Prediction of abdominal CT body composition parameters by thoracic measurements as a new approach to detect sarcopenia in a COVID-19 cohort.

As most COVID-19 patients only receive thoracic CT scans, but body composition, which is relevant to detect sarcopenia, is determined in abdominal scans, this study aimed to investigate the relationship between thoracic and abdominal CT body composition parameters in a cohort of COVID-19 patients. This retrospective study included n = 46 SARS-CoV-2-positive patients who received CT scans of the thorax and abdomen due to severe disease progression. The subcutaneous fat area (SF), the skeletal muscle area (SMA), and the muscle radiodensity attenuation (MRA) were measured at the level of the twelfth thoracic (T12) and the third lumbar (L3) vertebra. Necessity of invasive mechanical ventilation (IMV), length of stay, or time to death (TTD) were noted. For statistics correlation, multivariable linear, logistic, and Cox regression analyses were employed. Correlation was excellent for the SF (r = 0.96) between T12 and L3, and good for the respective SMA (r = 0.80) and MRA (r = 0.82) values. With adjustment (adj.) for sex, age, and body-mass-index the variability of SF (adj. r2 = 0.93; adj. mean difference = 1.24 [95% confidence interval (95% CI) 1.02-1.45]), of the SMA (adj. r2 = 0.76; 2.59 [95% CI 1.92-3.26]), and of the MRA (adj. r2 = 0.67; 0.67 [95% CI 0.45-0.88]) at L3 was well explained by the respective values at T12. There was no relevant influence of the SF, MRA, or SMA on the clinical outcome. If only thoracic CT scans are available, CT body composition values at T12 can be used to predict abdominal fat and muscle parameters, by which sarcopenia and obesity can be assessed.

[Early Pulmonary Rehabilitation after Long Term Mechanical Ventilation]. / Pneumologische Frührehabilitation nach Langzeitbeatmung.

BACKGROUND: The term early rehabilitation is defined as a rehabilitation that begins in the early phase after acute illness and is statutory positioned in §â€Š39SGB V. Aim of this investigation is to describe the quality of outcome of pulmonary early rehabilitation. METHOD: Prospective census of functional parameters, status of ventilation and discharge-disposition in a specialized unit for early pulmonary rehabilitation over a period of one year. RESULTS: Out of 190 patients 179 (94.2 %) were previously invasively ventilated. During the treatment period of 39 ±â€Š17 days, FAM-Index increased from 84.4 ±â€Š19.8 to 118.5 ±â€Š23.3 (Ci 30.9 - 37.3, Cohen'd 1.58; p < 0.001), Barthel-Index from 30.5 ±â€Š13.8 to 58.3 ±â€Š16.2 (Ci 25.4 - 33.8, Cohen's d 1.4; p < 0.001) six minute walking distance from 12.9 ±â€Š40.1 m to 131.4 ±â€Š85.2 m (Ci 105.6 - 131.4 m, Cohn's d 1.78; p < 0.001). Patients were less likely to be receive further post-discharge rehabilitation if they were ventilated. CONCLUSION: Patients admitted to the early pulmonary rehabilitation unit were severely compromised, however quality of outcome was favourable and independent of the breathing status (spontaneously breathing vs. non-invasive ventilation or invasive ventilation). Finding discharge dispositions appeared to be more difficult if patients were ventilated.

[The Overrated Impact of Inhaled Substances (LABA, LAMA, ICS) on Exacerbation Rates in COPD]. / Die überschätzte Beeinflussung der Exazerbationsrate bei COPD durch Inhalativa (LABA, LAMA, ICS).

Numerous studies have shown that exacerbation rates in COPD can be significantly reduced by long acting beta-2-agonists (LABA), long acting anticholinergic agents (LAMA) and inhaled steroids (ICS). Elaborate and extensive investigations however failed to prove that the reduction in exacerbation rates leads to life prolongation. As opposed to this, numerous studies have shown a reduction in life expectancy with increasing number and severity of exacerbations.This review aimed at comparing these studies and to elaborate the relevance and reduction of exacerbations rates by LABA, LAMA and ICS application through effect size calculation by means of Cohens' d. These studies display a common pattern. The reduction of exacerbation rates is only being achieved for less severe exacerbations (Cohens' d max. 0.21). For more severe exacerbations and for the comparison of different substances Cohens' d remains below 0.1, indicating that the effect of the medications is practically irrelevant. The impact of LABA's, LAMA's and ICS on exacerbation rates in COPD patients is obviously overrated.

[Standardization of spirometry: 2015 update. Published by German Atemwegsliga, German Respiratory Society and German Society of Occupational and Environmental Medicine]. / Leitlinie zur Spirometrie. Leitlinie der Deutschen Atemwegsliga, der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin und der Deutschen Gesellschaft für Arbeitsmedizin und Umweltmedizin zur Spirometrie.

Spirometry is a simple test and considered the gold standard in lung function. An obstructive ventilatory defect is a disproportionate reduction of maximal airflow from the lung in relation to the maximal volume that can be displaced from the lung. It implies airway narrowing and is defined by a reduced FEV1/FVC ratio below the 5th percentile of the predicted value (lower limit of normal, LLN). A restrictive disorder may be suspected when vital capacity (FVC) is reduced and FEV1/FVC is normal. It is definitely proven, however, only by a decrease in TLC below the 5th percentile of predicted value (LLN). The measurement of TLC by body plethysmography is necessary to confirm or exclude a restrictive defect or hyperinflation of the lung when FVC is below the LLN. 2012 a task force of the ERS published new reference values based on 74,187 records from healthy non-smoking males and females from 26 countries. The new reference equations for the 3-95 age range are now available that include appropriate age-dependent mean values and lower limits of normal (LLN). This presentation aims at providing the reader with recommendations dealing with standardization and interpretation of spirometry.

Crucial role of Plexin C1 for pulmonary inflammation and survival during lung injury.

Acute pulmonary inflammation during lung injury is initiated by the migration of neutrophils into the alveolar space. The severity of these inflammatory changes within the pulmonary tissue determines the severity of lung injury and ultimately patient outcome. Recent work has demonstrated that the guidance protein Semaphorin 7A propagates the infiltration of neutrophils into an hypoxic tissue site, yet the role of its target receptor Plexin C1 (PLXNC1) during lung injury is to date unknown. We demonstrate here that PLXNC1(+) neutrophils are present within the alveolar space and that PLXNC1 is induced in vitro and in vivo during lung injury. In a model of high-pressure ventilation PLXNC1(-/-) animals show decreased signs of alveolar inflammation and improved survival compared with wild-type controls. Studies employing chimeric animals identified the hematopoietic expression of PLXNC1 to be of crucial importance for the observed results. Functional inhibition of PLXNC1 resulted in improved survival and ameliorated the signs of inflammation within the lung. Furthermore, the injection of a peptide binding to PLXNC1 resulted in improved survival and attenuated pulmonary inflammation. As such we demonstrate here, that previously unknown PLXNC1 holds significant importance for degree of pulmonary inflammation and determines outcome during experimental lung injury.

Economic evaluation of vampire bat (Desmodus rotundus) rabies prevention in Mexico.

Vampire bat rabies causes significant impacts within its endemic range in Mexico. These impacts include livestock mortality, animal testing costs, post-exposure prophylaxis costs, and human mortality risk. Mitigation of the impacts can be achieved by vaccinating livestock and controlling vampire bat populations. A benefit-cost analysis was performed to examine the economic efficiency of these methods of mitigation, and Monte Carlo simulations were used to examine the impact that uncertainty has on the analysis. We found that livestock vaccination is efficient, with benefits being over six times higher than costs. However, bat control is inefficient because benefits are very unlikely to exceed costs. It is concluded that when these mitigation methods are judged by the metric of economic efficiency, livestock vaccination is desirable but bat control is not.

[Weaning from long-term mechanical ventilation: data of a single weaning center from 2007 to 2011]. / Entwöhnung von der Langzeitbeatmung: Daten eines Weaningzentrums von 2007 bis 2011.

INTRODUCTION: Regional weaning centers play a more and more important role in the weaning process of long-term ventilated patients. The medical center Kloster Grafschaft is one of the oldest and largest centers in Germany. There is very little published data from larger weaning centers in Europe. METHODS: From 2007 to 2011 all weaning patients were registered in a database. Additional information of the transferring hospitals was inquired. Prolonged weaning was defined by a period of at least 7 days of mechanical ventilation as well as three unsuccessful weaning trials. RESULTS: Data from 867 of 916 registered patients could be analyzed. 71.1% could be successfully weaned from mechanical ventilation. All patients were suffering from a hypercapnic insufficiency as well as a variety of secondary diagnoses, on average 15.1 per patient. The median of age was 70 years, 62 % were male. Prior to hospital transfer patients had been ventilated for a median of 41 days. Time to successful removal of the artificial airway was 8 days according to the DRG code directive and 13.4 days when non-invasive ventilation (NIV) time was included. Of the 616 patients who could be successfully weaned, 42 % were discharged on NIV. Out of the 251 patients who could not be weaned, 107 were discharged. The remaining 144 (16.7 %) patients died, 33 % due to the primary underlying disease or a complication. 66 % of the deceased patients received palliative care. Patients with successful and unsuccessful weaning did not differ by age, by duration of mechanical ventilation or time until tracheostomy. Postoperative patients could be weaned more often than medical patients (p < 0.05). Discrimination between patients with successful and unsuccessful weaning was not possible by the point in time of the first spontaneous breathing trial in regard to the duration of ventilation but only by the duration of this trial after transfer to our unit (150 vs. 60 min; p < 10-6). The TISS-28 and the SAPS-II-Score did not differ between the two groups. Patients with successful weaning had less agitation according to the RASS-Score (0.47 vs. 0.15; p < 0.005). CONCLUSION: It becomes apparent that in a specialized weaning center the majority of difficult to wean patients can be liberated in short time from mechanical ventilation.

Unwinding of a skyrmion lattice by magnetic monopoles.

Skyrmion crystals are regular arrangements of magnetic whirls that exist in a wide range of chiral magnets. Because of their topology, they cannot be created or destroyed by smooth rearrangements of the direction of the local magnetization. Using magnetic force microscopy, we tracked the destruction of the skyrmion lattice on the surface of a bulk crystal of Fe(1-x)Co(x)Si (x = 0.5). Our study revealed that skyrmions vanish by a coalescence, forming elongated structures. Numerical simulations showed that changes of topology are controlled by singular magnetic point defects. They can be viewed as quantized magnetic monopoles and antimonopoles, which provide sources and sinks of one flux quantum of emergent magnetic flux, respectively.

[Scope and limitations of the median nerve mouse model in research on peripheral nerve regeneration]. / Möglichkeiten und Grenzen des N. medianus Maus Modells bei der Erforschung der peripheren Nervenregeneration.

INTRODUCTION: Peripheral nerve regeneration is usually studied in rat animal models (N. medianus or N. ischiadicus). In this article, we further evaluate the mouse median nerve model with its advantages and possible pitfalls. MATERIALS AND METHODS: 24 mice (C57BL/6) were operated. The median nerve was exposed in the left axilla. After transection, immediate microsurgical repair followed using 11/0 sutures. In the contralateral axilla, 1 cm of median nerve was resected. After the operation, functional regeneration of the median nerve was assessed using the grasping test. Histological analysis was performed after staining with toluidine blue. RESULTS: All animals survived the procedure. Grip strength increased starting at day 10 and reached its maximum at day 35. Myelinated fibres in the regenerated nerves showed a smaller diameter and a thinner myelin sheath and the typical microfasciculation of regenerated nerve fibres in comparison to the uninjured nerve. CONCLUSION: The mouse median nerve model is technically demanding but opens a wide field of possible research options using genetically modified mice.

Patchiness of embedded particles and film stiffness control through concentration of gold nanoparticles.

Patchy particles are fabricated using a method of embedding-into and extracting-from thick, biocompatible, gel-like HA/PLL films. Control over the patchiness is achieved by adjusting the stiffness of films, which affects embedding and masking of particles. The stiffness is adjusted by the concentration of gold nanoparticles adsorbed onto the surface of the films.

Body plethysmography--its principles and clinical use.

Body plethysmography allows to assess functional residual capacity (FRC(pleth)) and specific airway resistance (sRaw) as primary measures. In combination with deep expirations and inspirations, total lung capacity (TLC) and residual volume (RV) can be determined. Airway resistance (Raw) is calculated as the ratio of sRaw to FRC(pleth). Raw is a measure of airway obstruction and indicates the alveolar pressure needed to establish a flow rate of 1 L s(-1). In contrast, sRaw can be interpreted as the work to be performed by volume displacement to establish this flow rate. These measures represent different functional aspects and should both be considered. The measurement relies on the fact that generation of airflow needs generation of pressure. Pressure generation means that a mass of air is compressed or decompressed relative to its equilibrium volume. This difference is called "shift volume". As the body box is sealed and has rigid walls, its free volume experiences the same, mirror image-like shift volume as the lung. This shift volume can be measured via the variation of box pressure. The relationship between shift volume and alveolar pressure is assessed in a shutter maneuver, by identifying mouth and alveolar pressure under zero-flow conditions. These variables are combined to obtain FRC(pleth), sRaw and Raw. This presentation aims at providing the reader with a thorough and precise but non-technical understanding of the working principle of body plethysmography. It also aims at showing that this method yields significant additional information compared to spirometry and even bears a potential for further development.