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Kleefeldt JM, Pozarska A, Nardiello C, Pfeffer T, Vadász I, Herold S, Seeger W, Morty RE. Commercially available transfection reagents and negative control siRNA are not inert. Anal Biochem 2020; 606:113828. [PMID: 32745542 DOI: 10.1016/j.ab.2020.113828] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 01/17/2023]
Abstract
The transfection of synthetic small interfering (si)RNA into cultured cells forms the basis of studies that use RNA interference (commonly referred to as "gene knockdown") to study the impact of loss of gene or protein expression on a biological pathway or process. In these studies, mock transfections (with transfection reagents alone), and the use of synthetic negative control (apparently inert) siRNA are both essential negative controls. This report reveals that three widely-used transfection reagents (X-tremeGENE™, HiPerFect, and Lipofectamine® 2000) and five commercially-available control siRNA (from Ambion, Sigma, Santa Cruz, Cell Signaling Technology, and Qiagen) are not inert in cell-culture studies. Both transfection reagents and control siRNA perturbed steady-state mRNA and protein levels in primary mouse lung fibroblasts and in NIH/3T3 cells (a widely-used mouse embryonic fibroblast cell-line), using components of the canonical transforming growth factor-β signaling machinery as a model system. Furthermore, transfection reagents and control siRNA reduced the viability and proliferation of both lung fibroblasts and NIH/3T3 cells. These data collectively provide a cautionary note to investigators to carefully consider the impact of control interventions, such as mock transfections and control siRNA, in RNA interference studies with synthetic siRNA.
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Affiliation(s)
- Jan M Kleefeldt
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany; Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Agnieszka Pozarska
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany; Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Claudio Nardiello
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany; Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Tilman Pfeffer
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany
| | - István Vadász
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Susanne Herold
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Werner Seeger
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany; Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Member of the German Center for Lung Research (DZL), Parkstrasse 1, 60231, Bad Nauheim, Germany; Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus Liebig University, Aulweg 123, 35392, Giessen, Germany.
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Fehl J, Pozarska A, Nardiello C, Rath P, Surate Solaligue DE, Vadász I, Mayer K, Herold S, Seeger W, Morty RE. Control Interventions Can Impact Alveolarization and the Transcriptome in Developing Mouse Lungs. Anat Rec (Hoboken) 2018; 302:346-363. [PMID: 30412359 DOI: 10.1002/ar.23931] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/23/2017] [Accepted: 02/02/2018] [Indexed: 01/20/2023]
Abstract
There is currently much interest in understanding the mechanisms of normal and aberrant lung alveolarization, particularly in the context of bronchopulmonary dysplasia, a common complication of preterm birth where alveolarization is impeded. To this end, the parenteral administration of pharmacological agents that modulate biochemical pathways, or facilitate modulation of gene expression in transgenic animals, has facilitated the discovery and validation of mechanisms that direct lung development. Such studies include control interventions, where the solvent vehicle, perhaps containing an inactive form of the agent applied, is administered; thereby providing a well-controlled point of reference for the analysis of the partner experiment. In the present study, the impact of several widely used control interventions in developing C57Bl/6J mouse pups was examined for effects on lung structure and the lung transcriptome. Parenteral administration of scrambled microRNA inhibitors (called antagomiRs) that are used to control in vivo microRNA neutralization studies, impacted lung volume, septal thickness, and the transcriptome of developing mouse lungs; with some effects dependent upon nucleotide sequence. Repeated intraperitoneal isotonic saline injections altered lung volume, with limited impact on the transcriptome. Parenteral administration of the tamoxifen solvent Miglyol accelerated mouse pup growth, and changed the abundance of 73 mRNA transcripts in the lung. Tamoxifen applied in Miglyol-in the absence of Cre recombinase-decreased pup growth, lung volume, and lung alveolarization and changed the abundance of 298 mRNA transcripts in the lung. These data demonstrate that widely used control interventions can directly impact lung alveolarization and the lung transcriptome in studies on lung development. Anat Rec, 302:346-363, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Joshua Fehl
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Agnieszka Pozarska
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Claudio Nardiello
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Philipp Rath
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - David E Surate Solaligue
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - István Vadász
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Konstantin Mayer
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Susanne Herold
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Werner Seeger
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany
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3
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Affiliation(s)
- Agnieszka Pozarska
- Department of Lung Development and RemodellingMax Planck Institute for Heart and Lung ResearchBad Nauheim, Germanyand
- Department of Internal Medicine (Pulmonology)University of Giessen and Marburg Lung Center, German Center for Lung ResearchGiessen, Germany
| | - Rory E. Morty
- Department of Lung Development and RemodellingMax Planck Institute for Heart and Lung ResearchBad Nauheim, Germanyand
- Department of Internal Medicine (Pulmonology)University of Giessen and Marburg Lung Center, German Center for Lung ResearchGiessen, Germany
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Pozarska A, Rodríguez-Castillo JA, Surate Solaligue DE, Ntokou A, Rath P, Mižíková I, Madurga A, Mayer K, Vadász I, Herold S, Ahlbrecht K, Seeger W, Morty RE. Stereological monitoring of mouse lung alveolarization from the early postnatal period to adulthood. Am J Physiol Lung Cell Mol Physiol 2017; 312:L882-L895. [PMID: 28314804 DOI: 10.1152/ajplung.00492.2016] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/06/2017] [Accepted: 03/08/2017] [Indexed: 11/22/2022] Open
Abstract
Postnatal lung maturation generates a large number of small alveoli, with concomitant thinning of alveolar septal walls, generating a large gas exchange surface area but minimizing the distance traversed by the gases. This demand for a large and thin gas exchange surface area is not met in disorders of lung development, such as bronchopulmonary dysplasia (BPD) histopathologically characterized by fewer, larger alveoli and thickened alveolar septal walls. Diseases such as BPD are often modeled in the laboratory mouse to better understand disease pathogenesis or to develop new interventional approaches. To date, there have been no stereology-based longitudinal studies on postnatal mouse lung development that report dynamic changes in alveoli number or alveolar septal wall thickness during lung maturation. To this end, changes in lung structure were quantified over the first 22 mo of postnatal life of C57BL/6J mice. Alveolar density peaked at postnatal day (P)39 and remained unchanged at 9 mo (P274) but was reduced by 22 mo (P669). Alveoli continued to be generated, initially at an accelerated rate between P5 and P14, and at a slower rate thereafter. Between P274 and P669, loss of alveoli was noted, without any reduction in lung volume. A progressive thinning of the alveolar septal wall was noted between P5 and P28. Pronounced sex differences were observed in alveoli number in adult (but not juvenile) mice, when comparing male and female mouse lungs. This sex difference was attributed exclusively to the larger volume of male mouse lungs.
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Affiliation(s)
- Agnieszka Pozarska
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - José Alberto Rodríguez-Castillo
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - David E Surate Solaligue
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Aglaia Ntokou
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Philipp Rath
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and
| | - Ivana Mižíková
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Alicia Madurga
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Konstantin Mayer
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - István Vadász
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Susanne Herold
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Katrin Ahlbrecht
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Werner Seeger
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and.,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; and .,Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, member of the German Center for Lung Research, Giessen, Germany
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Silva DMG, Nardiello C, Pozarska A, Morty RE. Recent advances in the mechanisms of lung alveolarization and the pathogenesis of bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1239-72. [PMID: 26361876 DOI: 10.1152/ajplung.00268.2015] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 09/09/2015] [Indexed: 02/08/2023] Open
Abstract
Alveolarization is the process by which the alveoli, the principal gas exchange units of the lung, are formed. Along with the maturation of the pulmonary vasculature, alveolarization is the objective of late lung development. The terminal airspaces that were formed during early lung development are divided by the process of secondary septation, progressively generating an increasing number of alveoli that are of smaller size, which substantially increases the surface area over which gas exchange can take place. Disturbances to alveolarization occur in bronchopulmonary dysplasia (BPD), which can be complicated by perturbations to the pulmonary vasculature that are associated with the development of pulmonary hypertension. Disturbances to lung development may also occur in persistent pulmonary hypertension of the newborn in term newborn infants, as well as in patients with congenital diaphragmatic hernia. These disturbances can lead to the formation of lungs with fewer and larger alveoli and a dysmorphic pulmonary vasculature. Consequently, affected lungs exhibit a reduced capacity for gas exchange, with important implications for morbidity and mortality in the immediate postnatal period and respiratory health consequences that may persist into adulthood. It is the objective of this Perspectives article to update the reader about recent developments in our understanding of the molecular mechanisms of alveolarization and the pathogenesis of BPD.
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Affiliation(s)
- Diogo M G Silva
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Claudio Nardiello
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Agnieszka Pozarska
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rory E Morty
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
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Madurga A, Golec A, Pozarska A, Ishii I, Mižíková I, Nardiello C, Vadász I, Herold S, Mayer K, Reichenberger F, Fehrenbach H, Seeger W, Morty RE. The H2S-generating enzymes cystathionine β-synthase and cystathionine γ-lyase play a role in vascular development during normal lung alveolarization. Am J Physiol Lung Cell Mol Physiol 2015; 309:L710-24. [PMID: 26232299 DOI: 10.1152/ajplung.00134.2015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 07/24/2015] [Indexed: 12/19/2022] Open
Abstract
The gasotransmitter hydrogen sulfide (H2S) is emerging as a mediator of lung physiology and disease. Recent studies revealed that H2S administration limited perturbations to lung structure in experimental animal models of bronchopulmonary dysplasia (BPD), partially restoring alveolarization, limiting pulmonary hypertension, limiting inflammation, and promoting epithelial repair. No studies have addressed roles for endogenous H2S in lung development. H2S is endogenously generated by cystathionine β-synthase (Cbs) and cystathionine γ-lyase (Cth). We demonstrate here that the expression of Cbs and Cth in mouse lungs is dynamically regulated during lung alveolarization and that alveolarization is blunted in Cbs(-/-) and Cth(-/-) mouse pups, where a 50% reduction in the total number of alveoli was observed, without any impact on septal thickness. Laser-capture microdissection and immunofluorescence staining indicated that Cbs and Cth were expressed in the airway epithelium and lung vessels. Loss of Cbs and Cth led to a 100-500% increase in the muscularization of small- and medium-sized lung vessels, which was accompanied by increased vessel wall thickness, and an apparent decrease in lung vascular supply. Ablation of Cbs expression using small interfering RNA or pharmacological inhibition of Cth using propargylglycine in lung endothelial cells limited angiogenic capacity, causing a 30-40% decrease in tube length and a 50% decrease in number of tubes formed. In contrast, exogenous administration of H2S with GYY4137 promoted endothelial tube formation. These data confirm a key role for the H2S-generating enzymes Cbs and Cth in pulmonary vascular development and homeostasis and in lung alveolarization.
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Affiliation(s)
- Alicia Madurga
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Anita Golec
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Agnieszka Pozarska
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Isao Ishii
- Keio University Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Ivana Mižíková
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Claudio Nardiello
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - István Vadász
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Susanne Herold
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany
| | - Konstantin Mayer
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany
| | - Frank Reichenberger
- Department of Pulmonology, Asklepios Lung Centre, Munich-Gauting, Germany; and
| | - Heinz Fehrenbach
- Division of Experimental Pneumology, Priority Area Asthma and Allergy, Airway Research Center North, German Center for Lung Research, Borstel, Germany
| | - Werner Seeger
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rory E Morty
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center, German Center for Lung Research, Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany;
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Pozarska A, da Costa Mathews C, Wong M, Pencheva K. Application of COSMO-RS as an excipient ranking tool in early formulation development. Eur J Pharm Sci 2013; 49:505-11. [DOI: 10.1016/j.ejps.2013.04.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/20/2013] [Accepted: 04/15/2013] [Indexed: 10/26/2022]
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