Swine Lung Research Articles

Genetic diversity of influenza A viruses circulating in pigs between winter and summer in a Minnesota live animal market.

There has been little surveillance of influenza A viruses (IAVs) circulating in swine at live animal markets, particularly in the United States. To address this gap, we conducted active surveillance of IAVs in pigs, the air, and the environment during a summer and winter season in a live animal market in St. Paul, Minnesota, that had been epidemiologically associated with swine-origin influenza cases in humans previously. High rates of IAV were detected by PCR in swine lungs and oral fluids during both summer and winter seasons. Rates of IAV detection by PCR in the air were similar during summer and winter, although rates of successful virus isolation in the air were lower during summer than in winter (26% and 67%, respectively). H3N2 was the most prevalent subtype in both seasons, followed by H1N2. Genetically diverse viruses with multiple gene constellations were isolated from both winter and summer, with a total of 19 distinct genotypes identified. Comparative phylogenetic analysis of all eight segments of 40 virus isolates from summer and 122 isolates from winter revealed that the summer and winter isolates were genetically distinct, indicating IAVs are not maintained in the market, but rather are re-introduced, likely from commercial swine. These findings highlight the extent of IAV genetic diversity circulating in swine in live animal markets, even during summer months, and the ongoing risk to humans.

Homologous and heterologous assessment of a novel biomaterial for venous patch

ObjectiveThis study evaluated swine and bovine pulmonary visceral pleura (PVP) as a vascular patch. Venous patches are frequently used in surgery for repair or reconstruction of veins. Autologous patches are often limited by the number and dimension of donor tissue and can result in donor complications. Bovine pericardium is the most common heterologous patch used by vascular surgeons. Researchers, however, are continually seeking to improve heterologous and synthetic patches for improved outcome. MethodsThe PVP was peeled from swine and bovine lungs and cross-linked with glutaraldehyde. After sterilization and rinsing, the PVP patches were implanted in the jugular vein (10 × 35 mm) of pigs and dogs. Patency was evaluated by ultrasound, and animals were euthanized at 2 and 4 months. Neoendothelium and neomedia were evaluated by histologic analysis. ResultsThe jugular vein patched by PVP in pigs and dogs remained patent at 2 and 4 months with no adhesions, inflammation, or aneurysm in the patches. The biomarkers of endothelial cells—factor VIII, platelet/endothelial cell adhesion molecule 1, and endothelial nitric oxide synthase—were detected in the neoendothelial cells. The expression of vascular smooth muscle cell (VSMC) α-actin was robust in the neomedia at 2 and 4 months. Neomedia composed of VSMCs developed to nearly double the thickness of adjacent jugular vein. The circumferential orientation of VSMCs in neomedia further increased in the 4-month group. ConclusionsThe cross-linked swine and bovine PVP patch has a nonthrombogenic surface that maintains patency. The PVP patch may overcome the pitfall of compliance mismatch of synthetic patches. The proliferation of vascular cells assembled in the neoendothelium and neomedia in the patches may support long-term patency.

Quantification of lung surface wave speed in a water-filled lung: An ex vivo swine lung study

Lung edema is a common symptom of congestive heart failure and inflammatory conditions, such as acute respiratory distress syndrome. Currently, computed tomography (CT) is considered the standard to assess lung edema, but it requires ionizing radiation and poses a significant logistic burden. Lung ultrasound (LUS) has previously been used to assess lung edema using ultrasound B-line artifacts, but analysis of the B-line artifacts relies on visual interpretation. We developed lung ultrasound surface wave elastography (LUSWE) to measure lung surface wave speed safely. This project aims to evaluate LUSWE to quantify lung surface wave speed in an ex vivo water-filled swine lung. The lung surface wave speeds were measured at baseline and at frequencies of 100 Hz, 200 Hz, 300 Hz, and 400 Hz. Then, an amount of water was filled into the lung through its trachea. Ultrasound imaging was used to guide the water filling until significant changes were visible on the imaging. The lung surface wave speeds were measured. An additional 120 ml of water was then filled into the lung. The lung surface wave speeds were measured again. The results demonstrated that the lung surface wave speed decreased with respect to water content.Lung edema is a common symptom of congestive heart failure and inflammatory conditions, such as acute respiratory distress syndrome. Currently, computed tomography (CT) is considered the standard to assess lung edema, but it requires ionizing radiation and poses a significant logistic burden. Lung ultrasound (LUS) has previously been used to assess lung edema using ultrasound B-line artifacts, but analysis of the B-line artifacts relies on visual interpretation. We developed lung ultrasound surface wave elastography (LUSWE) to measure lung surface wave speed safely. This project aims to evaluate LUSWE to quantify lung surface wave speed in an ex vivo water-filled swine lung. The lung surface wave speeds were measured at baseline and at frequencies of 100 Hz, 200 Hz, 300 Hz, and 400 Hz. Then, an amount of water was filled into the lung through its trachea. Ultrasound imaging was used to guide the water filling until significant changes were visible on the imaging. The lung surface wave speeds were measured...

A Pilot Study of Wet Lung Using Lung Ultrasound Surface Wave Elastography in an Ex Vivo Swine Lung Model.

Extravascular lung water (EVLW) is a basic symptom of congestive heart failure and other conditions. Computed tomography (CT) is standard to assess EVLW, but it requires ionizing radiation and radiology facilities. Lung ultrasound reverberation artifacts called B-lines have been used to assess EVLW. However, B-line artifact analysis relies on visual interpretation and subjects to inter-observer variability. We developed lung ultrasound surface wave elastography (LUSWE) to measure lung surface wave speed. This research aims to develop LUSWE to measure the change of lung surface wave speed due to lung water in an ex vivo swine lung model. The surface wave speeds of a fresh ex vivo swine lung were measured at four frequencies of 100 Hz, 200 Hz, 300 Hz, and 400 Hz. An amount of water was then filled into the lung through its trachea. Ultrasound imaging was used to guide the water filling until significant changes were visible on the imaging. The lung surface wave speeds were measured. An additional 120 ml of water was then filled into the lung. The lung surface wave speeds were then measured again. The results demonstrated that the lung surface wave speed decreased with respect to water content.

Occurrence of Mycoplasma hyopneumoniae in slaughter pigs from Southern Brazil

Mycoplasma hyopneumoniae is the causative agent of enzootic pneumonia (EP), a disease that is highly prevalent and globally distributed, causing significant economic losses to the swine industry. Disease progression is characterized by reduced feed conversion and the development of lung lesions. Considering the limited information about the epidemiology of EP in Southern Brazil, the main objective of this study was to determine the occurrence of M. hyopneumoniae in swine lung samples and to evaluate the scores of lung lesions caused by local strains. A total of 120 samples was randomly collected and processed. DNA was extracted from lung tissue to perform nested-PCR and lungs were inspected to evaluate the presence of the pneumonia-like gross lesions of M. hyopneumoniae. The results showed 95.8% positive samples, while the lung lesion score analysis showed suggestive lesions in 60% of samples. The detection of positive samples in nested-PCR was associated with the presence of pneumonia-like gross lesions (P < 0.01). The results demonstrate a high occurrence of EP in slaughter pigs from southern Brazil.

Antimicrobial susceptibility of pathogenic bacteria isolated from swine lungs

Antimicrobial susceptibility of pathogenic bacteria isolated from swine lungs

Karakteristik Pasteurella multocida Penyebab Pasteurellosis pada Babi di Kota Kupang Provinsi Nusa Tengggara Timur

The number of commercial pigs in East Nusa Tenggara has grown fast with a population of 1,739,481, and has become more potential. However, the mixed farming model has become one of the factor of potentially high in the transmission of disease-causing pathogenic microorganisms. One of the microorganism is Pasteurella multocida which causes pasteurellosis, has been identified in 25% of slaughtered pigs (Maes et al., 2001). One of the clinical symptom due to pasteurellosis in pigs is the occurrence of bronchopneumonia in pulmo and inflammation in various visceral organs, such as the heart and kidneys. the phenotypic characteristization of this bacteria, will be very helpful in designing a comprehensive prevention and treatment programs of pig pasteurellosis.
 The aim of the research was to determine the characteristics of P. multocida related to pasteurellosis and recording of the disease in Kupang, NTT. This research also find out the phenotipyc characteristics of P. multocida species from pigs and the possibility of transmission among sensitive species.
 A total of 30 swine lung samples of pulmo were obtained from slaughterhouse in Kupang to carry out this study. Pulmo taken from slaughtered pigs that showed clinical respiratoric symptoms such as dyspnoea and the presence of serous to mucopurulent nasal exudates, and the specific lesions of gray hepatization in pulmo. The collected samples were then processed for histopathological and microbiological studies.
 Out of the total 30 sample, 15 samples were found to be suspected for pasteurellosis, and 3 samples were successfully confirmed to be positive for Pasteurella multocida. Varied macroscopic changes showed pathognomonic lesions as multifocal hemorrhage and congestion of the pulmonary lobes. Serous to mucopurulent exudate were found in lumen bronchus. Multi lobes grayed hepatization and multifocal hemorrhage were observed in the pulmo. Histopatologic analysis showed three types of pneumonia that were multifocal suppurative bronchopneumonia with neutrophil infiltration into alveoli and bronchioles; non-suppurative pneumonia as fibrinous bronchopneumonia with severe congestion, and chronic bronchiolitis with infiltration of mononuclear cell and thickening of fibrous tissue on bronchioles. Bacterial culture from the samples showed circular, convex and non hemolytic colony on blood agar base. Gram staining’s showed Gram negative microorganism with coccoid bipolar structure, which are some of the characteristic of the microorganism..
 It was concluded that the samples is having P. multocida infection. Although, some isolate on MacConkey showed lactose fermentation and tolerance to bile salts that were not the nature of the microorganism, isolation and identification from other organs needed to be done, for example from the heart and kidneys, are needed.

Direct detection of Actinobacillus pleuropneumoniae in swine lungs and tonsils by real-time recombinase polymerase amplification assay

Actinobacillus pleuropneumoniae is the etiological agent of swine contagious pleuropneumoniae, which is distributed globally and associated with severe economic losses in the pig rearing industry. In this study, a real-time recombinase polymerase amplification assay (real-time RPA) based on the apxIVA gene was developed to rapid detect A. pleuropneumoniae. Real-time RPA was performed successfully in Genie III at the constant temperature of 39 °C for 20 min. The developed assay was highly specific for A. pleuropneumoniae, and the sensitivity at 95% probability was 536 fg of A. pleuropneumoniae genomic DNA. The real-time RPA for A. pleuropneumoniae was further evaluated on the 112 clinical swine lung and tonsil samples, and 25 (22.3%), 27 (24.1%), and 12 (10.7%) samples were positive for A. pleuropneumoniae by the real-time RPA, real-time PCR and bacterial isolation, respectively. With a real-time PCR as the reference method, the real-time RPA showed a diagnostic specificity of 98.8%, a diagnostic sensitivity of 88.9%, a positive predicative value of 96.0%, a negative predictive value of 96.5%, and a kappa value of 0.900. The above data demonstrated the well potentiality and usefulness of the developed real-time RPA assay in the reliable detection of A. pleuropneumoniae, especially in resource limited settings.

Rodents Versus Pig Model for Assessing the Performance of Serotype Chimeric Ad5/3 Oncolytic Adenoviruses.

Oncolytic adenoviruses (Ad) are promising tools for cancer therapeutics. Most Ad-based therapies utilize species C serotypes, with Adenovirus type 5 (Ad5) most commonly employed. Prior clinical trials demonstrated low efficiency of oncolytic Ad5 vectors, mainly due to the absence of Ad5 primary receptor (Coxsackie and Adenovirus Receptor, CAR) on cancer cells. Engineering serotype chimeric vectors (Ad5/3) to utilize Adenovirus type 3 (Ad3) receptors has greatly improved their oncolytic potential. Clinical translation of these infectivity-enhanced vectors has been challenging due to a lack of replication permissive animal models. In this study, we explored pigs as a model to study the performance of fiber-modified Ad5/3 chimeric vectors. As a control, the Ad5 fiber-unmodified virus was used. We analyzed binding, gene transfer, replication, and cytolytic ability of Ad5 and Ad5/3 in various non-human cell lines (murine, hamster, canine, porcine). Among all tested cell lines only porcine cells supported active binding and replication of Ad5/3. Syrian hamster cells supported Ad5 replication but showed no evidence of productive viral replication after infection with Ad5/3 vectors. Transduction and replication ability of Ad5/3 in porcine cells outperformed Ad5, a phenomenon often observed in human cancer cell lines. Replication of Ad5 and Ad5/3 was subsequently evaluated in vivo in immunocompetent pigs. Quantitative PCR analyses 7 days post infection revealed Ad5 and Ad5/3 DNA and replication-dependent luciferase activity in the swine lungs and spleen indicating active replication in these tissues. These studies demonstrated the flaws in using Syrian hamsters for testing serotype chimeric Ad5/3 vectors. This is the first report to validate the pig as a valuable model for preclinical testing of oncolytic adenoviruses utilizing Adenovirus type 3 receptors. We hope that these data will help to foster the clinical translation of oncolytic adenoviruses including those with Ad3 retargeted tropism.

Ethyl pyruvate reduces organic dust-induced airway inflammation by targeting HMGB1-RAGE signaling

BackgroundAnimal production workers are persistently exposed to organic dust and can suffer from a variety of respiratory disease symptoms and annual decline in lung function. The role of high mobility group box-1 (HMGB1) in inflammatory airway diseases is emerging. Hence, we tested a hypothesis that organic dust exposure of airway epithelial cells induces nucleocytoplasmic translocation of HMGB1 and blocking this translocation dampens organic dust-induced lung inflammation.MethodsRats were exposed to either ambient air or swine barn (8 h/day for either 1, 5, or 20 days) and lung tissues were processed for immunohistochemistry. Swine barn dust was collected and organic dust extract (ODE) was prepared and sterilized. Human airway epithelial cell line (BEAS-2B) was exposed to either media or organic dust extract followed by treatment with media or ethyl pyruvate (EP) or anti-HMGB1 antibody. Immunoblotting, ELISA and other assays were performed at 0 (control), 6, 24 and 48 h. Data (as mean ± SEM) was analyzed using one or two-way ANOVA followed by Bonferroni’s post hoc comparison test. A p value of less than 0.05 was considered significant.ResultsCompared to controls, barn exposed rats showed an increase in the expression of HMGB1 in the lungs. Compared to controls, ODE exposed BEAS-2B cells showed nucleocytoplasmic translocation of HMGB1, co-localization of HMGB1 and RAGE, reactive species and pro-inflammatory cytokine production. EP treatment reduced the ODE induced nucleocytoplasmic translocation of HMGB1, HMGB1 expression in the cytoplasmic fraction, GM-CSF and IL-1β production and augmented the production of TGF-β1 and IL-10. Anti-HMGB1 treatment reduced ODE-induced NF-κB p65 expression, IL-6, ROS and RNS but augmented TGF-β1 and IL-10 levels.ConclusionsHMGB1-RAGE signaling is an attractive target to abrogate OD-induced lung inflammation.

Development and characterization of swine primary respiratory epithelial cells and their susceptibility to infection by four influenza virus types

Influenza viruses are a group of respiratory pathogens that have evolved into four different types: A, B, C, and D. A common feature is that all four types are capable of replicating and transmitting among pigs. Here, we describe the development of isogenous cell culture system from the swine respiratory tract to study influenza viruses. Phenotypic characterization of swine primary nasal turbinate, trachea and lung cells revealed high expression of cytokeratin and demonstrated tissue site dependent expression of tight junction proteins. Furthermore, lectin binding assay on these cells demonstrated higher levels of Sia2–6Gal than Sia2–3Gal receptors and supported the replication of influenza A, B, C, and D viruses to appreciable levels at both 33 and 37 °C, but replication competence was dependent on virus type or temperature used. Overall, these swine primary respiratory cells showed epithelial phenotype, which is suitable for studying the comparative biology and pathobiology of influenza viruses.

Microbial communities in swine lungs and their association with lung lesions.

SummaryUnder natural farming, environmental pathogenic microorganisms may invade and affect swine lungs, further resulting in lung lesions. However, few studies on swine lung microbiota and their potential relationship with lung lesions were reported. Here, we sampled 20 pigs from a hybrid herd raised under natural conditions; we recorded a lung‐lesion phenotype and investigated lung microbial communities by sequencing the V3‐V4 region of 16S rRNA gene for each individual. We found reduced microbial diversity but more biomass in the severe‐lesion lungs. Methylotenera, Prevotella, Sphingobium and Lactobacillus were the prominent bacteria in the healthy lungs, while Mycoplasma, Ureaplasma, Sphingobium, Haemophilus and Phyllobacterium were the most abundant microbes in the severe‐lesion lungs. Notably, we identified 64 lung‐lesion‐associated OTUs, of which two classified to Mycoplasma were positively associated with lung lesions and 62 showed negative association including thirteen classified to Prevotella and six to Ruminococcus. Cross‐validation analysis showed that lung microbiota explained 23.7% phenotypic variance of lung lesions, suggesting that lung microbiota had large effects on promoting lung healthy. Furthermore, 22 KEGG pathways correlated with lung lesions were predicted. Altogether, our findings improve the knowledge about swine lung microbial communities and give insights into the relationship between lung microbiota and lung lesions.

Initial experience with transbronchial cryoablation as a novel local treatment for malignant peripheral lung lesions

IntroductionPercutaneous cryoablation has been adopted for small, malignant peripheral pulmonary lesions and has yielded favourable results as a less invasive local treatment. A transbronchial approach may reduce the risks of...

Diets of animal origin and their influence on the development of the immatures of Chrysomya albiceps (Diptera: Calliphoridae): implications for forensic entomology

AbstractIn forensic entomology, the minimum and maximum post‐mortem interval (PMI) is estimated on the basis of the developmental stages of necrophagous Diptera larvae on a corpse. The nutritional composition of the decomposing tissue, which can influence larval development rates, may impact the precision of this estimate. We compared the post‐embryonic development of Chrysomya albiceps reared on bovine muscle and swine lung. Forty newly hatched fly larvae, per treatment, were placed on 60 g of the following tissues: bovine muscle (control) and swine lung (T1). Each treatment had three replicates. The experiments were maintained under controlled conditions (28°C day/26°C night, 70 ± 10% RH and 12 h photophase). Flies reared on bovine muscle took significantly longer to complete their larval phase (8.1 days) than did larvae reared on swine lung (6.8 days). The total duration of development in bovine muscle was significantly slower (12.3 days) than in swine lung. Larvae that were reared on swine lungs were significantly heavier than larvae reared on bovine muscle. Total larval viability was high on pig lung (over 49%). The sex ratio was closer to the 1:1 ratio in bovine muscle (rs = 0.55), with a slightly greater proportion of female larvae. The percentage of abnormality remained within the predicted range. The results show that the different tissues influenced larval development. This underlines the importance of considering the type of cadaveric tissue when larval development is used to calculate the minimum PMI in forensic investigations.

Development of Water Content Dependent Tissue Dielectric Property Models.

We propose dielectric tissue property models dependent on both water and air content covering the microwave frequency range. Water is the largest constituent of biological tissues and its effect on the dielectric properties of biological tissue has been studied. However, dehydration effects due to thermal heating have not been fully characterized. We combined 1) Maxwell-Fricke mixture theory with a four-pole Cole-Cole equation to include water and air content dependency and as the second approach a different 2) Maxwell mixture model was coupled with a Debye function. The proposed approaches (1 and 2) were able to predict the permittivity (ε') and conductivity (σ) of bovine liver and swine lung tissues at different hydration and inflation states from 1-15 GHz. A second approach coupling Maxwell and Debye models required fewer assumptions and modelled tissue properties with higher accuracy (less than 15% mean percent error in all tissue types). These models may help improve the accuracy of microwave ablation simulation when tissue water content changes as a result of vaporization, and may facilitate personalized treatment planning.

TRANSLATION OF A NOVEL 3D NAVIGATION AUGMENTED FLUOROSCOPY APPROACH FOR ENDOBRONCHIAL PROCEDURES BASED ON CBCT

SESSION TITLE: Interventional Pulmonology Investigations SESSION TYPE: Original Investigations PRESENTED ON: 10/10/2018 03:45 PM - 04:45 PM PURPOSE: To develop and characterize a novel navigation approach for endobronchial procedures based on Cone Beam Computed Tomography (CBCT) and Augmented Fluoroscopy from bench to bedside. METHODS: An endobronchial navigation software prototype was developed that can generate a 3D airway segmentation, tumor segmentation and 3D airway navigation path planning based on CBCT (XperCT, Philips), without electromagnetic (EM) tracking. All models (airways, targets, pathways) can be superimposed on X-ray to generate an augmented fluoroscopy view with real-time updates based upon table motion, magnification, or C-arm rotation. The navigation prototype was characterized and optimized using non-bronchoscopy devices (endovascular guidewires, catheters and steerable sheaths) in bench models (a 3D printed airway and an ex vivo breathable swine lung) and in an animal model (swine, n=3, approved by Animal Care and Use Committee). Two operators were asked to navigate to predefined lung segments and locations were confirmed with CBCT and 2D X-ray at two orthogonal angles. 9 complex clinical transbronchial biopsies of parenchymal lung lesions were retrospective reported (under an IRB-approved clinical protocol) using combinations of fluoroscopy, augmented fluoroscopy, CBCT, CBCT derived 3D models, EM navigation, and finally off-label miniature hardware without direct optical endoscopy. Clinical cases used previously FDA cleared software (OncoSuite, Philips), off-label for lung applications, whereas pre-clinical studies utilized a prototype software specific for lung. RESULTS: In the bench model, 10/10 (100%) navigation tasks were successful. In the animal model, navigation success was 21/24 targets (87%). In the clinical case series, CBCT and augmented fluoroscopy enabled correct guidance of the bronchoscope to peripheral and central lung lesions for biopsy. 8/9 (88.9%) patients, had accurate on-target navigation confirmed via CBCT and/or by histopathological or microbiological results. Pulmonologists found that the lesion segmentation was helpful in 9 of 9 cases (100%), including in 3 cases with fluoroscopic invisible/obscured lesions. The 9th case that failed with EM tracking with conventional guidance and CBCT guidance was successfully biopsied (confirmed with CBCT) using an off-label endovascular steerable sheath and a standard bronchoscopy aspirating needle without bronchoscopic navigation. CONCLUSIONS: CBCT derived 3D road mapping navigation for bronchoscopic procedures using augmented fluoroscopy is feasible and may be used with or without optical bronchoscopic tools. The impact upon workflow, outcomes, and cost are undefined as are the potential roles for these tools in clinical care. CLINICAL IMPLICATIONS: Real time derived navigation tools, such as CBCT image guidance and augmented fluoroscopy, may complement bronchial navigation for small and difficult to access peripheral lung nodules. DISCLOSURES: PI on grant to UCI relationship with Philips Healthcare Please note: $20001 - $100000 Added 06/03/2018 by Nadine Abi-Jaoudeh, source=Web Response, value=money to UCI Pi on grant to UCI relationship with Teclison Cheery Pharma Please note: >$100000 Added 06/03/2018 by Nadine Abi-Jaoudeh, source=Web Response, value=grant to UCI PI on grant to UCI relationship with Sillajen Please note: $5001 - $20000 Added 06/03/2018 by Nadine Abi-Jaoudeh, source=Web Response, value=grant money to UCI no disclosure on file for Robert Browning; No relevant relationships by Quirina de Ruiter, source=Web Response no disclosure on file for Joseph Fontana; No relevant relationships by john karanian, source=Web Response CRADA between NIH and Philips relationship with Philips Healthcare Please note: >$100000 Added 06/11/2018 by William Pritchard, source=Web Response, value=Grant/Research Support No relevant relationships by Alessandro Radaelli, source=Web Response No relevant relationships by Stephanie Schampaert, source=Web Response Employee relationship with Philips Please note: >$100000 Added 06/04/2018 by Imramsjah van der Bom, source=Web Response, value=Salary no disclosure on file for Bradford Wood; no disclosure on file for Sheng Xu

Stationary Computed Tomography for Space and other Resource-constrained Environments

Computed tomography (CT) is used to diagnose many emergent medical conditions, including stroke and traumatic brain injuries. Unfortunately, the size, weight, and expense of CT systems make them largely inaccessible for patients outside of major hospitals. We have designed a module containing multiple miniature x-ray sources that could allow for CT systems to be significantly lighter, smaller, and cheaper, and to operate without any moving parts. We have developed a novel photocathode-based x-ray source, created by depositing a thin film of magnesium on an electron multiplier. When illuminated by a UV LED, this photocathode emits a beam of electrons, with a beam current of up to 1 mA. The produced electrons are accelerated through a high voltage to a tungsten target. These sources are individually addressable and can be pulsed rapidly, through electronic control of the LEDs. Seven of these sources are housed together in a 17.5 degree arc within a custom vacuum manifold. A full ring of these modules could be used for CT imaging. By pulsing the sources in series, we are able to demonstrate x-ray tomosynthesis without any moving parts. With a clinical flat-panel detector, we demonstrate 3D acquisition and reconstructions of a cadaver swine lung.

Magnetic Resonance Imaging for Quantitative Assessment of Lung Aeration: A Pilot Translational Study.

Background: Computed tomography is the gold standard for lung aeration assessment, but exposure to ionizing radiation limits its application. We assessed the ability of magnetic resonance imaging (MRI) to detect changes in lung aeration in ex vivo isolated swine lung and the potential of translation of the findings to human MRI scans.Methods: We performed MRI scans in 11 isolated non-injured and injured swine lungs, as well as 6 patients both pre- and post-operatively. Images were obtained using a 1.5 T MRI scanner, with T1 – weighted volumetric interpolated breath-hold examination (VIBE) and T2 – weighted half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences. We scanned swine lungs, with reference samples of water and muscle, at different airway pressure levels: 0, 40, 10, 2 cmH2O. We investigated the relations between MRI signal intensity and both lung density and gas content fraction. We analyzed patients’ images according to the findings of the ex vivo model.Results: In the ex vivo samples, the lung T1 – VIBE signal intensity normalized to water or muscle reference signal correlated with lung density (r2 = 0.98). Thresholds for poorly and non-aerated lung tissue, expressed as MRI intensity attenuation factor compared to the deflated lung, were estimated as 0.70 [95% CI: 0.65–0.74] and 0.28 [95% CI: 0.27–0.30], respectively. In patients, dorsal versus ventral regions had a higher MRI signal intensity both pre- and post-operatively (p = 0.031). Comparing post- versus pre-operative scans, lung volume decreased (p = 0.028), while the following increased: MRI signal intensity in ventral (p = 0.043) and dorsal (p < 0.0001) regions, and percentages of non-aerated (p = 0.028) and poorly aerated tissue volumes (p = 0.028).Conclusion: Magnetic resonance imaging signal intensity is a function of lung density, decreasing linearly with increasing gas content. Lung MRI might be useful for estimating lung aeration. Compared to CT, this technique is radiation-free but requires a longer acquisition time and has a lower spatial resolution.

Pig lung transplant survival model.

Although lung transplant is a life-saving therapy for some patients, primary graft dysfunction (PGD) is a leading cause of mortality and morbidity soon after a transplant. Ischemia reperfusion injury is known to be one of the most critical factors in PGD development. PGD is by definition an acute lung injury syndrome that occurs during the first 3 d following lung transplantation. To successfully translate laboratory discoveries to clinical practice, a reliable and practical large animal model is critical. This protocol describes a surgical technique for swine lung transplantation and postoperative management for a further 3 d post transplant. The protocol includes the background and rationale, required supplies, and a detailed description of the donor operation, transplant surgery, postoperative care, and sacrifice surgery. A pig lung transplant model is reliably produced in which the recipients survive for 3 d post transplant. This 3-d survival model can be used by lung transplant researchers to assess the development of PGD and to test therapeutic strategies targeting PGD. In total, the protocol requires 5 h for the surgeries, plus ~2 h in total for the postoperative care.

Bronchoscopically Delivered Thermal Vapor Ablation of Human Lung Lesions

Background:The discovery that early diagnosis can reduce the mortality of lung cancer provides firm evidence that early surgical intervention is effective. However, surgical resection is available only to those who are healthy enough to tolerate the procedure. Vapor ablation may provide an additional method of treating the lung cancer patient, and has been studied in humans for emphysema treatment. In swine, we previously demonstrated that bronchoscopically delivered thermal vapor ablation (BTVA) could be accurately applied, was uniform, anatomically confined, and was tolerated by the animal. To provide evidence that BTVA may be a feasible method of treatment in humans, and since human and swine lungs have differing airway and segmental anatomy, we extended our studies to deceased human lungs to determine if anatomically confined and uniform ablations could be obtained with levels of energy comparable with our swine and human emphysema studies.Methods:We obtained fresh, deceased human lungs and performed BTVA with increasing energy in subsegmental regions of lung containing tumors as well as non–tumor-containing areas in order to determine if uniform ablations with sharp boundaries could be obtained in human lung.Results:We found that all ablations were anatomically contained. The frequency of uniform ablation effect was dependent on the total energy delivered and was achieved at a greater frequency than those with sharp boundaries. If a lung tumor was contained within the anatomy of the subsegment, the ablation zone completely surrounded the tumor.Conclusion:We conclude that BTVA may have a future role in the treatment of lung cancer and should be investigated further in clinical trials.