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Chronic injury of alveolar epithelial type II cells (AE2 cells) represents a key event in the development of lung fibrosis in animal models and in humans, such as idiopathic pulmonary fibrosis (IPF). Intratracheal delivery of amiodarone to mice results in a profound injury and macroautophagydependent apoptosis of AE2 cells. Increased autophagy manifested in AE2 cells by disturbances of the intracellular surfactant. Hence, we hypothesized that ultrastructural alterations of the intracellular surfactant pool are signs of epithelial stress correlating with the severity of fibrotic remodeling. With the use of design-based stereology, the amiodarone model of pulmonary fibrosis in mice was characterized at the light and ultrastructural level during progression. Mean volume of AE2 cells, volume of lamellar bodies per AE2 cell, and mean size of lamellar bodies were correlated to structural parameters reflecting severity of fibrosis like collagen content. Within 2 wk amiodarone leads to an increase in septal wall thickness and a decrease in alveolar numbers due to irreversible alveolar collapse associated with alveolar surfactant dysfunction. Progressive hypertrophy of AE2 cells and increase in mean individual size and total volume of lamellar bodies per AE2 cell were observed. A high positive correlation of these AE2 cell-related ultrastructural changes and the deposition of collagen fibrils within septal walls were established. Qualitatively, similar alterations could be found in IPF samples with mild to moderate fibrosis. We conclude that ultrastructural alterations of AE2 cells including the surfactant system are tightly correlated with the progression of fibrotic remodeling. [ABSTRACT FROM AUTHOR]

Fibroblast growth factors (Fgfs) mediate organ repair. Lung epithelial cell overexpression of Fgf10 postbleomycin injury is both protective and therapeutic, characterized by increased survival and attenuated fibrosis. Exogenous administration of FGF7 (palifermin) also showed prophylactic survival benefits in mice. The role of endogenous Fgfr2b ligands on bleomycin-induced lung fibrosis is still elusive. This study reports the expression of endogenous Fgfr2b ligands, receptors, and signaling targets in wildtype mice following bleomycin lung injury. In addition, the impact of attenuating endogenous Fgfr2b-ligands following bleomycin-induced fibrosis was tested by using a doxycycline (dox)-based inducible, soluble, dominant-negative form of the Fgfr2b receptor. Doubletransgenic (DTG) Rosa26rtTA/+;tet(O)solFgfr2b mice were validated for the expression and activity of soluble Fgfr2b (failure to regenerate maxillary incisors, attenuated recombinant FGF7 signal in the lung). As previously reported, no defects in lung morphometry were detected in DTG (dox) mice exposed from postnatal days (PN) 1 through PN105. Female single-transgenic (STG) and DTG mice were subjected to various levels of bleomycin injury (1.0, 2.0, and 3.0 U/kg). Fgfr2b ligands were attenuated either throughout injury (days 0-11; days 0-28) or during later stages (days 6-28 and 14-28). No significant changes in survival, weight, lung function, confluent areas of fibrosis, or hydroxyproline deposition were detected in DTG mice. These results indicate that endogenous Fgfr2b ligands do not significantly protect against bleomycin injury, nor do they expedite the resolution of bleomycin-induced lung injury in mice. [ABSTRACT FROM AUTHOR]

Background: Recent clinical studies show that tyrosine kinase inhibitors slow the rate of lung function decline and decrease the number of acute exacerbations in patients with Idiopathic Pulmonary Fibrosis (IPF). However, in the murine bleomycin model of fibrosis, not all tyrosine kinase signaling is detrimental. Exogenous ligands Fibroblast Growth Factor (FGF) 7 and 10 improve murine lung repair and increase survival after injury via tyrosine kinase FGF receptor 2b-signaling. Therefore, the level and location of FGF/FGFR expression as well as the exogenous effect of the most highly expressed FGFR2b ligand, FGF1, was analyzed on human lung fibroblasts. Methods: FGF ligand and receptor expression was evaluated in donor and IPF whole lung homogenates using western blotting and qPCR. Immunohistochemistry for FGF1 and FGFR1/2/3/4 were performed on human lung tissue. Lastly, the effects of FGF1, a potent, multi-FGFR ligand, were studied on primary cultures of IPF and non-IPF donor fibroblasts. Western blots for pro-fibrotic markers, proliferation, FACS for apoptosis, transwell assays and MetaMorph analyses on cell cultures were performed. Results: Whole lung homogenate analyses revealed decreased FGFR b-isoform expression, and an increase in FGFR c-isoform expression. Of the FGFR2b-ligands, FGF1 was the most significantly increased in IPF patients; downstream targets of FGF-signaling, p-ERK1/2 and p-AKT were also increased. Immunohistochemistry revealed FGF1 co-localization within basal cell sheets, myofibroblast foci, and Surfactant protein-C positive alveolar epithelial type-II cells as well as co-localization with FGFR1, FGFR2, FGFR3, FGFR4 and myofibroblasts expressing the migratory marker Fascin. Both alone and in the presence of heparin, FGF1 led to increased MAPK-signaling in primary lung fibroblasts. While smooth muscle actin was unchanged, heparin + FGF1 decreased collagen production in IPF fibroblasts. In addition, FGF1 + heparin increased apoptosis and cell migration. The FGFR inhibitor (PD173074) attenuated these effects. Conclusions: Strong expression of FGF1/FGFRs in pathogenic regions of IPF suggest that aberrant FGF1-FGFR signaling is increased in IPF patients and may contribute to the pathogenesis of lung fibrosis by supporting fibroblast migration and increased MAPK-signaling. [ABSTRACT FROM AUTHOR]

Summary Background Panobinostat is a potent oral pan-deacetylase inhibitor that in preclinical studies has synergistic anti-myeloma activity when combined with bortezomib and dexamethasone. We aimed to compare panobinostat, bortezomib, and dexamethasone with placebo, bortezomib, and dexamethasone in patients with relapsed or relapsed and refractory multiple myeloma. Methods PANORAMA1 is a multicentre, randomised, placebo-controlled, double-blind phase 3 trial of patients with relapsed or relapsed and refractory multiple myeloma who have received between one and three previous treatment regimens. Patients were randomly assigned (1:1) via an interactive web-based and voice response system, stratified by number of previous treatment lines and by previous use of bortezomib, to receive 21 day cycles of placebo or panobinostat (20 mg; on days 1, 3, 5, 8, 10, 12, orally), both in combination with bortezomib (1·3 mg/m 2 on days 1, 4, 8, 11, intravenously) and dexamethasone (20 mg on days 1, 2, 4, 5, 8, 9, 11, 12, orally). Patients, physicians, and the investigators who did the data analysis were masked to treatment allocation; crossover was not permitted. The primary endpoint was progression-free survival (in accordance with modified European Group for Blood and Marrow Transplantation criteria and based on investigators' assessment) and was analysed by intention to treat. The study is ongoing, but no longer recruiting, and is registered at ClinicalTrials.gov , number NCT01023308 . Findings 768 patients were enrolled between Jan 21, 2010, and Feb 29, 2012, with 387 randomly assigned to panobinostat, bortezomib, and dexamethasone and 381 to placebo, bortezomib, and dexamethasone. Median follow-up was 6·47 months (IQR 1·81–13·47) in the panobinostat group and 5·59 months (2·14–11·30) in the placebo group. Median progression-free survival was significantly longer in the panobinostat group than in the placebo group (11·99 months [95% CI 10·33–12·94] vs 8·08 months [7·56–9·23]; hazard ratio [HR] 0·63, 95% CI 0·52–0·76; p<0·0001). Overall survival data are not yet mature, although at the time of this analysis, median overall survival was 33·64 months (95% CI 31·34–not estimable) for the panobinostat group and 30·39 months (26·87–not estimable) for the placebo group (HR 0·87, 95% CI 0·69–1·10; p=0·26). The proportion of patients achieving an overall response did not differ between treatment groups (235 [60·7%, 95% CI 55·7–65·6] for panobinostat vs 208 [54·6%, 49·4–59·7] for placebo; p=0·09); however, the proportion of patients with a complete or near complete response was significantly higher in the panobinostat group than in the placebo group (107 [27·6%, 95% CI 23·2–32·4] vs 60 [15·7%, 12·2–19·8]; p=0·00006). Minimal responses were noted in 23 (6%) patients in the panobinostat group and in 42 (11%) in the placebo group. Median duration of response (partial response or better) was 13·14 months (95% CI 11·76–14·92) in the panobinostat group and 10·87 months (9·23–11·76) in the placebo group, and median time to response (partial response or better) was 1·51 months (1·41–1·64) in the panobinostat group and 2·00 months (1·61–2·79) in the placebo group. Serious adverse events were reported in 228 (60%) of 381 patients in the panobinostat group and 157 (42%) of 377 patients in the placebo group. Common grade 3–4 laboratory abnormalities and adverse events (irrespective of association with study drug) included thrombocytopenia (256 [67%] in the panobinostat group vs 118 [31%] in the placebo group), lymphopenia (202 [53%] vs 150 [40%]), diarrhoea (97 [26%] vs 30 [8%]), asthenia or fatigue (9 [ABSTRACT FROM AUTHOR]

Posttranslational modification of the neural cell adhesion molecule (NCAM) by polysialic acid (polySia) is well studied in the nervous system and described as a dynamic modulator of plastic processes like precursor cell migration, axon fasciculation, and synaptic plasticity. Here, we describe a novel function of polysialylated NCAM (polySia-NCAM) in innate immunity of the lung. In mature lung tissue of healthy donors, polySia was exclusively attached to the transmembrane isoform NCAM-140 and located to intracellular compartments of epithelial cells. In patients with chronic obstructive pulmonary disease, however, increased polySia levels and processing of the NCAM carrier were observed. Processing of polysialylated NCAM was reproduced in a mouse model by bleomycin administration leading to an activation of the inflammasome and secretion of interleukin (IL)-1β. As shown in a cell culture model, polySia-NCAM-140 was kept in the late trans-Golgi apparatus of lung epithelial cells and stimulation by IL-1β or lipopolysaccharide induced metalloprotease-mediated ectodomain shedding, resulting in the secretion of soluble polySia-NCAM. Interestingly, polySia chains of secreted NCAM neutralized the cytotoxic activity of extracellular histones as well as DNA/histone-network-containing 'neutrophil extracellular traps', which are formed during invasion of microorganisms. Thus, shedding of polySia-NCAM by lung epithelial cells may provide a host-protective mechanism to reduce tissue damage during inflammatory processes. [ABSTRACT FROM AUTHOR]

Background: In patients failing successful conventional mobilization of hematopoietic progenitor cells (HPC) plerixafor (Mozobil®) seems to be an alternative. We report a series of 14 patients with multiple myeloma or NHL successfully mobilized and harvested by plerixafor together with large-volume leukaphereses (LVL). Methods: In a first series (GI), 5 patients were mobilized with G-CSF and plerixafor. In the second series (GII), 9 patients were mobilized by chemotherapy, G-CSF, and plerixafor. Results: In GI and GII, addition of plerixafor led to a significant (p < 0.01) increase of leukocytes and CD34+ cells in peripheral blood (PB). In GII, the median number of CD34+ cells in PB before and after addition of plerixafor was significantly (p = 0.019) higher compared to GI (9 vs. 5 and 50 vs. 24 cells/µl, respectively). In GI and GII, a median number of three or one aphereses was performed. In GII, the median yield (6.7 × 106 CD34+ cells/kg) of the first apheresis and the median intra-apheresis recruitment of CD34+ cells were significantly (p < 0.05) higher compared to GI (2.94 × 106 CD34+ cells/kg). All patients transplanted, 5 in GI and 8 in GII, exhibited successful engraftment. Conclusions: Plerixafor and G-CSF mobilization or the addition of plerixafor during non-optimal chemotherapy and G-CSF mobilization together with LVL enabled, independent of leukocyte count and even without detectable CD34+ cells before addition of plerixafor, sufficient harvest of HPC numbers for transplantation. Addition of plerixafor during chemotherapy and G-CSF mobilization led to an increased intra-apheresis recruitment and a significantly higher yield of CD34+ cells compared to plerixafor and G-CSF steady-state mobilized patients. © 2013 S. Karger GmbH, Freiburg [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluated the use of a new dry powder aerosolizer for administration of a recombinant surfactant protein-C-based surfactant in animal models of acute lung injury. The setting of the laboratory experiment was at a university laboratory and involved rabbits and mice. The researchers concluded that dry powder aerosolizer has the potential to be an effective therapy of acute lung injury/acute respiratory distress syndrome.

The article presents a study on the search for subgroups of Adult Respiratory Distress Syndrome (ARDS) patients who can benefit from recombinant surfactant protein-surfactant (rSP-C) surfactant therapy. A pooled analysis of five multicenter studies of ARDS patients treated with rSP-C surfactant was made and factors were observed using logistic regression analysis and multivariate analysis. Results show that rSP-C surfactant treatment ameliorated oxygenation but had no effect on mortality.

Upon vascular injury, locally controlled haemostasis prevents life-threatening blood loss and ensures wound healing. Intracellular material derived from damaged cells at these sites will become exposed to blood components and could contribute to blood coagulation and pathological thrombus formation. So far, the functional and mechanistic consequences of this concept are not understood. Here, we present in vivo and in vitro evidence that different forms of eukaryotic and prokaryotic RNA serve as promoters of blood coagulation. Extracellular RNA was found to augment (auto-)activation of proteases of the contact phase pathway of blood coagulation such as factors XII and XI, both exhibiting strong RNA binding. Moreover, administration of exogenous RNA provoked a significant procoagulant response in rabbits. In mice that underwent an arterial thrombosis model, extracellular RNA was found associated with fibrin-rich thrombi, and pretreatment with RNase (but not DNase) significantly delayed occlusive thrombus formation. Thus, extracellular RNA derived from damaged or necrotic cells particularly under pathological conditions or severe tissue damage represents the long sought natural ‘foreign surface’ and provides a procoagulant cofactor template for the factors XII/XI-induced contact activation/amplification of blood coagulation. Extracellular RNA thereby reveals a yet unrecognized target for antithrombotic intervention, using RNase or related therapeutic strategies. [ABSTRACT FROM AUTHOR]

Abstract: Conversion of the biophysically active large surfactant aggregate subtype of alveolar surfactant into the less surface active small surfactant aggregates occurs in vitro and in vivo, possibly in dependency of a carboxylesterase, entitled surfactant convertase. The substrate has yet not been safely identified. Utilizing the in vitro cycling assay we investigated conversion of an organic rabbit lavage extract reconstituted with SP-A. Porcine liver carboxylesterase, which is closely related to surfactant convertase, induced subtype conversion to a similar degree as compared with native lavage fluid containing endogenous convertase. In addition, we asked for cleavage products of SP-B and identified a ∼12kDa band upon cycling with liver carboxylesterase, having the same N-terminus as mature SP-B. A band of same molecular weight was found in native lavage fluid after in vitro conversion mediated by the endogenous convertase. We conclude that SP-B plays a pivotal role during subtype conversion and represents the substrate for surfactant convertase. [Copyright &y& Elsevier]

Objective: Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and is characterized by severe impairment of pulmonary gas exchange, surfactant inactivation, and pronounced inflammatory changes. Surfactant administration has been shown as an effective treatment strategy in MAS. The present study aimed at investigating the impact of a recombinant surfactant protein (SP)-C-based surfactant on pulmonary gas exchange and lung function in this model of neonatal lung injury. Furthermore, SP-B and -C were determined on the transcriptional and protein level.Design: Laboratory experiment.Setting: University laboratory.Subjects: Twenty three newborn piglets (median age 6 days, weight 1900-2500 g).Interventions: Piglets were intubated and mechanically ventilated and then received 20% sterile meconium (5 mL/kg) for induction of lung injury. After 30 mins, animals were randomized for control (n = 7, MAS controls), recombinant SP-C surfactant (n = 8), or natural surfactant (n = 8). Surfactant preparations were administered as an intratracheal bolus (75 mg/kg), and animals were ventilated for another 330 mins. Nonventilated newborn piglets at term (n = 28; median weight 1484 g, range 720-1990 g) served as a healthy reference group (healthy controls).Measurements and Main Results: Lung function variables, arterial blood gas samples, and lung tissues were obtained. Expression of SP-B and -C messenger RNA was quantified in left lung lobe tissue using real-time polymerase chain reaction. Protein concentrations were determined by enzyme-linked immunosorbent assay. Scanning electron microscopy and transmission electron microscopy were performed in tissue samples of the right lung lobe. Compared with healthy controls, SP-B messenger RNA expression was significantly increased in MAS (p < .02), whereas SP-C messenger RNA expression was found to be significantly reduced (p < .001). SP concentrations, however, were not significantly different. Although a significant improvement of gas exchange and lung function was observed after surfactant administration in both groups, surfactant messenger RNA expression and protein concentrations were not significantly altered. Scanning and transmission electron microscopy showed severe pulmonary ultrastructural changes after meconium aspiration improving after surfactant treatment.Conclusions: Impairment of lung function in MAS, associated with marked changes in SP messenger RNA expression, can be sufficiently treated using recombinant SP-C-based or natural surfactant. Despite improved lung function and gas exchange as well as pulmonary ultrastructure after treatment, pulmonary SP messenger RNA expression and concentrations remained significantly affected, giving important insight into the time course following surfactant treatment in MAS. [ABSTRACT FROM AUTHOR]

Background: Pulmonary ischemia/reperfusion injury represents a common clinical phenomenon after lung transplantation, pulmonary embolism, and cardiac surgery with extracorporeal circulation. We investigated the influence of ischemic and endotoxin pre-conditioning on gas exchange and surfactant properties in a canine model of ischemia/reperfusion injury. Methods: Twenty-six foxhounds underwent 3 hours of warm ischemia of the left lung, followed by 8 hours of reperfusion. Ischemic pre-conditioning was performed for either 5 minutes (IPC-5) or by 2 10-minute ischemic periods (IPC-10), before ischemia. For endotoxin pre-conditioning, dogs were pre-treated by a daily intravenous application of increasing amounts of endotoxin for 6 days. No pre-conditioning was performed in the controls. Bronchoalveolar lavage was performed before ischemia/reperfusion injury (baseline) and after the 8-hour reperfusion period in the non-injured right and in the reperfused left lung. Bronchoalveolar lavage fluids were analyzed for the phospholipid-protein ratio, the content of large surfactant aggregates, the phospholipid and neutral lipid profile, the surfactant protein (SP) content, and for biophysical activity. Results: Severe surfactant alterations were observed in the ischemia/reperfusion-injured left lung, with increased protein concentrations and depressed concentrations of large surface aggregates, SP-B, dipalmitoylated phosphatidylcholine, and phosphatidylglycerol. Endotoxin pre-conditioning and IPC-5 were both capable of greatly preventing the ischemia/reperfusion injury-related deterioration of surfactant properties. IPC-10 exerted no effects. Endotoxin pre-conditioning and IPC-5, but not IPC-10, also prevented loss of gas exchange. Conclusions: Ischemic and endotoxin pre-conditioning may protect against impairment of gas exchange in ischemia/reperfusion injury by restoring physiological surfactant properties. [Copyright &y& Elsevier]

Noninvasive radiologic imaging has recently gained considerable interest in basic and preclinical research for monitoring disease progression and therapeutic efficacy. In this report, we introduce flat-panel volumetric computed tomography (fpVCT) as a powerful new tool for noninvasive imaging of different organ systems in preclinical research. The three-dimensional visualization that is achieved by isotropic high-resolution datasets is illustrated for the skeleton, chest, abdominal organs, and brain of mice. The high image quality of chest scans enables the visualization of small lung nodules in an orthotopic lung cancer model and the reliable imaging of therapy side effects such as lung fibrosis. Using contrast-enhanced scans, fpVCT displayed the vascular trees of the brain, liver, and kidney down to the subsegmental level. Functional application of fpVCT in dynamic contrast-enhanced scans of the rat brain delivered physiologically reliable data of perfusion and tissue blood volume. Beyond scanning of small animal models as demonstrated here, fpVCT provides the ability to image animals up to the size of primates. [ABSTRACT FROM AUTHOR]

Bleomycin is a widely accepted cancer drug but may induce life-threatening interstitial lung disease in a subset of patients. We evaluated the effect of bleomycin administration on pulmonary surfactant function and composition in rabbit lungs. In order to obtain a uniform response to bleomycin, aerosol technology was employed for bronchoalveolar delivery of 1.8 U/kg b.w. bleomycin. On days 4, 8, 16, 24, 32, and 64 after challenge, bronchoalveolar lavages were performed. Sham-aerosolized rabbits served as controls. In the early acute respiratory distress syndrome (ARDS)-like post-bleomycin period (4–16 days), marked loss of surface activity of the large surfactant aggregate (LA) fraction of surfactant was noted. In parallel, reduced percentages of LA, but only minor changes in surfactant apoproteins (SP)-A, SP-B, and SP-C, were encountered. Analysis of the surfactant lipid profile showed impressively enhanced cholesterol and significantly decreased phosphatidylglycerol (PG) levels. The relative content of dipalmitoyl-PC (DPPC) was slightly increased, and a several-fold increase within the 1-O-alkyl-2-acyl subclass of PC was observed. During the prolonged fibroproliferative period, a highly significant downregulation of SP-B and SP-C levels was observed. This was paralleled by an upregulation of the total extracellular phospholipid pool, with a far-reaching normalization of the (phospho)-lipid profile. The biophysical surfactant function never fully normalized within the 64-day observation period. In conclusion, bleomycin caused marked abnormalities of pulmonary surfactant, with the profile of changes being different between the early ARDS and the late fibrotic phase. [Copyright &y& Elsevier]

Increases in free radicals are believed to play a central role in the development of pulmonary ischemia/reperfusion (I-R) injury, leading to microvascular leakage and deterioration of pulmonary surfactant. Continued ventilation during ischemia offers significant protection against I-R injury, but the impact of alveolar oxygen supply both on lung injury and on radical generation is still unclear. We investigated the influence of hyperoxic (95% O2) and anoxic (0% O2) ventilation during ischemia on alveolar antioxidant status and surfactant properties in isolated rabbit lungs. Normoxic and hyperoxic ventilated, buffer-perfused lungs (n = 5 or 6) and native lungs (n = 6) served as controls. As compared with controls, biophysical and biochemical surfactant properties were not altered in anoxic as well as hyperoxic ventilated ischemic (2, 3, and 4 h) lungs. Assessment of several antioxidants (reduced glutathione (GSH), α-tocopherol (vitamin E), retinol (vitamin A), ascorbic acid (vitamin C), uric acid, and plasmalogens (1-O-alkenyl-2-acyl-phospholipids)) in bronchoalveolar lavage fluid (BALF) revealed a significant increase in antioxidant compounds under anoxic and hyperoxic ventilation, with maximum levels occuring after 3 h of ischemia. For example, GSH increased to 5.1 ± 0.8 μM (mean ± SE, p < .001) after 3 h of anoxic ventilated ischemia and to 2.7 ± 0.2 μM (p < .01) after hyperoxic ventilated ischemia compared with native controls (1.3 ± 0.2 μM), but did not significantly change under anoxic and hyperoxic ventilation alone. In parallel, under ischemic conditions, oxidized glutathione (GSSG) increased during hyperoxic (3 h: 0.81 ± 0.04 μM, p < .001), but remained unchanged during anoxic (3 h: 0.31 ± 0.04 μM) ventilation compared with native controls (0.22 ± 0.02 μM), whereas F2-isoprostanes were elevated under both hyperoxic (3 h: 63 ± 15 pM, p < .01) and anoxic (3 h: 50 ± 9 pM, p < .01) ventilation compared with native controls (16 ± 4 pM). We conclude that oxidative stress is increased in the lung alveolar lining layer during ischemia, during both anoxic and hyperoxic ventilation. This is paralleled by an increase rather than a decrease in alveolar antioxidant levels, suggested to reflect an adaptive response to oxidative stress during ischemia. [Copyright &y& Elsevier]

The extracellular alveolar surfactant can be separated into the highly surface active large surfactant aggregates (LA) and the less active small surfactant aggregates (SA). Conversion of LA to SA is encountered upon cyclic surface area changes and demands the presence of enzymatic activity. In the present study we investigated the influence of surface tension on the conversion of LA to SA. Bronchoalveolar lavage fluid (BALF) obtained from healthy rabbits was cycled for various time periods in absence or presence of increasing amounts of serum proteins or oleic acid. LA were isolated, quantified and the minimum surface tension (γmin) of uncycled or cycled LA was assessed in absence or presence of increasing amounts of serum proteins or oleic acid. In additional experiments, already cycled LA with a γmin of∼20 mN/m were pooled, diluted to a similar PL concentration as original BALF and cycled a second time. Serum proteins and oleic acid dose-dependently: (i) increased the γmin values of LA when added to the isolated LA; and (ii) decreased the LA to SA conversion when added to BALF. These events were directly correlated, suggesting inhibition of LA to SA conversion by increase in γmin of the LA fraction. In line with this suggestion, already cycled LA displaying poor surface activity showed no further conversion in a second cycling maneuver, whereas LA being similarly prepared from uncycled BALF did. We conclude that LA to SA conversion is inversely correlated with the surface tension of the LA fraction. An increase in γmin of the LA fraction during the cycling procedure blocks further LA to SA conversion and may thus represent a negative feedback mechanism. [Copyright &y& Elsevier]

Hypoxic pulmonary vasoconstriction (HPV) matches lung perfusion to ventilation for optimizing pulmonary gas exchange. Chronic alveolar hypoxia results in vascular remodeling and pulmonary hypertension. Previous studies have reported conflicting results of the effect of chronic alveolar hypoxia on pulmonary vasoreactivity and the contribution of nitric oxide (NO), which may be related to species and strain differences as well as to the duration of chronic hypoxia. Therefore, we investigated the impact of chronic hypoxia on HPV in rabbits, with a focus on lung NO synthesis. After exposure of the animals to normobaric hypoxia (10% O[sub 2]) for 1 day to 10 wk, vascular reactivity was investigated in ex vivo perfused normoxic ventilated lungs. Chronic hypoxia induced right heart hypertrophy and increased normnoxic vascular tone within weeks. The vasoconstrictor response to an acute hypoxic challenge was strongly downregulated within 5 days, whereas the vasoconstrictor response to the thromboxane mimetic U-46619 was maintained. The rapid downregulation of HPV was apparently not linked to changes in the lung vascular NO system, detectable in the exhaled gas and by pharmacological blockage of NO synthesis. Treatment of the animals with longterm inhaled NO reduced right heart hypertrophy and partially maintained the reactivity to acute hypoxia, without any impact on the endogenous NO system being noted. We conclude that chronic hypoxia causes rapid downregulation of acute HPV as a specific event, preceding the development of major pulmonary hypertension and being independent of the lung vascular NO system. Long-term NO inhalation partially maintains the strength of the hypoxic vasoconstrictor response. [ABSTRACT FROM AUTHOR]

We study a hitherto unexplored regime of the Rydberg excitation blockade using highly Stark-shifted, yet long-living, states of Rb atoms subject to electric fields above the classical ionization limit. Such states allow tuning the dipole-dipole interaction strength while their ionization rate can be changed over 2 orders of magnitude by small variations of the electric field. We demonstrate laser excitation of the interacting Rydberg states followed by their detection using controlled ionization and magnified imaging with high spatial and temporal resolution. Our work reveals new possibilities to engineer the interaction strength and dynamically control the ionization and detection of Rydberg atoms, which can be useful for realizing and assessing quantum simulators that vary in space and time. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) scans are the gold standard to measure treatment success of non-small cell lung cancer (NSCLC) therapies. Here, we investigated the very early tumor response of patients receiving chemotherapy or targeted therapies using a panel of already established and explorative liquid biomarkers. Blood samples from 50 patients were taken at baseline and at three early time points after therapy initiation. DNA mutations, a panel of 17 microRNAs, glycodelin, glutathione disulfide, glutathione, soluble caspase-cleaved cytokeratin 18 (M30 antigen), and soluble cytokeratin 18 (M65 antigen) were measured in serum and plasma samples. Baseline and first follow-up CT scans were evaluated and correlated with biomarker data. The detection rate of the individual biomarkers was between 56% and 100%. While only keratin 18 correlated with the tumor load at baseline, we found several individual markers correlating with the tumor response to treatment for each of the three time points of blood draws. A combination of the five best markers at each time point resulted in highly significant marker panels indicating therapeutic response (R2 = 0.78, R2 = 0.71, and R2 = 0.71). Our study demonstrates that an early measurement of biomarkers immediately after therapy start can assess tumor response to treatment and might support an adaptation of treatment to improve patients' outcome. [ABSTRACT FROM AUTHOR]

The proteasome is essential for the selective degradation of most cellular proteins and is fine-tuned according to cellular needs. Proteasome activators serve as building blocks to adjust protein turnover in cell growth and differentiation. Understanding the cellular function of proteasome activation in more detail offers a new strategy for therapeutic targeting of proteasomal protein breakdown in disease. The role of the proteasome activator PA200 in cell function and its regulation in disease is unknown. In this study, we investigated the function of PA200 in myofibroblast differentiation and fibrotic tissue remodeling. PA200 was upregulated in hyperplastic basal cells and myofibroblasts of fibrotic lungs from patients with idiopathic pulmonary fibrosis. Increased expression of PA200 and enhanced formation of PA200-proteasome complexes was also evident in experimental fibrosis of the lung and kidney in vivo and in activated primary human myofibroblasts of the lung in vitro. Transient silencing and overexpression revealed that PA200 functions as a negative regulator of myofibroblast differentiation of human but not mouse cells. Our data thus suggest an unexpected and important role for PA200 in adjusting myofibroblast activation in response to pro-fibrotic stimuli, which fails in idiopathic pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Objective: Different risk factors are presumably involved in the pathogenesis of acute respiratory distress syndrome (ARDS) including genetic factors. Clara cell protein 16 (CC16) is a potential candidate gene for ARDS susceptibility because reduced levels of the anti-inflammatory CC16 have been observed in bronchoalveolar lavage fluids or serum of patients with different inflammatory lung diseases. Furthermore, CC16 potently inhibits phospholipase A2, which plays a major role in ARDS pathophysiology. A functional polymorphism (-26G>A) was previously identified and related to decreased CC16 levels, asthma, and asthma severity.Design: Observational study.Settings: Adults with ARDS were recruited from intensive care units in two university medical centers.Subjects: We evaluated the role of this genetic variant in 117 German patients with ARDS and 373 German controls.Measurements: The CC16 -26G>A polymorphism was analyzed by melting-curve analysis using a pair of fluorescence resonance energy transfer probes.Main Results: CC16 genotype frequencies in ARDS patients did not differ from those seen in controls. Also, the allele frequencies were identical in patients compared with controls (0.66 and 0.34). Moreover, only one of the patients who died (n = 27) was homozygous for the -26A allele.Conclusions: The CC16 -26G>A polymorphism does not affect the susceptibility to and the outcome of ARDS. [ABSTRACT FROM AUTHOR]

Impaired immune function contributes to the development of chronic obstructive pulmonary disease (COPD). Disease progression is further exacerbated by pathogen infections due to impaired immune responses. Elimination of infected cells is achieved by cytotoxic CD8+ T cells that are activated by MHC I-mediated presentation of pathogen-derived antigenic peptides. The immunoproteasome, a specialized form of the proteasome, improves generation of antigenic peptides for MHC I presentation thereby facilitating anti-viral immune responses. However, immunoproteasome function in the lung has not been investigated in detail yet. In this study, we comprehensively characterized the function of immunoproteasomes in the human and murine lung. Parenchymal cells of the lung express low constitutive levels of immunoproteasomes, while they are highly and specifically expressed in alveolar macrophages. Immunoproteasome expression is not altered in whole lung tissue of COPD patients. Novel activity-based probes and native gel analysis revealed that immunoproteasome activities are specifically and rapidly induced by IFNγ treatment in respiratory cells in vitro and by virus infection of the lung in mice. Our results suggest that the lung is potentially capable of mounting an immunoproteasome-mediated efficient adaptive immune response to intracellular infections. [ABSTRACT FROM AUTHOR]

An abstract of the article "TGF-β directs trafficking of the epithelial sodium channel ENaC which has implications for ion and fluid transport in acute lung injury," by Dorothea M. Peters and colleagues is presented.

Rationale:Idiopathic pulmonary fibrosis (IPF) is a fatal disease characterized by excessive deposition of extracellular matrix (ECM). Objectives:We investigated the regulation of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) in lung fibrosis. Methods:MMP and TIMP expression, collagenolytic activity and collagen content was assessed in IPF (n=16) versus donor (n=6) lung homogenates and accomplished by in-situ-zymography for gelatinolytic and collagenolytic activities, combined with MMP antigen detection. Role of MMP13 was assessed employing the bleomycin model of lung fibrosis in MMP-13-/- versus wild-type mice. Measurements and Main Results:In IPF, MMPs-1, 2, 7, 9 and 13, but not MMP-8, were significantly upregulated, whereas none of the TIMPs (1–4) were significantly altered. Collagen content was slightly increased and collagenolytic activity was most prominent in the airways and co-localized with MMP-13. We observed an exaggerated early inflammatory response and an augmented lung fibrosis in bleomycin-challenged MMP-13-/- versus wild-type mice, with elevated lung collagen content 28d after bleomycin challenge in the MMP-13-/- mice. Conclusions:Our data suggest that i) collagen deposition in IPF lungs is not primarily due to excessive TIMP production, but rather due to overwhelming ECM production in face of an overall increased, but spatially imbalanced collagenolytic activity, ii) preferential distribution of collagenolytic activity, largely MMP-13, in the airways offers an explanation for the development of honeycomb cysts and iii) despite an overall increase in inflammatory cell content the presence of MMP-13 seems to limit the overall extent of ECM deposition in lung fibrosis. [ABSTRACT FROM AUTHOR]

Abstract: The 2009 European Guidelines on Pulmonary Hypertension did not cover only pulmonary arterial hypertension (PAH) but also some aspects of pulmonary hypertension (PH) in chronic lung disease. These guidelines point out that the drugs currently used to treat patients with PAH (prostanoids, endothelin receptor antagonists and phosphodiesterase type-5 inhibitors) have not been sufficiently investigated in other forms of PH. Therefore, the use of these drugs in patients with chronic lung disease and PH is not recommended. This recommendation, however, is not always in agreement with medical needs as physicians feel sometimes inclined to also treat other forms of pulmonary hypertension which may affect the quality of life and survival of these patients in a similar manner as in PAH. In June 2010, a consensus conference was held in Cologne, Germany, to discuss open and controversial issues surrounding the practical implementation of the European Guidelines. The conference was sponsored by the German Society of Cardiology, the German Society of Respiratory Medicine and the German Society of Pediatric Cardiology (DGK, DGP and DGPK). To this end, a number of working groups were initiated, one of which was specifically dedicated to the diagnosis and treatment of PH due to chronic lung disease. This manuscript describes in detail the results and recommendations of this working group which were last updated in October 2011. [Copyright &y& Elsevier]