Pulmonary Function Tests Versus Computed Tomography in Sheep With Experimental Emphysema

Hoffman, Andrew M.; Tsai, Larry; Mazan, Melissa R.; Bellardine, Carissa; Bell, Allison; Lutchen, K.R.; Ingenito, Edward P.

doi:10.1080/019021490944241

Cited by 3 publications

(2 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lung physiology assessments included measurements of lung resistance ( R L ), dynamic compliance ( C L ), and quasistatic deflation pressure–volume curves summarized using the exponential equation V(P) = V max – ( V max – V min ) e –kP , where V is volume, P is pressure, V max is lung volume at infinite inflation pressure, V min is lung volume at 0 inflation pressure, and k is the shape factor describing the curvature of the exponential. Measurements were performed in anesthetized intubated animals as previously described (9,12).…”

Section: Methodsmentioning

confidence: 99%

Autologous Lung-Derived Mesenchymal Stem Cell Transplantation in Experimental Emphysema

et al. 2012

Self Cite

View full text Add to dashboard Cite

Autologous lung-derived mesenchymal stem cells (LMSCs) were transplanted endoscopically into sheep with experimental emphysema to assess their capacity to regenerate functional tissue. LMSC lines were derived from transbronchial biopsies, cloned at passage 2, expanded in culture, and labeled. A delivery scaffold containing 1% fibrinogen, 20 µg/ml of fibronectin, and 20 µg/ml of poly-L-lysine was used to promote cell attachment and spreading. Treatment animals received scaffold containing 5-10 × 10 6 cells/ site; control animals received scaffold alone. Phenotypic markers, differentiation capacity, extracellular matrix protein expression, and paracrine function of LMSCs were characterized in vitro. Responses to LMSC transplantation in vivo were assessed in terms of clinical toxicity, lung physiology, change in tissue mass (measured by CT scanning) and perfusion (measured by scintigraphy scanning), and tissue histology. At 4-week follow-up, transplants were well tolerated and associated with increased tissue mass and lung perfusion compared to control treatment. Histology confirmed cell retention, increased cellularity, and increased extracellular matrix content following LMSC treatment. Labeled cells were distributed in the alveolar septum and peribronchiolar interstitium. Some label was also present within phagocytes, indicating that a fraction of autologous LMSCs do not survive transplantation. These results suggest that endobronchial delivery of autologous LMSCs has potential therapeutic utility for regenerating functional lung in emphysema.

show abstract

Section: Methodsmentioning

confidence: 99%

Autologous Lung-Derived Mesenchymal Stem Cell Transplantation in Experimental Emphysema

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…In this study, we used the latter bronchoscopic technique to measure collateral ventilation in a sheep model of emphysema previously shown to exhibit physiologic changes consistent with mild-to-moderate emphysema including a 60–86% increase in RV, 35–36% decrease in DLco, and a 32% increase in chord compliance [11, 12]. We hypothesized that emphysema would be associated with decreased collateral resistance, and that the degree of change would correlate with the regional severity of alveolar destruction.…”

Section: Introductionmentioning

confidence: 99%

Bronchoscopic Measurement of Collateral Ventilation in a Sheep Model of Emphysema

Tsai

Hoffman²,

Mazan³

et al. 2007

Respiration

View full text Add to dashboard Cite

Background: The development of bronchoscopic therapies for emphysema has renewed interest in collateral ventilation. The success or failure of bronchoscopically placed valves or biologic glues may be determined by collateral ventilation, which is exaggerated in emphysema. Furthermore, the validity of various animal models of emphysema for testing such techniques must be understood in the context of their species-specific collateral ventilation. Objectives: To quantify collateral ventilation in a sheep model of emphysema using a simple in vivo bronchoscopic method. Methods: Collateral ventilation was measured in 8 anesthetized sheep using a simple method which measured pressure and flow through the working channel of a bronchoscope wedged in a segmental lung orifice. Animals then underwent nebulized papain treatments to generate emphysema, followed by repeat bronchoscopic measurements. Results: There was a 33% decrease in resistance to collateral ventilation following papain treatment. Changes in collateral resistance were closely correlated with disease severity as measured by changes in segmental compliance, which increased 267%. Conclusions: Collateral ventilation is significantly increased in sheep following nebulized papain. Bronchoscopic measurement of collateral ventilation may be useful for evaluating other animal models of emphysema and for predicting the response to bronchoscopic therapies in human emphysema patients.

show abstract

Living with lung disease: experimental models to assess the long-term effects of prematurity

Evans

Pillow

Simpson

et al. 2022

American Journal of Physiology-Lung Cellular and Molecular Phys

View full text Add to dashboard Cite

Laboratory models provide an important tool in helping to understand the cellular and molecular drivers of respiratory disease. Many animal models exist that model the neonatal outcomes of preterm birth. Discoveries at the laboratory bench from examination of both human tissue and tissues from animal models have informed the life-saving technologies and clinical care used today. Yet animal laboratory models of preterm birth have rarely been utilized beyond the neonatal period, despite growing reports of respiratory symptoms and subnormal lung function throughout childhood. Elucidation of the driving factors and physiological explanations underpinning poor outcomes in survivors of preterm birth are crucial to optimize clinical care and identify therapeutic targets. Can existing neonatal models be utilized to study respiratory outcomes beyond infancy? This review answers the question by highlighting the clinical evidence underpinning an active respiratory disease process after preterm birth and exploring the benefits and drawbacks of existing models to conduct research into the long-term respiratory outcomes of preterm birth.

show abstract

Pulmonary Function Tests Versus Computed Tomography in Sheep With Experimental Emphysema

Cited by 3 publications

References 47 publications

Autologous Lung-Derived Mesenchymal Stem Cell Transplantation in Experimental Emphysema

Autologous Lung-Derived Mesenchymal Stem Cell Transplantation in Experimental Emphysema

Bronchoscopic Measurement of Collateral Ventilation in a Sheep Model of Emphysema

Living with lung disease: experimental models to assess the long-term effects of prematurity

Contact Info

Product

Resources

About