Harmonization of growth hormone measurements with different immunoassays by data adjustment

Background: The aim of our study was to evaluate the between-assay variability of commercially available immunoassays for the measurement of human growth hormone (hGH). In addition, we asked whether the comparability of the diagnosis of childhood onset growth hormone deficiency could be improved by adjusting hGH results by statistical methods, such as linear regression, conversion factors, and quantile transformation. Methods: In archived sera from 312 children and adolescents (age: 17 days-17 years) hGH values between 0.01 and 16.5 ng/mL were determined by using the following immunoassays: AutoDELFIA (PerkinElmer), BC-IRMA (Beckman-Coulter), ELISA (Mediagnost), IMMULITE 2000 (Siemens), iSYS (IDS), Liaison (DiaSorin), UniCel DxI 800 Access (BeckmanCoulter) and "In house"-RIA (Tubingen). Results: The assays differed in median hGH concentrations by as much as 5.44 ng/mL (Immulite), and as little as 2.67 ng/mL (BC-IRMA). The mean difference between assays ranged from 0.35 to 2.71 ng/mL, whereas several samples displayed differences up to 11.4 ng/mL. The best correlation (r=0.992) was found between AutoDELFIA and Liasion, the lowest (r=0.864) was between an in-house RIA and iSYS. The between-assay CV (mean +/- SD) of values within the cut-off range was 24.3%+/- 7.4%, resulting in an assay-dependent diagnosis of growth hormone deficiency (GHD) in more than 27% of patients. Yet, adjustment of this data by linear regression or a conversion factor reduced the CV below 14%, and the ratio of assay-dependent diagnoses below 8%. Using quantile transformation, the CV and ratio were reduced to 11.4% and < 1%, respectively. Conclusions: hGH measurements using different assays vary significantly. Linear regression, conversion factors, or particularly quantile transformation are useful tools to improve comparability in the diagnostic procedure for the confirmation of GHD in childhood and adolescence

Formation of cristae and crista junctions in mitochondria depends on antagonism between Fcj1 and Su e/g

Crista junctions (CJs) are important for mitochondrial organization and function, but the molecular basis of their formation and architecture is obscure. We have identified and characterized a mitochondrial membrane protein in yeast, Fcj1 (formation of CJ protein 1), which is specifically enriched in CJs. Cells lacking Fcj1 lack CJs, exhibit concentric stacks of inner membrane in the mitochondrial matrix, and show increased levels of F1FO–ATP synthase (F1FO) supercomplexes. Overexpression of Fcj1 leads to increased CJ formation, branching of cristae, enlargement of CJ diameter, and reduced levels of F1FO supercomplexes. Impairment of F1FO oligomer formation by deletion of its subunits e/g (Su e/g) causes CJ diameter enlargement and reduction of cristae tip numbers and promotes cristae branching. Fcj1 and Su e/g genetically interact. We propose a model in which the antagonism between Fcj1 and Su e/g locally modulates the F1FO oligomeric state, thereby controlling membrane curvature of cristae to generate CJs and cristae tips

Emergency percutaneous needle decompression for tension pneumoperitoneum

<p>Abstract</p> <p>Background</p> <p>Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic.</p> <p>Methods</p> <p>This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension.</p> <p>Results</p> <p>Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs), between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs). Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion), bridging the time to the start of the operation.</p> <p>Conclusions</p> <p>Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no definitive treatment, only a method to bridge the time gap to definitive surgical repair.</p

Clinical and virological characteristics of hospitalised COVID-19 patients in a German tertiary care centre during the first wave of the SARS-CoV-2 pandemic: a prospective observational study

Purpose: Adequate patient allocation is pivotal for optimal resource management in strained healthcare systems, and requires detailed knowledge of clinical and virological disease trajectories. The purpose of this work was to identify risk factors associated with need for invasive mechanical ventilation (IMV), to analyse viral kinetics in patients with and without IMV and to provide a comprehensive description of clinical course. Methods: A cohort of 168 hospitalised adult COVID-19 patients enrolled in a prospective observational study at a large European tertiary care centre was analysed. Results: Forty-four per cent (71/161) of patients required invasive mechanical ventilation (IMV). Shorter duration of symptoms before admission (aOR 1.22 per day less, 95% CI 1.10-1.37, p < 0.01) and history of hypertension (aOR 5.55, 95% CI 2.00-16.82, p < 0.01) were associated with need for IMV. Patients on IMV had higher maximal concentrations, slower decline rates, and longer shedding of SARS-CoV-2 than non-IMV patients (33 days, IQR 26-46.75, vs 18 days, IQR 16-46.75, respectively, p < 0.01). Median duration of hospitalisation was 9 days (IQR 6-15.5) for non-IMV and 49.5 days (IQR 36.8-82.5) for IMV patients. Conclusions: Our results indicate a short duration of symptoms before admission as a risk factor for severe disease that merits further investigation and different viral load kinetics in severely affected patients. Median duration of hospitalisation of IMV patients was longer than described for acute respiratory distress syndrome unrelated to COVID-19

Tree surface temperature in an urban environment

Trees are essential in a dense urban environment not only because of their aesthetic value, but also for their cooling effect during hot periods, which impacts directly on the local microclimate. However, certain trees cope better with high urban temperatures than others. Here, we report tree crown temperatures of 10 common tree species frequently planted in Central European cities (in part, supplemented with stomatal conductance data, gs). Parts of the city of Basel, Switzerland (7°410E/47°340N) were scanned from a helicopter using a high-resolution thermal camera. A histogram of the composite image shows peaks at 18 °C (water), 26 °C (vegetation), 37 °C (streets) and a less obvious one at 45 °C (roofs). At an ambient temperature of c. 25 °C, tree crown temperatures ranged from c. 24 °C (Aesculus hippocastanum trees located in a park) to 29 °C in Acer platanoides trees, located in a street. Trees in parks were significantly cooler (c. 26 °C) than trees surrounded by sealed ground (c. 27 °C). The only coniferous species, Pinus sylvestris did not vary in temperaturewith location (park or street) and exhibited foliage temperature close to air temperature. Generally, small-leaved trees remained cooler than large-leaved trees. Stomatal conductance data collected during similar weather conditions suggest that there was no bias in crown temperatures due to locally different water supply between trees. Although the highest leaf temperatures of individuals of A. platanoides reached over 5 K leaf-to-air temperature difference (dT(L-A)), we do not expect temperature stress to occur in these conditions. In order to estimate possible effects of future temperature extremeson dT(L-A),we evaluated the leaf energy balance fora range of stomatal responses and air temperatures, using leaf size, wind speed and the measured species-specific leaf boundary layer resistance. At an ambient temperature of 40 °C, View the MathML source ranged from 2 to 5 K when gs was assumed to drop linearly to 50% of its maximum value. When gs was compromised further (20% of species-specific maxima), the difference in View the MathML source between species became larger with rising ambient temperature (range 4–10 K). Those species with the lowest leaf temperatures at 25 °C were not necessarily coolest at 40 °C. Species-specific differences in View the MathML source under extreme temperatures as shown here may be useful for urban tree planning in order to optimise management cost and human comfort. Untersuchungsgebiet Base

Crystallization and preliminary crystallographic data of purple acid phosphatase from red kidney bean

Purple acid phosphatase from red kidney bean has been crystallized from ammonium sulfate solutions in the pH range from 3·5 to 5·5. The crystal form is tetragonal bipyramidal and the largest crystals grew up to 2·0 mm long. Systematic absences indicate one of the enantiomorphic space groups P41212 (92) or P43212 (96) with cell dimensions a = b = 104·1(1)Åandc = 308·7(2)Å. The asymmetric unit contains one dimer with Mr of 110,700, determined by ultraviolet-laser desorption mass spectrometry. The crystals, with a salt-free density of 1·12 g/cm3 and a water content of 67%, diffract to 3·5 Å

COVID-19 pandemic and families' utilization of well-child clinics and pediatric practices attendance in Germany

Objective!#!The COVID-19 pandemic and the measures implemented to stop the pandemic had a broad impact on our daily lives. Besides work and social life, health care is affected on many levels. In particular, there is concern that attendance in health care programs will drop or hospital admissions will be delayed due to COVID-19-related anxieties, especially in children. Therefore, we compared the number of weekly visits to 78 German pediatric institutions between 2019 and 2020.!##!Results!#!We found no significant differences during the first 10 weeks of the year. However, and importantly, from April, the weekly number of visits was more than 35% lower in 2020 than in 2019 (p = 0.005). In conclusion, the COVID-19 pandemic seems to relate to families´ utilization of outpatient well-child clinics and pediatric practice attendance in Germany