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Recent advances in computer vision have led to significant progress in the generation of realistic image data, with denoising diffusion probabilistic models proving to be a particularly effective method. In this study, we demonstrate that diffusion models can effectively generate fully-annotated microscopy image data sets through an unsupervised and intuitive approach, using rough sketches of desired structures as the starting point. The proposed pipeline helps to reduce the reliance on manual annotations when training deep learning-based segmentation approaches and enables the segmentation of diverse datasets without the need for human annotations. We demonstrate that segmentation models trained with a small set of synthetic image data reach accuracy levels comparable to those of generalist models trained with a large and diverse collection of manually annotated image data, thereby offering a streamlined and specialized application of segmentation models., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Eschweiler et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: In patients with obstructive sleep apnea syndrome (OSAS), the preference-based, health-related quality of life in terms of utility has not been extensively studied., Objective: To address this point, we compared the performance of different instruments assessing utility in patients with OSAS undergoing continuous positive airway pressure (CPAP) therapy., Materials and Methods: Data of 208 patients with OSAS (28 women, mean ± SE age 54.4 ± 0.7 years, apnea-hypopnea index (AHI) 51.9 ± 1.8/h, Epworth sleepiness score 13.4 ± 0.2) participating in a randomized trial of different CPAP modalities over 2 years were analyzed. Evaluations included sleep studies, Epworth sleepiness scale, and several utility instruments that measure subjective health preference on a scale ranging from 1 (most preferred and perfect health) to 0 (least preferred and very poor health)., Results: After 2 years of CPAP therapy, the mean ± SE AHI was 6.7 ± 1.5/h and Epworth score 7.9 ± 0.4, both p < 0.001 versus baseline. Baseline utilities and changes (95% confidence interval) after 2 years of CPAP therapy were EuroQol 5-dimensions 0.79 ± 0.01, 0.02 (0.00-0.05, p = 0.064); short-form 6-dimension medical outcome questionnaire 0.72 ± 0.01, 0.06 (0.04-0.08, p < 0.001); Euro-thermometer visual analog scale 0.70 ± 0.01, 0.09 (0.07-0.12, p < 0.001); time trade-off 0.82 ± 0.01, 0.03 (0.01-0.06, p = 0.002); and standard gamble 0.82 ± 0.01, -0.01 (-0.03 to 0.02, p = 0.712)., Conclusion: The short-form 6-dimensions questionnaire, the Euro-thermometer, and the time trade-off instruments reflected the major clinical improvements in OSAS, while the EuroQoL 5-dimensions and standard gamble tests were not sensitive to CPAP effects. These results indicate that the evaluation of utility of a treatment for OSAS depends critically on the instrument used, which is important from an individual and societal perspective., (© 2021 The Author(s) Published by S. Karger AG, Basel.)

Antisynthetase syndrome is a rare autoimmune disease and represents a distinct entity within the idiopathic inflammatory myopathies. Its variable systemic manifestations are composed of myositis, interstitial lung disease, non-erosive arthritis, fever, Raynaud's phenomenon, hyperkeratotic skin changes and the presence of antibodies against aminoacyl-transfer-RNA-synthetases. Interstitial lung disease is the major determinant of morbidity and mortality. The role of lung biopsy remains controversial but it might be considered on an individual basis and may provide information regarding prognosis and treatment response. An integrated clinical, radiological and pathological approach to interstitial lung disease has to be emphasised. Due to the rarity of the disease, no standardised treatment guidelines for antisynthetase syndrome exist. We discuss a patient with anti-Jo1-autoantibody antisynthetase syndrome with proximal myositis and severe, rapid onset, interstitial lung disease with a histopathological pattern of organising pneumonia on surgical lung biopsy and good response to early combined immunosuppressive treatment with corticosteroids, mycophenolate mofetil and rituximab., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Pulmonary Infiltrate - Not Always Due to Bacterial Infection Abstract. A 65-year-old female patient with a history of controlled asthma was diagnosed with community-acquired pneumonia (CAP). After two weeks of treatment on co-amoxicillin, she failed to respond and was referred for further investigations. Clinical symptoms and laboratory results were suggestive for eosinophilic granulomatosis with polyangiitis (EGPA). Diagnosis and treatment of this disease are still challenging, especially in cases with vital organ involvement.

Background: The obstructive sleep apnoea syndrome (OSAS) is conventionally treated by continuous positive airway pressure set at a fixed level (fCPAP). Automatic mask pressure adjustment (autoCPAP) is increasingly used during home therapy. We investigated whether autoCPAP is equivalent to fCPAP in improving sleepiness in patients with OSAS in the long-term., Methods: In this multicentre equivalence trial, 208 patients with OSAS, with median Epworth sleepiness score (ESS) 13, apnoea/hypopnoea index 48.4/hour, were randomised to treatment with autoCPAP (5-15 mbar) or fCPAP (pressure set at the 90th percentile applied by autoCPAP during 2-4 weeks adaptation). Coprimary outcomes were changes in subjective and objective sleepiness from baseline to 2 years after treatment. Equivalence ranges were ±2 points in ESS and ±3 min sleep resistance time evaluated by recording responses to light signals., Results: At 2 years, in the intention to treat analysis, the reduction in sleepiness versus pretreatment baseline was similar in patients using autoCPAP (n=113, mean ESS-change -6.3, 95% CI -7.1 to -5.5; sleep resistance time +8.3 min, +6.9 to +9.7) and fCPAP (n=95, mean ESS-change -6.2, 95% CI -7.0 to -5.3; sleep resistance time +6.3 min, +4.7 to +7.8). The 95% CI of difference in ESS-reduction between autoCPAP and fCPAP was -0.9 to +1.4 and the 95% CI of difference in increase in sleep resistance time was -2.6 to +1.0 min. Blood pressure reduction and OSAS-related costs were similar between groups., Conclusions: AutoCPAP and fCPAP are equivalent within prespecified ranges in improving subjective and objective sleepiness in patients with OSAS over the course of 2 years. Costs of these treatments are similar., Trial Registration Number: ClinicalTrials.gov NCT00280800., Competing Interests: Competing interests: KEB reports grants to his institution from Swiss National Science Foundation, Zurich Lung League, Respironics Foundation, ResMed Switzerland, during the conduct of the study. The other authors report no competing interests., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Limited resources for the in-depth processing of external stimuli make it necessary to select only relevant information from our surroundings and to ignore irrelevant stimuli. Attentional mechanisms facilitate this selection via top-down modulation of stimulus representations in the brain. Previous research has indicated that acetylcholine (ACh) modulates this influence of attention on stimulus processing. However, the role of muscarinic receptors as well as the specific mechanism of cholinergic modulation remains unclear. Here we investigated the influence of ACh on feature-based, top-down control of stimulus processing via muscarinic receptors by using a contingent capture paradigm which specifically tests attentional shifts toward uninformative cue stimuli which display one of the target defining features In a double-blind, placebo controlled study we measured the impact of the muscarinic receptor antagonist scopolamine on behavioral and electrophysiological measures of contingent attentional capture. The results demonstrated all the signs of functional contingent capture, i.e., attentional shifts toward cued locations reflected in increased amplitudes of N1 and N2Pc components, under placebo conditions. However, scopolamine did not affect behavioral or electrophysiological measures of contingent capture. Instead, scopolamine reduced the amplitude of the distractor-evoked Pd component which has recently been associated with active suppression of irrelevant distractor information. The findings suggest a general cholinergic modulation of top-down control during distractor processing.

Background: Although sevoflurane (Sevo) had been shown to ameliorate posttransplant injury in various organs, data available are inconsistent, particularly in the context of lung transplantation (Tx). We here investigated if preconditioning by Sevo can protect from posttransplant injury regarding both, primary graft dysfunction (PGD) and acute rejection (AR) after experimental lung Tx, thereby focusing on two important clinical outcome parameters., Materials and Methods: Three experimental approaches were used: (1) BALB/c mice were preconditioned for 2 h with Sevo or a fentanyl cocktail (Control; n = 10); (2) syngeneic (Syn) mouse lung Tx (C57BL/6) with a Sevo-preconditioned graft followed by 18 h storage to mimic PGD (Syn-Tx, n = 12) versus controls (fentanyl cocktail); and (3) allogeneic (Allo) Tx (BALB/c, donor; C57BL/6, recipient) to mimic AR (Allo-Tx, n = 12) versus controls (fentanyl cocktail). Syn-Tx grafts were harvested on Day 1, Allo-Tx grafts on Day 3 and analyzed for histology, immunohistochemistry, blood gas analysis, and inflammatory cytokines (enzyme-linked immunosorbent assay or reverse transcription polymerase chain reaction)., Results: Evaluating the preconditioning effect of Sevo only showed significantly better oxygenation (P = 0.03) and a tendency toward lower levels of lung tissue messenger RNA for tumor necrosis factor-α. In Syn-Tx recipients, the Sevo group had histologically a tendency toward an attenuation of PGD and showed significantly lower levels of interleukin 6 (P = 0.01) in plasma, but higher levels of interleukin 10 (P < 0.01) in lungs. Allo-Tx grafts in Sevo Tx recipients showed attenuated AR with histologically significantly lower rejection scores (P = 0.03), fewer classical macrophages (F4/80+; P < 0.01), but more anti-inflammatory activated macrophages (M2, CD206+; P < 0.01). Functionally, the Sevo group had a tendency toward improved oxygenation., Conclusions: We demonstrated that Sevo preconditioning has protective effects on lung transplants in both, PGD and AR. The observed amelioration may be attributed to suppressed inflammatory cytokines during PGD and the induction of alternatively activated macrophages during AR. These promising data could set the base for using Sevo preconditioning in donor lungs for a human trial., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Neglect patients typically show a rightward attentional orienting bias and a strong disengagement deficit, such that they are especially slow in responding to left-sided targets after right-sided cues (Posner et al., 1984). Prism adaptation (PA) can reduce diverse debilitating neglect symptoms and it has been hypothesized that PA's effects are so generalized that they might be mediated by attentional mechanisms (Pisella et al., 2006; Redding and Wallace, 2006). In neglect patients, performance on spatial attention tasks improves after rightward-deviating PA (Jacquin-Courtois et al., 2013). In contrast, in healthy subjects, although there is evidence that leftward-deviating PA induces neglect-like performance on some visuospatial tasks, behavioral studies of spatial attention tasks have mostly yielded negative results (Morris et al., 2004; Bultitude et al., 2013). We hypothesized that these negative behavioral findings might reflect the limitations of behavioral measures in healthy subjects. Here we exploited the sensitivity of event-related potentials to test the hypothesis that electrophysiological markers of attentional processes in the healthy human brain are affected by PA. Leftward-deviating PA generated asymmetries in attentional orienting (reflected in the cue-locked N1) and in attentional disengagement for invalidly cued left targets (reflected in the target-locked P1). This is the first electrophysiological demonstration that leftward-deviating PA in healthy subjects mimics attentional patterns typically seen in neglect patients. Significance statement: Prism adaptation (PA) is a promising tool for ameliorating many deficits in neglect patients and inducing neglect-like behavior in healthy subjects. The mechanisms underlying PA's effects are poorly understood but one hypothesis suggests that it acts by modulating attention. To date, however, there has been no successful demonstration of attentional modulation in healthy subjects. We provide the first electrophysiological evidence that PA acts on attention in healthy subjects by mimicking the attentional pattern typically reported in neglect patients: both a rightward attentional orienting bias (reflected in the cue-locked N1) and a deficit in attentional disengagement from the right hemispace (reflected in the target-locked P1). This study makes an important contribution to refining current models of the mechanisms underlying PA's cognitive effects., (Copyright © 2016 the authors 0270-6474/16/361019-12$15.00/0.)

Chest-wall invading malignancies usually necessitate the resection of the respective part of the thoracic wall. Gore-Tex® is the material of choice that is traditionally used to repair thoracic defects. This material is well accepted by the recipient; however, though not rejected, it is an inert material and behaves like a 'foreign body' within the thoracic wall. By contrast, there are materials that have the potential to physiologically integrate into the host, and these materials are currently under in vitro and also in vivo investigation. These materials offer a gradual but complete biodegradation over time, and severe adverse inflammatory responses can be avoided. Here, we present a novel material that is a biodegradable nanocomposite based on poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles in comparison to the traditionally employed Gore-Tex® being the standard for chest-wall replacement. On a mouse model of thoracic wall resection, that resembles the technique and localization applied in humans, poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles and Gore-Tex® were implanted subcutaneously and additionally tested in a separate series as a chest-wall graft. After 1, 2, 4 and 8 weeks cell infiltration into the respective materials, inflammatory reactions as well as neo-vascularization (endothelial cells) were determined in six different zones. While Gore-Tex® allowed for cell infiltration only at the outer surface, electrospun poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles were completely penetrated by infiltrating cells. These cells were composed mainly by macrophages, with only 4% of giant cells and lymphocytes. Total macrophage count increased by time while the number of IL1-β-expressing macrophages decreased, indicating a protective state towards the graft. As such, poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles seem to develop ideal characteristics as a material for chest-wall replacement by (a) having the advantage of full biodegradation, (b) displaying stable chest-wall structures and (c) adapting a physiological and integrating graft compared to Gore-Tex®., (© The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Based on a dataset comprising coding DNA sequences of 23 anthropoid primates, we herein investigate if rates of sequence evolution of SPerm Adhesion Molecule1 (SPAM1, also PH-20), which participates in sperm-egg interaction, is lower in more sexually dimorphic species. For comparison, we analyze sequence evolution of apolipoproteinA-IV (APOA4) and apolipoprotein A-V (APOA5), which should evolve under less or even no sexual selection given their expression in blood, digestive tract, liver, and lungs. Regression analyses provides significant support for a negative dependence of SPAM1 derived branch-specific ratios of non-synonymous to synonymous substitution rates (dN/dS) on sexual size dimorphism (SSD) in a subsample comprising New World and Old World monkeys. We moreover observed a tendency for a positive correlation of substitution rates of SPAM1 with relative testes weight (RTW) and significantly lowered dN/dS estimates in uni-male and uni-male/multi-male breeding monkeys. Importantly, the pattern was not reproduced when analyzing partial APOA4 and APOA5 sequences. These findings illustrate that different levels of sperm competition, probably fueled by female cryptic choice, account for species-specific sequence evolution of SPAM1 in monkeys. Remarkably, present data do not support a correlation of species-specific sequence evolution of SPAM1 with sexual selection levels in hominoids (apes including humans). This can partly be ascribed to a relaxation of functional constraint of SPAM1 in some hominoid species. Additional factors confounding regression analyses specifically in hominoids might be higher levels of sperm competition than reflected by SSD and RTW in some species, a rather strong effect of female mate choice on paternity rates in others, and - in particular in humans - socio-cultural factors not measurable by SSD and RTW., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Land-use intensification is a major cause for the decline in species diversity in human-modified landscapes. The loss of functionally important species can reduce a variety of ecosystem functions, such as pollination and seed dispersal, but the intricate relationships between land-use intensity, biodiversity and ecosystem functioning are still contentious. Along a gradient from forest to intensively used farmland, we quantified bee species richness, visitation rates of bees and pollination success of wild cherry trees (Prunus avium). We analysed the effects of structural habitat diversity at a local scale and of the proportion of suitable habitat around each tree at a landscape scale. We compared these findings with those from previous studies of seed-dispersing birds and mammals in the same model system and along the same land-use gradient. Bee species richness and visitation rates were found to be highest in structurally simple habitats, whereas bird species richness--but not their visitation rates--were highest in structurally complex habitats. Mammal visitation rates were only influenced at the landscape scale. These results show that different functional groups of animals respond idiosyncratically to gradients in habitat and landscape structure. Despite strong effects on bees and birds, pollination success and bird seed removal did not differ along the land-use gradient at both spatial scales. These results suggest that mobile organisms, such as bees and birds, move over long distances in intensively used landscapes and thereby buffer pollination and seed-dispersal interactions. We conclude that measures of species richness and interaction frequencies are not sufficient on their own to understand the ultimate consequences of land-use intensification on ecosystem functioning.

Previous fMRI experiments showed an involvement of the STS in the processing of eye-gaze direction in joint attention. Since head-gaze direction can also be used for the assessment of another person's attentional focus, we compared the mechanisms underlying the processing of head- and eye-gaze direction using a combined psychophysical and fMRI approach. Subjects actively followed the head- or eye-gaze direction of a person in a photograph towards one of seven possible targets by moving their eyes. We showed that the right posterior superior temporal sulcus (STS) as well as the right fusiform gyrus (FSG) were involved in both processing of head- as well as eye-gaze direction. Another finding was a bilateral deactivation of a distinct area in the middle STS (mSTS) as well as the left anterior STS (aSTS), that was stronger when subjects followed eye-gaze direction than when they followed head-gaze direction. We assume that this deactivation is based on an active suppression of information arising from the distracting other directional cue, i.e. head-gaze direction in the eye-gaze direction task and eye-gaze direction in the head-gaze direction task. These results further support the hypothesis that the human equivalent of the gaze sensitive area in monkeys lies in more anterior parts of the STS than previously thought., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Only few studies have analysed the relationship between biodiversity and ecosystem function at the landscape scale although relationships and mechanisms known from experimental studies might be different in natural systems. We quantified bird diversity and seed removal from 38 wild cherry trees (Prunus avium) along a human land-use gradient from forest to structurally diverse to simple agricultural systems. High human land-use intensity led to low species richness and total abundance of the local bird community around wild cherry trees, as expected from previous studies. Nevertheless, trees in structurally simple agroecosystems were visited as frequently as trees in structurally complex landscapes and in forests. Furthermore, the number of seeds removed per tree did not decline with increasing human land-use intensity. Thus, ecosystem function was robust in spite of locally reduced bird diversity. The reason might be that movement behaviour and movement distances of birds changed along the human land-use gradient. It appears that birds moved longer distances to forage in fruiting cherry trees in structurally simple agroecosystems. This suggests that for systems where ecosystem function is mediated by highly mobile organisms, movement behaviour and distances are of considerable importance. Increases in movement distances with increasing human land-use intensity might also be common in other systems in which ecosystem function depends on mobile links.

1. Dispersal is one of the key ecological parameters but it is very difficult to quantify directly. As a consequence, empirical studies often ignore dispersal or use indirect measures. 2. Ringing data have previously been used to estimate the natal dispersal distances of 47 British passerine bird species. This provides an excellent opportunity to examine the potential of various indirect measures to predict natal dispersal distances in British birds. 3. We use a phylogenetic comparative framework and single- and multipredictor models including ecomorphological, behavioural or ecological traits to predict natal dispersal distance. 4. A multipredictor model that includes Kipp's distance (a measure of wing tip length), bill depth and tail graduation explains 45% of the interspecific variation in natal dispersal distance. These morphological characters all relate to aerodynamics with stronger flyers dispersing further. 5. However, an index of migration is a strong (but less informative) correlate of dispersal distance and Kipp's distance and bill depth are strong correlates of migration. Thus, we cannot disentangle whether these ecomorphological traits influence dispersal distance directly or whether the relationship between ecomorphology and dispersal is mediated through migratory behaviour. 6. Notwithstanding uncertainties regarding the causal links between dispersal distance and wing morphology, we suggest that two ecomorphological traits, Kipp's distance and bill depth, may provide a useful surrogate.

Background: Patients with central serous chorioretinopathy (CSC) show an increased sympathetic activity compared to controls. Additionally, there are several reports of increased corticosteroid and catecholamine levels in these patients. Obstructive sleep apnea syndrome (OSAS) has been shown to enhance sympathetic activity depending on severity. Respiratory disturbance increases urinary catecholamine secretion and is associated with the occurence of hypertension in a dose dependent manner. Therefore we hypothesize that OSAS may act as a risk factor for the development of CSC., Methods: Patients with active CSC or with pigment epithelial disturbances after CSC were contacted to answer a questionnaire about general health, drugs and sleeping habits and to complete the Epworth Sleepiness Scale (ESS) score, a widely used subjective measure of daytime sleepiness. Patients with an ESS score of >10 were referred to our department of pulmonary medicine for evaluating of respiratory disturbance in sleep., Results: We identified 56 consecutive patients with angiographic criteria for acute CSC or pigment epithelial defects after CSC, seven (12.5%) of whom were excluded because of a history of systemic or topic corticosteroid use. Thirty-six (73.5%) of the remaining 49 patients returned the questionnaire. Fourteen (38.8%) had an ESS score of >10. They were referred to the Department of Pulmonary Medicine. In eight (22.2%) of these patients, a diagnosis of obstructive sleep apnea syndrome was confirmed., Conclusions: We found that 22% of the patients with acute or chronic CSC in this case series also suffered from OSAS, whereas in the general population OSAS is considerably less frequently reported (2-4%). OSAS therefore may act as a risk factor for the development of CSC. However, prospective controlled data is needed to definitely evaluate the possible association between CSC and OSAS. Also the clinical course of CSC during treatment of OSAS would be of particular interest.

Background: Sleep related breathing disorders (SBD) are common and associated with morbidity and mortality. Since polysomnography, the conventional diagnostic gold standard is costly and not generally available, ambulatory respiratory polygraphic sleep studies (RP) are used. To evaluate whether RP reimbursement by health insurance companies was justified, the Swiss Federal Office of Public Health (FOPH) requested registration of RP during 36 months and a literature review on RP. The results are reported here., Methods: RP reimbursed from July 2002 to December 2005 by Swiss health insurance companies were analysed. A review of the literature from 2003 comparing RP with PSG was updated. The outcome of interest was the apnoea/hypopnoea index., Results: Datasets on 11,485 RP were evaluated, 8179 were performed to evaluate suspected obstructive sleep apnoea syndrome (OSAS). In patients with snoring, witnessed apnoea and hypersomnia (n = 4180), 80.2% of RP confirmed OSAS, 3.5% of RP were inconclusive prompting polysomnography. Six studies published between 2003 and 2005 were pooled with a former review of 12 studies. With a mean pre-test probability of 64% for OSAS, the post-test probability after a negative result ranged from 8% (negative likelihood ratio of 0.05) to 23% (negative likelihood ratio of 0.20). The post-test probability after a positive result was within a range of 98% (positive likelihood ratio of 23.8) to 90% (positive likelihood ratio of 5.7)., Conclusions: In selected patients with clinically suspected OSAS RP allows accurate and simple diagnosis of OSAS. According to the practice in Switzerland as reflected by the registry additional PSG are rarely required, suggesting relevant cost savings by RP. Granting reimbursement for RP as introduced in the meantime by the FOPH seems justified.

Chronic infectious rhinosinusitis with Pseudomonas aeruginosa is common in cystic fibrosis and may result in allograft infection after lung transplantation. Sinus surgery followed by nasal care may reduce these adverse effects. Sinus surgery was performed in 37 patients with cystic fibrosis after transplantation. Bacteriology of sinus aspirates (n=771) and bronchoalveolar lavage (BAL) (n=256) was correlated with clinical data. Sinus surgery was successful in 54% and partially successful in 27% of patients. A significant correlation between negative sinus aspirates and negative BAL and between positive sinus aspirates and positive BAL (P<0.0001) was found. Successful sinus management led to a lower incidence of tracheobronchitis and pneumonia (P=0.009) and a trend toward a lower incidence of bronchiolitis obliterans syndrome (P=0.23). Sinus surgery followed by daily nasal douching may control posttransplant lower airway colonization and infection. In the long term, this concept may lead to less bronchiolitis obliterans syndrome by decreasing bronchiolar inflammation.

Excessive sleepiness is a common but underrecognised and preventable cause of road traffic accidents. Acute and chronic sleep deprivation, inadequate sleep hygiene, and sleep disorders are important causes of hypersomnolence. Since the latter is one of the cardinal manifestations of the obstructive sleep apnoea syndrome, affected patients are at particular risk of being involved in traffic accidents. Counselling of hypersomnolent drivers on appropriate behavioural modification, early diagnosis and treatment of sleep disorders, as well as information of the public on the risks of accidents related to sleepiness are important preventive measures.

Background: Lung volume reduction surgery (LVRS) improves dyspnea, pulmonary function, and quality of life in selected patients with severe emphysema. We investigated the role of emphysema morphology in 37 patients as an outcome predictor for up to 2 years after operation., Methods: Patients selected for bilateral thoracoscopic LVRS were divided, according to a simplified emphysema morphology classification, into three groups (homogeneous, moderately heterogeneous, and markedly heterogeneous) based on a preoperative chest computed tomogram. Pulmonary function, walking distance, and dyspnea were assessed., Results: Functional improvement after LVRS was best in markedly heterogeneous emphysema with an increase from preoperative forced expiratory volume in 1 second of 31% +/- 2% (mean +/- standard error of the mean) to 52% +/- 4% of predicted postoperatively. It was significantly higher than in homogeneous emphysema (from 26% +/- 1% to 38% +/- 2% predicted) and in intermediately heterogeneous emphysema (from 29% +/- 2% to 44% +/- 45% predicted). At 24 months postoperatively, forced expiratory volume in 1 second and dyspnea score continued to be significantly better than preoperative levels in all three morphologic groups. The survival rate was highest in patients with markedly heterogeneous emphysema., Conclusions: Functional and subjective improvements were maintained after LVRS for at least 24 months in patients with heterogeneous or homogeneous emphysema type.

We tested the practicability of dipyridamole myocardial nitrogen-13 ammonia positron emission tomography (dipyridamole (13)NH(3 )PET) for the perioperative risk assessment of coronary artery disease (CAD) in a cohort of patients with severe chronic obstructive pulmonary disease (COPD) undergoing lung volume reduction surgery (LVRS). Twenty consecutive LVRS candidates, 13 men and 7 women (mean age 57+/-2 years), without symptoms of CAD were prospectively studied by dipyridamole (13)NH(3 )PET. Side-effects and overall tolerance were assessed by a questionnaire and visual analogue scale. Repeated pulmonary function tests were performed before and 4, 12, 16 and 30 minutes after dipyridamole injection. All dipyridamole (13)NH(3 )PET studies were negative for CAD. Seventeen patients underwent LVRS without cardiac complications; three patients did not undergo LVRS for other reasons. Nine patients suffered intolerable dyspnoea requiring i.v. aminophylline. Mean FEV(1) decreased significantly after dipyridamole infusion: in nine patients the reduction in FEV(1)exceeded 15% from baseline. We found that dipyridamole is not well tolerated and causes significant bronchoconstriction in patients with severe COPD. Although all dipyridamole-induced side effects can be promptly reversed by aminophylline, dipyridamole cannot be recommended as a pharmacological stress in this setting.

Non-invasive ventilation refers to ventilatory support without establishing an endotracheal airway. The advent positive-pressure ventilation delivered through a nasal or face mask has greatly expanded the use of non-invasive ventilation. In patients with acute respiratory failure due to chronic obstructive lung disease, non-invasive positive pressure ventilation reduces the need for intubation and related complications, shortens the duration of hospital stay and improves survival. The role of intermittent non-invasive long-term ventilation in the management of chronic respiratory failure related to chronic obstructive lung disease remains to be defined. The advantages of this therapy as an adjunct to conventional medical treatment and long-term oxygen therapy are not well established. Introduction of non-invasive ventilation requires close monitoring by experienced staff. Technical advances in delivery systems have improved the results and acceptance of this promising therapy.

Bacterial pneumonias are the most common pulmonary complication in HIV-infected patients. Up to now, H. influenzae and S. pneumoniae have been described as the most important germs. Within a period of 4 years we diagnosed 15 cases of pneumonia caused by P. aeruginosa. All patients were in HIV stage C3; 3F, 12M; median age 34 (24-54) years; median CD4 count 10 (0-130) microliters. Except for 3 nosocomial pneumonias, all others were community-acquired. Only 3 patients had neutropenia < 1000/microliter; 7 were intravenous drug abusers. Morphologically there were 6 cases of abscess pneumonia, in 3 of which pleural drainage was necessary because of pyopneumothorax. 4 patients showed bilateral infiltrates that could not be differentiated from those of P. carinii pneumonia. Our diagnosis was based on quantitative cultures of broncho-alveolar lavage fluid (9 cases, two of them with concurrent positive blood cultures/positive cultures of the pleural fluid), pleural puncture (one case), sputum in pneumonias responding only to antipseudomonas therapy (3 cases), and autopsy (2 cases). 8 patients died of pseudomonas pneumonia within 1-3 months despite therapy. 7 patients received pseudomonas-specific combination therapy, but all died after median 9 (4-15) months of the underlying illness. In 3 cases recurrent pseudomonas pneumonia could be documented bacteriologically. We conclude that in HIV-infected patients pneumonia caused by P. aeruginosa is a significant and severe pulmonary complication.

Lung perfusion scintigraphy is employed to evaluate patients with severe emphysema who are candidates for lung volume reduction surgery (LVRS). Our purpose was to investigate the role of scintigraphy in relation to chest computed tomography (CT) and lung function in this setting. Six observers blinded to clinical data retrospectively scored preoperative scintigrams of 70 patients undergoing bilateral video-assisted LVRS according to the distribution of lung perfusion as homogeneous, intermediately heterogeneous, or markedly heterogeneous. Heterogeneity of emphysema distribution was also assessed by chest CT. Dyspnea and pulmonary function were measured preoperatively and 3 mo postoperatively. In 42 patients with markedly heterogeneous, in 18 with intermediately heterogeneous, and in 10 with homogeneous perfusion, mean (+/- SE) FEV1 increased by 57 +/- 8% (p < 0.0001), 38 +/- 9% (p < 0.001), and 23 +/- 9% (p = NS) (p = NS for intergroup comparisons). In a multiple regression analysis, functional improvement after LVRS was more closely correlated with preoperative hyperinflation and the degree of emphysema heterogeneity estimated by chest CT than with the degree of perfusion heterogeneity assessed by scintigraphy. In 16 of 22 patients with homogeneous emphysema distribution in the chest CT scintigraphy revealed intermediately or markedly heterogeneous perfusion. We conclude that lung perfusion scintigraphy has a limited role in prediction of outcome, but it may help to identify target areas for resection in LVRS candidates with homogeneous CT morphology.

Sleepiness is a major cause of traffic accidents. Our purpose was to review determinants of accidents related to sleepiness and measures to prevent them. We performed a systematic literature review on the topic and studied official accident statistics and legislation regarding medical driving ability in Switzerland. In 1997, 79,178 road traffic accidents, each causing bodily injury or property damage in excess of 500 Swiss francs, occurred in Switzerland. According to official statistics, sleepiness accounted for only 1% of identified causes. However, scientific studies performed in other countries suggest that sleepiness is a contributing factor in up to 30% of traffic accidents. Causes of hypersomnolence are sleep restriction, sleep disturbance by external environmental factors, inappropriate sleep hygiene, and sleep disorders. Several reports suggest an increased crash rate in patients with obstructive sleep apnoea syndrome. At our clinic, every sixth sleep apnoea patient reports sleepiness-related driving problems which resulted in traffic accidents in one third of them. Long monotonous motorway drives, late night, early morning and late afternoon hours are associated with an increased crash rate. Drivers with excessive sleepiness should not drive until the cause of hypersomnolence is determined and treated appropriately. Medical assessment of driving ability in patients with sleep disorders involves a specific history including standardised questionnaires, sleep studies and vigilance tests. Swiss legislation authorizes physicians to report sleepy drivers to the authorities if they are thought to represent an accident risk for themselves or others. We conclude that sleepiness is a common but under-recognised cause of traffic accidents. Enhancing awareness of the problem in the public, early recognition and treatment of sleep disorders, and counselling of drivers with excessive sleepiness may contribute to prevention.