41 research outputs found
Oxygenated machine perfusion at room temperature as an alternative for static cold storage in porcine donor hearts
Background There is a continued interest in ex situ heart perfusion as an alternative strategy for donor heart preservation. We hypothesize that oxygenated machine perfusion of donor hearts at a temperature that avoids both normothermia and deep hypothermia offers adequate and safe preservation. Methods Cardioplegia-arrested porcine donor hearts were randomly assigned to six hours of preservation using cold storage (CS, n = 5) or machine perfusion using an oxygenated acellular perfusate at 21 degrees C (MP, n = 5). Subsequently, all grafts were evaluated using the Langendorff method for 120 min. Metabolic parameters and histology were analyzed. Systolic function was assessed by contractility and elastance. Diastolic function was assessed by lusitropy and stiffness. Results For both groups, in vivo baseline and post-Langendorff biopsies were comparable, as were lactate difference and myocardial oxygen consumption. Injury markers gradually increased and were comparable. Significant weight gain was seen in MP (p = 0.008). Diastolic function was not impaired in MP, and lusitropy was superior from 30 min up to 90 min of reperfusion. Contractility was superior in MP during the first hour of evaluation. Conclusion We conclude that the initial functional outcome of MP-preserved hearts was transiently superior compared to CS, with no histological injury post-Langendorff. Our machine perfusion strategy could offer feasible and safe storage of hearts prior to transplantation. Future studies are warranted for further optimization
The pleural mesothelium and TGF-β1 pathways in restrictive allograft syndrome : a pre-clinical investigation
BACKGROUND: Chronic lung allograft dysfunction (CLAD) hampers long-term survival after lung transplantation. Common fibrosis-related mechanisms in idiopathic pulmonary fibrosis and CLAD instigated the consideration of investigating the differential regulation of pleural mesothelium and transforming growth factor-beta(1) (TGF-beta(1)) in restrictive allograft syndrome (RAS).
METHODS: TGF-beta(1) was assessed in bronchoalveolar lavage (BAL) fluid using enzyme-linked immunoassay and via immune staining of explant biopsies. To assess the role of the pleura, explanted bronchiolitis obliterans syndrome (BOS) and RAS lungs were compared using computed tomography scans, calretinin stainings, Western blot, and quantititative real-time PCR. Last, a pleural mesothelial cell line was used to assess mesothelial-to-mesenchymal transition and its inhibition.
RESULTS: TGF-beta(1) was increased in BAL of RAS patients (p = 0.035), and was present in the (sub) pleural area of biopsies. Explanted RAS lungs demonstrated an increased volume fraction of pleura (p = 0.0004), a higher proportion of calretinin-positive stainings (p = 0.0032), and decreased E-cadherin (p = 0.019) and increased alpha-smooth muscle actin (p = 0.0089) mRNA expression and protein levels in isolated pleural tissue. Moreover, TGF-beta(1) stimulation of pleural mesothelial cells led to a phenotypical switch to mesenchymal cells, accompanied with an increased migratory capacity. Interleukin-1 alpha was able to accentuate TGF-beta(1). induced mesothelial-to-mesenchymal transition. None of the tested drugs could inhibit mesothelial-to-mesenchymal transition at the used concentrations.
CONCLUSIONS: Our results support an interplay between TGF-beta(1) and the pleural mesothelium in the pathophysiology of RAS. (C) 2019 International Society for Heart and Lung Transplantation. All rights reserved
Oxygenated machine perfusion at room temperature as an alternative for static cold storage in porcine donor hearts
Background There is a continued interest in ex situ heart perfusion as an alternative strategy for donor heart preservation. We hypothesize that oxygenated machine perfusion of donor hearts at a temperature that avoids both normothermia and deep hypothermia offers adequate and safe preservation. Methods Cardioplegia-arrested porcine donor hearts were randomly assigned to six hours of preservation using cold storage (CS, n = 5) or machine perfusion using an oxygenated acellular perfusate at 21 degrees C (MP, n = 5). Subsequently, all grafts were evaluated using the Langendorff method for 120 min. Metabolic parameters and histology were analyzed. Systolic function was assessed by contractility and elastance. Diastolic function was assessed by lusitropy and stiffness. Results For both groups, in vivo baseline and post-Langendorff biopsies were comparable, as were lactate difference and myocardial oxygen consumption. Injury markers gradually increased and were comparable. Significant weight gain was seen in MP (p = 0.008). Diastolic function was not impaired in MP, and lusitropy was superior from 30 min up to 90 min of reperfusion. Contractility was superior in MP during the first hour of evaluation. Conclusion We conclude that the initial functional outcome of MP-preserved hearts was transiently superior compared to CS, with no histological injury post-Langendorff. Our machine perfusion strategy could offer feasible and safe storage of hearts prior to transplantation. Future studies are warranted for further optimization.</p
The prognostic value of the hypoxia markers CA IX and GLUT 1 and the cytokines VEGF and IL 6 in head and neck squamous cell carcinoma treated by radiotherapy ± chemotherapy
BACKGROUND: Several parameters of the tumor microenvironment, such as hypoxia, inflammation and angiogenesis, play a critical role in tumor aggressiveness and treatment response. A major question remains if these markers can be used to stratify patients to certain treatment protocols. The purpose of this study was to investigate the inter-relationship and the prognostic significance of several biological and clinicopathological parameters in patients with head and neck squamous cell carcinoma (HNSCC) treated by radiotherapy ± chemotherapy. METHODS: We used two subgroups of a retrospective series for which CT-determined tumoral perfusion correlated with local control. In the first subgroup (n = 67), immunohistochemistry for carbonic anhydrase IX (CA IX) and glucose transporter-1 (GLUT-1) was performed on the pretreatment tumor biopsy. In the second subgroup (n = 34), enzyme linked immunosorbent assay (ELISA) was used to determine pretreatment levels of the cytokines vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in serum. Correlation was investigated between tumoral perfusion and each of these biological markers, as well as between the markers mutually. The prognostic value of these microenvironmental parameters was also evaluated. RESULTS: For CA IX and GLUT-1, the combined assessment of patients with both markers expressed above the median showed an independent correlation with local control (p = 0.02) and disease-free survival (p = 0.04) with a trend for regional control (p = 0.06). In the second subgroup, IL-6 pretreatment serum level above the median was the only independent predictor of local control (p = 0.009), disease-free survival (p = 0.02) and overall survival (p = 0.005). CONCLUSION: To our knowledge, we are the first to report a link in HNSCC between IL-6 pretreatment serum levels and radioresistance in vivo. This link is supported by the strong prognostic association of pretreatment IL-6 with local control, known to be the most important parameter to judge radiotherapy responses. Furthermore, the combined assessment of CA IX and GLUT-1 correlated independently with prognosis. This is a valuable indication that a combined approach is important in the investigation of prognostic markers
The inner and outer of our thorax: silicone breast implants and pulmonary alveolar proteinosis
Pulmonary alveolar (phospholipo)proteinosis (PAP) is a rare lung disease, predominantly autoimmune in nature. This case report describes a patient with insidious dyspnoea since 5 years and a milky appearance of her bronchoalveolar fluid, leading to the diagnosis of PAP. The onset of symptoms coincided with an exchange of her silicone breast implants. Giant cell reaction in axillary adenopathies pointed towards silicone leakage. Adjuvants, such as silicone, might boost pre-existing antigen reactions of the immune system, potentially leading to autoimmune phenomena.peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope.
aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=yacb20status: publishe
Role of F-18-FDG PET/CT in Restrictive Allograft Syndrome After Lung Transplantation
BACKGROUND: Differential diagnosis of phenotypes of chronic lung allograft dysfunction (CLAD) remains troublesome. We hypothesized that F-fluorodeoxyglucose positron emission tomography with computed tomography (F-FDG PET/CT) may help in differential diagnosis of CLAD phenotypes, as it showed promising results regarding diagnosis and prognosis in interstitial lung diseases. METHODS: A monocentric, retrospective study was performed including all lung transplant recipients suffering from bronchiolitis obliterans syndrome (BOS) or restrictive allograft syndrome (RAS) who underwent F-FDG PET/CT scan, in comparison with stable lung transplant recipients. Maximum standardized uptake value (SUVmax) was associated with pulmonary function and survival. Proof-of-concept microCT and glucose transporter-1 staining served as morphologic validation for regions with different SUVmax. RESULTS: Maximum standardized uptake value was higher in RAS (median, 2.6; n = 29) compared with BOS (median, 1.0; n = 15) and stable patients (median, 0.59; n = 8) (P < 0.0001). In RAS, high SUVmax was associated with worse survival after F-FDG PET/CT (P = 0.0004; hazard ratio, 1.82). Forced vital capacity at F-FDG PET/CT inversely correlated with SUVmax (R = -0.40, P = 0.03). MicroCT analysis revealed extensive fibrosis in regions of high SUVmax, with an increased number of glucose transporter-1-positive cells. CONCLUSIONS: F-fluorodeoxyglucose positron emission tomography with CT may noninvasively differentiate RAS from BOS. RAS patients with areas of increased lung metabolism have worse outcome, demonstrating the potential use of F-FDG PET/CT during follow-up after lung transplantation.status: publishe
Morphologic changes and methodological issues in the rabbit experimental model for diaphragmatic hernia
Summary. Fetal lung development may be impaired by
some congenital anomalies or in utero events. Animal
models are used to understand the pathophysiology of
these diseases and explore therapeutic strategies. Our
group has an interest in the prenatal management of
congenital diaphragmatic hernia (CDH). Isolated CDH
remains associated with a 30% mortality because of lung
hypoplasia and pulmonary hypertension.
On day 23 of gestation (pseudoglandular stage)
CDH was created in both ovarian-end fetuses (n=28) in
14 time-mated pregnant white rabbits (hybrid of
Dendermonde and New-Zealand White). At term (day
30) all survived operated fetuses and size-matched
controls were harvested. Fetuses/lungs were assigned
randomly to formalin fixation either under pressure of 25
cm H2O (CDH25 n=5; CTR25 n=5) or without (0 cm
H2O (CDH0 n=7; CTR0 n=7). Fetuses and lungs were
first weighed, and then the lungs were processed for
morphometry. Pulmonary development was evaluated by
lung-to-body weight ratio (LBWR) and airway and
vascular morphometry.
Surgical induction of CDH does reduce the LBWR
to hypoplastic levels. The contralateral lung weight is
81% of what is expected, whereas the ipsilateral lung is
only 46% of the normal. This was accompagnied by a
loss of conducting airway generations, precisely,
terminal bronchioles (TB), which were surrounded by
less alveoli. The ipsilateral CDH lung demonstrated a
thickened media in the peripheral arteries as well. As a
result, in the severely hypoplastic ipsilateral lung, an
airway fixation pressure of 25 H2O has no significant
effect on the morphometric indices. The contralateral
lung has a normal amount of alveoli around a single TB,
which also behave like alveoli of the normal lung, i.e.
expand under pressure fixation.
The present study on severely hypoplastic lungs that
never respirated, shows that in contrast to normal lungs,
the morphometric indices are not significantly
influenced by a difference in fixation pressure.
Increasing fixation pressure seems to expand the lung
only when sufficient alveolated parenchyma is present
The pleural mesothelium and transforming growth factor-beta(1) pathways in restrictive allograft syndrome: A pre-clinical investigation
BACKGROUND: Chronic lung allograft dysfunction (CLAD) hampers long-term survival after lung transplantation. Common fibrosis-related mechanisms in idiopathic pulmonary fibrosis and CLAD instigated the consideration of investigating the differential regulation of pleural mesothelium and transforming growth factor-β1 (TGF-β1) in restrictive allograft syndrome (RAS). METHODS: TGF-β1 was assessed in bronchoalveolar lavage (BAL) fluid using enzyme-linked immunoassay and via immune staining of explant biopsies. To assess the role of the pleura, explanted bronchiolitis obliterans syndrome (BOS) and RAS lungs were compared using computed tomography scans, calretinin stainings, Western blot, and quantititative real-time PCR. Last, a pleural mesothelial cell line was used to assess mesothelial-to-mesenchymal transition and its inhibition. RESULTS: TGF-β1 was increased in BAL of RAS patients (p = 0.035), and was present in the (sub)pleural area of biopsies. Explanted RAS lungs demonstrated an increased volume fraction of pleura (p = 0.0004), a higher proportion of calretinin-positive stainings (p = 0.0032), and decreased E-cadherin (p = 0.019) and increased α-smooth muscle actin (p = 0.0089) mRNA expression and protein levels in isolated pleural tissue. Moreover, TGF-β1 stimulation of pleural mesothelial cells led to a phenotypical switch to mesenchymal cells, accompanied with an increased migratory capacity. Interleukin-1α was able to accentuate TGF-β1‒induced mesothelial-to-mesenchymal transition. None of the tested drugs could inhibit mesothelial-to-mesenchymal transition at the used concentrations. CONCLUSIONS: Our results support an interplay between TGF-β1 and the pleural mesothelium in the pathophysiology of RAS.status: publishe
Diffusion-Weighted Magnetic Resonance Imaging Allows Noninvasive In Vivo Monitoring of the Effects of Combretastatin A-4 Phosphate after Repeated Administration
The noninvasive assessment of anticancer treatment efficacy is very important for the improvement of therapeutic window. The purpose of the present study was to evaluate the antitumoral effects of the vascular targeting agent, combretastatin A-4 phosphate (CA-4-P), at selected time points after repeated intraperitoneal drug administrations (25 mg/kg), using diffusion-weighted magnetic resonance imaging (DW-MRI). The experiments were performed during an overall follow-up period of 3 weeks on WAG/Rij rats with subcutaneously growing rhabdomyosarcomas. Each animal served as its own baseline. The DW-MRI studies were quantified by calculating the apparent diffusion coefficient (ADC) for different low and high b-values to separate the effects on tumor vasculature and cellular integrity. The changes in ADC as well as the extent of necrosis development (proportional to the tumor volume), measured on the MR images, were of comparable magnitude after each treatment. All ADC values showed a significant decrease at 6 hours, followed by a significant increase at 2 days for various CA-4-P administrations. DW-MRI allowed us to monitor both reduction in perfusion and changes in the extent of tumor necrosis after CA-4-P injection. Repeated CA-4-P administration retains efficacy in rat rhabdomyosarcomas, with similar findings after each drug administration