physiology, Enzyme Induction drug effects, Enzyme Induction physiology, Fumarates pharmacology, Humans, Myocytes, Smooth Muscle drug effects, Proto-Oncogene Proteins c-sis, Bronchi enzymology, Cell Proliferation drug effects, Heme Oxygenase-1 biosynthesis, Myocytes, Smooth Muscle enzymology, Platelet-Derived Growth Factor antagonists & inhibitors, Platelet-Derived Growth Factor pharmacology
- Abstract
Background: Airway wall remodelling is an important pathology of asthma. Growth factor induced airway smooth muscle cell (ASMC) proliferation is thought to be the major cause of airway wall thickening in asthma. Earlier we reported that Dimethylfumarate (DMF) inhibits platelet-derived growth factor (PDGF)-BB induced mitogen and stress activated kinase (MSK)-1 and CREB activity as well as IL-6 secretion by ASMC. In addition, DMF altered intracellular glutathione levels and thereby reduced proliferation of other cell types., Methods: We investigated the effect of DMF on PDGF-BB induced ASMC proliferation, on mitogen activated protein kinase (MAPK) activation; and on heme oxygenase (HO)-1 expression. ASMC were pre-incubated for 1 hour with DMF and/or glutathione ethylester (GSH-OEt), SB203580, hemin, cobalt-protoporphyrin (CoPP), or siRNA specific to HO-1 before stimulation with PDGF-BB (10 ng/ml)., Results: PDGF-BB induced ASMC proliferation was inhibited in a dose-dependant manner by DMF. PDGF-BB induced the phosphorylation of ERK1/2 and p38 MAPK, but not of JNK. DMF enhanced the PDGF-BB induced phosphorylation of p38 MAPK and there by up-regulated the expression of HO-1. HO-1 induction inhibited the proliferative effect of PDGF-BB. HO-1 expression was reversed by GSH-OEt, or p38 MAPK inhibition, or HO-1 siRNA, which all reversed the anti-proliferative effect of DMF., Conclusion: Our data indicate that DMF inhibits ASMC proliferation by reducing the intracellular GSH level with subsequent activation of p38 MAPK and induction of HO-1. Thus, DMF might reduce ASMC and airway remodelling processes in asthma.
- Published
- 2010
- Full Text
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19. Airway epithelium-derived transforming growth factor-beta is a regulator of fibroblast proliferation in both fibrotic and normal subjects.
- Author
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Hostettler KE, Roth M, Burgess JK, Gencay MM, Gambazzi F, Black JL, Tamm M, and Borger P
- Subjects
- Blotting, Western, Cell Proliferation, Cells, Cultured, Enzyme-Linked Immunosorbent Assay, Humans, Respiratory Mucosa immunology, Fibroblasts metabolism, Pulmonary Fibrosis metabolism, Respiratory Mucosa metabolism, Transforming Growth Factor beta metabolism
- Abstract
Background: In the healthy lung, airway epithelial cells (AEC) regulate fibroblast proliferation through release of soluble factors, such as prostaglandins and proteins. Fibroproliferative diseases and airway remodelling may result from an inadequate generation of suppressive factors by AEC or the inability of fibroblasts to respond to them appropriately., Objective: The aim of this study was to study the effect of primary human AEC on the proliferation of fibroblasts obtained from healthy and fibrotic lungs in an interactive cell culture model., Results: Conditioned medium (CM) from 14 out of 16 AEC lines significantly inhibited proliferation of normal human lung fibroblasts by 51.2+/-6.0%. The proliferation of fibroblasts derived from patients with lung fibrosis was equally inhibited by CM of AEC. The inhibitory effect of AEC-CM was completely reversed when fibroblasts were pre-incubated with 2.5 microm indomethacin. Furthermore, primary human AEC, but not fibroblasts, secrete TGF-beta, and the inhibitory effect of the AEC-CM was blocked by neutralizing anti-TGF-beta antibodies., Conclusion: These results demonstrate that AEC actively inhibit the proliferation of both normal and fibrotic fibroblasts via TGF-beta, which induces the prostaglandin E(2) synthesis in fibroblasts. The data indicate that proliferative lung diseases may be treated using the epithelial cell as the target of medication.
- Published
- 2008
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- View/download PDF
20. Dysfunctional interaction of C/EBPalpha and the glucocorticoid receptor in asthmatic bronchial smooth-muscle cells.
- Author
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Roth M, Johnson PR, Borger P, Bihl MP, Rüdiger JJ, King GG, Ge Q, Hostettler K, Burgess JK, Black JL, and Tamm M
- Subjects
- CCAAT-Enhancer-Binding Protein-alpha genetics, Case-Control Studies, Cell Division drug effects, Cells, Cultured, Down-Regulation, Genetic Vectors, Hormone Antagonists pharmacology, Humans, Interleukin-6 biosynthesis, Mifepristone pharmacology, Myocytes, Smooth Muscle cytology, Myocytes, Smooth Muscle drug effects, Oligonucleotides pharmacology, Pulmonary Emphysema metabolism, Signal Transduction drug effects, Transfection, Asthma metabolism, Bronchi cytology, CCAAT-Enhancer-Binding Protein-alpha metabolism, Glucocorticoids pharmacology, Myocytes, Smooth Muscle metabolism, Receptors, Glucocorticoid metabolism
- Abstract
Background: Increased proliferation of bronchial smooth-muscle cells may lead to increased muscle mass in the airways of patients with asthma. The antiproliferative effect of glucocorticoids in bronchial smooth-muscle cells in subjects without asthma is mediated by a complex of the glucocorticoid receptor and the CCAAT/enhancer binding protein alpha (C/EBPalpha). We examined the signaling pathway controlling the inhibitory effect of glucocorticoids on cell proliferation and interleukin-6 synthesis in bronchial smooth-muscle cells of subjects with asthma and those without asthma., Methods: Lines of bronchial smooth-muscle cells were established from cells from 20 subjects with asthma, 8 subjects with emphysema, and 26 control subjects. Cell proliferation was determined by means of cell counts and [3H]thymidine incorporation. Signal transduction was studied by means of an electrophoretic DNA mobility-shift assay, a supershift electrophoretic-mobility assay, immunoblotting, use of C/EBPalpha antisense oligonucleotides, and use of a human C/EBPalpha expression vector. Interleukin-6 release was determined by means of an enzyme-linked immunosorbent assay., Results: Glucocorticoids activated the glucocorticoid receptor and inhibited serum-induced secretion of interleukin-6 in bronchial smooth-muscle cells from both subjects with asthma and those without asthma; however, glucocorticoids inhibited proliferation only in bronchial smooth-muscle cells from subjects without asthma. C/EBPalpha protein was detected by immunoblotting in all bronchial smooth-muscle cells from subjects without asthma but not in those with asthma, whereas the protein was expressed in lymphocytes from both groups of subjects. C/EBPalpha antisense oligonucleotides or the glucocorticoid-receptor inhibitor mifepristone reversed the antiproliferative effect of glucocorticoids in bronchial smooth-muscle cells from subjects without asthma. When bronchial smooth-muscle cells from subjects with asthma were transiently transfected with an expression vector for human C/EBPalpha, two forms of the protein were expressed, and subsequent administration of glucocorticoids inhibited cell proliferation., Conclusions: We hypothesize that a cell-type-specific absence of C/EBPalpha is responsible for the enhanced proliferation of bronchial smooth-muscle cells derived from subjects with asthma and that it explains the failure of glucocorticoids to inhibit proliferation in vitro., (Copyright 2004 Massachusetts Medical Society)
- Published
- 2004
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21. Everolimus and mycophenolate mofetil are potent inhibitors of fibroblast proliferation after lung transplantation.
- Author
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Azzola A, Havryk A, Chhajed P, Hostettler K, Black J, Johnson P, Roth M, Glanville A, and Tamm M
- Subjects
- Adult, Aged, Azathioprine therapeutic use, Bronchi drug effects, Bronchi pathology, Bronchiolitis Obliterans epidemiology, Cells, Cultured, Cyclosporine therapeutic use, Everolimus, Female, Fibroblasts drug effects, Humans, Immunosuppressive Agents pharmacology, Infections epidemiology, Lung Diseases classification, Lung Diseases surgery, Lung Transplantation pathology, Male, Middle Aged, Mycophenolic Acid pharmacology, Postoperative Complications classification, Postoperative Complications microbiology, Sirolimus analogs & derivatives, Sirolimus pharmacology, Tacrolimus therapeutic use, Cell Division drug effects, Fibroblasts cytology, Immunosuppressive Agents therapeutic use, Lung Transplantation immunology, Mycophenolic Acid analogs & derivatives, Sirolimus therapeutic use
- Abstract
Background: Dysregulated fibroblast proliferation is thought to play an important role in the progression of bronchiolitis obliterans (BO) after lung transplantation. Augmented immunosuppression is often used to treat BO. We investigated the effect of methylprednisolone (mPRED), cyclosporine A (CsA), tacrolimus (FK506), azathioprine (AZA), mycophenolate mofetil (MMF), and everolimus (rapamycin derivative [RAD]) on the proliferative capacity of fibroblasts cultured from transbronchial biopsies of lung transplant recipients., Methods: Primary cultures of human lung fibroblasts were obtained from 14 transbronchial biopsies of lung transplant recipients. Subconfluent cells were serum starved for 24 hr followed by growth stimulation in the presence or absence of the respective drug in six concentrations ranging as follows: 0.01 to 100 mg/L for mPRED; 0.01 to 50 mg/L for CsA and AZA; 0.001 to 5 mg/L for FK506 and MMF; and 0.00001 to 1 mg/L for RAD. Proliferation was quantified by [3H]thymidine incorporation and direct cell count. A toxic drug effect was excluded by trypan blue., Results: Drug concentrations (mg/L) causing a 50% inhibition of fibroblast proliferation were mPRED 4; CsA 20; FK506 0.3; AZA 7; MMF 0.3; and RAD 0.0006. Drug concentrations (mg/L) causing inhibition of fetal bovine serum-induced proliferation were mPRED 60; CsA 45; FK506 3; AZA 35; MMF 1; and RAD 0.003., Conclusions: RAD and MMF were the most potent antifibroproliferative drugs and were effective at concentrations achieved clinically, supporting their use for the treatment of patients with early BO. Our method holds promise as an in vitro model to assess the likely in vivo responses of human lung fibroblasts to specific immunosuppressive drugs.
- Published
- 2004
- Full Text
- View/download PDF
22. The influence of shyness on children's test performance.
- Author
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Crozier WR and Hostettler K
- Subjects
- Child, Female, Humans, Individuality, Male, Child Behavior psychology, Educational Measurement, Shyness
- Abstract
Background: Research has shown that shy children differ from their peers not only in their use of language in routine social encounters but also in formal assessments of their language development, including psychometric tests of vocabulary. There has been little examination of factors contributing to these individual differences., Aims: To investigate cognitive-competence and social anxiety interpretations of differences in children's performance on tests of vocabulary. To examine the performance of shy and less shy children under different conditions of test administration, individually with an examiner or among their peers within the familiar classroom setting., Sample: The sample consisted of 240 Year 5 pupils (122 male, 118 female) from 24 primary schools., Method: Shy and less shy children, identified by teacher nomination and checklist ratings, completed vocabulary and mental arithmetic tests in one of three conditions, in a between-subjects design. The conditions varied individual and group administration, and oral and written responses., Results: The conditions of test administration influenced the vocabulary test performance of shy children. They performed significantly more poorly than their peers in the two face-to-face conditions but not in the group test condition. A comparable trend for the arithmetic test was not statistically significant. Across the sample as a whole, shyness correlated significantly with test scores., Conclusions: Shyness does influence children's cognitive test performance and its impact is larger when children are tested face-to-face rather than in a more anonymous group setting. The results are of significance for theories of shyness and have implications for the assessment of schoolchildren.
- Published
- 2003
- Full Text
- View/download PDF
23. Stability of fluoxetine hydrochloride in fluoxetine solution diluted with common pharmaceutical diluents.
- Author
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Peterson JA, Risley DS, Anderson PN, and Hostettler KF
- Subjects
- Chromatography, High Pressure Liquid, Drug Stability, Humans, Pharmaceutical Vehicles chemistry, Solutions chemistry, Fluoxetine chemistry
- Abstract
The stability of fluoxetine hydrochloride in fluoxetine solution diluted with five common pharmaceutical diluents was studied. Fluoxetine syrup, containing fluoxetine 4 mg/mL (as the hydrochloride salt), was diluted to 1 and 2 mg/mL in each of the following: deionized water; Simple Syrup, British Pharmacopeia; Simple Syrup, USP; Aromatic Elixir, USP; and grape-cranberry drink. Each solution was divided into eight 120-mL amber glass bottles: four stored at 5 degrees C and four stored at 30 degrees C. Samples were removed from each bottle at time zero and two, four, and eight weeks and assayed in triplicate with high-performance liquid chromatographic methods for determining fluoxetine concentration and concentration of its primary degradation product, alpha-[2-(methylamino)ethyl]benzene methanol. Stability was established if the fluoxetine concentration changed by < 10% and if the concentration of the degradation product was < 1% of the initial fluoxetine concentration. No test mixture dropped below 95% of the initial fluoxetine concentration or exceeded 0.5% degradation product during the study period. Fluoxetine hydrochloride was stable for eight weeks in fluoxetine solution diluted to 1 or 2 mg/mL with common pharmaceutical diluents and stored at 5 or 30 degrees C.
- Published
- 1994
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