Der Vorderabschnitt des Auges in spektraler optischer Kohärenztomographie

Die optische Kohärenztomographie (OCT) ist eine interferometrische Technologie, welche die Bildgebung von biologischem Gewebe ermöglicht. Es gibt zwei Arten von OCT, welche auf unterschiedlichen Interferenz-Effekten beruhen. In Spectral Domain (SD) OCT, der schnelleren und sensitiveren Variante, erhält man die Tiefeninformation rückstreuender Objektschichten durch eine Fouriertransformation des spektralen Interferogramms. Ein Nachteil von SD-OCT ist der begrenzte Tiefenbereich, der durch die begrenzte spektrale Auflösung des Spektrometers verursacht wird. Weiters führt die Fouriertransformation des gemessenen reellen spektralen Interferogramms zu charakteristischen Spiegelungsartefakten, die in einer Halbierung des Tiefenbereichs resultieren. Dadurch ist der optische Tiefenbereich herkömmlicher SD-OCT-Systeme auf ~3 mm beschränkt. Eine Anwendung von SD-OCT in der Augenheilkunde ist die Bildgebung des vorderen Augenabschnitts, dem Bereich zwischen Hornhaut und Linse. Wegen des limitierten Tiefenbereichs kann jedoch nur ein Teil des Vorderabschnitts abgebildet werden. Um den gesamten Vorderabschnitt zu erfassen, wurde ein SD-OCT-System mit erweitertem Tiefenbereich aufgebaut. Durch ein adaptiertes Spektrometer-Design wurde die spektrale Auflösung erhöht, was zu einem höheren intrinsischen Tiefenbereich führte. Weiters wurde der spektrale Datensatz mit einer Phasenmodulation versehen, woraus das komplexe spektrale Interferogramm durch eine analytische Erweiterung rekonstruiert werden konnte. Dadurch konnte der optische Tiefenbereich auf ~14 mm erhöht werden. Die Funktion des Systems wurde durch 2D- und 3D-Messungen des gesamten vorderen Augenabschnitts gesunder menschlicher Augen in vivo getestet.Optical coherence tomography (OCT) is an interferometric technology that enables the imaging of biological tissues. There are two kinds of OCT which are based on different interference effects. In spectral domain (SD) OCT, which is faster and more sensitive, the depth information of backscattering sample layers is retrieved by Fourier transform of the spectral interferogram. A drawback of SD-OCT is the limited depth range, which is caused by the limited spectral resolution of the spectrometer. Furthermore, the Fourier transform of the measured real-valued spectral interferogram leads to characteristic mirror artifacts which result in a bisection of the depth range. Therefore, the optical depth range of conventional SD-OCT systems is limited to ~3 mm. An ophthalmologic application of SD-OCT is imaging of the anterior eye segment, the region between the cornea and the lens. Due to the limited depth range, only a part of the anterior segment can be covered. To image the whole anterior segment, a system with an extended depth range was developed. The spectral resolution was improved by an adapted spectrometer design which led to a higher intrinsic depth range. Furthermore, the spectral data set was modified with a phase modulation to reconstruct the complex spectral interferogram by an analytic extension. Thereby, the optical depth range was extended to ~14 mm. The system performance was tested by 2D- and 3D-measurements of the whole anterior eye segment on healthy human eyes in vivo

Stability of Drugs Stored in Helicopters for Use by Emergency Medical Services: A Prospective Observational Study.

STUDY OBJECTIVE Drugs stored in rescue helicopters may be subject to extreme environmental conditions. The aim of this study was to measure whether drugs stored under the real-life conditions of a Swiss helicopter emergency medical service (HEMS) would retain their potency over the course of 1 year. METHODS A prospective, longitudinal study measuring the temperature exposure and concentration of drugs stored on 2 rescue helicopters in Switzerland over 1 year. The study drugs included epinephrine, norepinephrine, amiodarone, midazolam, fentanyl, naloxone, rocuronium, etomidate, and ketamine. Temperatures were measured inside the medication storage bags and the crew cabins at 10-minute intervals. Drug stability was measured on a monthly basis over the course of 12 months using high-performance liquid chromatography. The medications were considered stable at a minimum remaining drug concentration of 90% of the label claim. RESULTS Temperatures ranged from -1.2 °C to 38.1 °C (29.84 °F to 100.58 °F) inside the drug storage bags. Of all the temperature measurements inside the drug storage bags, 37% lay outside the recommended storage conditions. All drugs maintained a concentration above 90% of the label claim. The observation periods for rocuronium and etomidate were shortened to 7 months because of a supply shortage of reference samples. CONCLUSION Drugs stored under the real-life conditions of Swiss HEMS are subjected to temperatures outside the manufacturer's approved storage requirements. Despite this, all drugs stored under these conditions remained stable throughout our study. Real-life stability testing could be a way to extend drug exchange intervals

D,L-Lysine-Acetylsalicylate + Glycine (LASAG) Reduces SARS-CoV-2 Replication and Shows an Additive Effect with Remdesivir

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the coronavirus disease-19 (COVID-19) is still challenging healthcare systems and societies worldwide. While vaccines are available, therapeutic strategies are developing and need to be adapted to each patient. Many clinical approaches focus on the repurposing of approved therapeutics against other diseases. However, the efficacy of these compounds on viral infection or even harmful secondary effects in the context of SARS-CoV-2 infection are sparsely investigated. Similarly, adverse effects of commonly used therapeutics against lifestyle diseases have not been studied in detail. Using mono cell culture systems and a more complex chip model, we investigated the effects of the acetylsalicylic acid (ASA) salt D,L-lysine-acetylsalicylate + glycine (LASAG) on SARS-CoV-2 infection in vitro. ASA is commonly known as Aspirin ® and is one of the most frequently used medications worldwide. Our data indicate an inhibitory effect of LASAG on SARS-CoV-2 replication and SARS-CoV-2-induced expression of pro-inflammatory cytokines and coagulation factors. Remarkably, our data point to an additive effect of the combination of LASAG and the antiviral acting drug remdesivir on SARS-CoV-2 replication in vitro

BRCA1 mislocalization leads to aberrant DNA damage response in heterozygous ABRAXAS1 mutation carrier cells

Peer reviewe

Peroxisomal alterations in Alzheimer’s disease

In Alzheimer’s disease (AD), lipid alterations are present early during disease progression. As some of these alterations point towards a peroxisomal dysfunction, we investigated peroxisomes in human postmortem brains obtained from the cohort-based, longitudinal Vienna-Transdanube Aging (VITA) study. Based on the neuropathological Braak staging for AD on one hemisphere, the patients were grouped into three cohorts of increasing severity (stages I–II, III–IV, and V–VI, respectively). Lipid analyses of cortical regions from the other hemisphere revealed accumulation of C22:0 and very long-chain fatty acids (VLCFA, C24:0 and C26:0), all substrates for peroxisomal β-oxidation, in cases with stages V–VI pathology compared with those modestly affected (stages I–II). Conversely, the level of plasmalogens, which need intact peroxisomes for their biosynthesis, was decreased in severely affected tissues, in agreement with a peroxisomal dysfunction. In addition, the peroxisomal volume density was increased in the soma of neurons in gyrus frontalis at advanced AD stages. Confocal laser microscopy demonstrated a loss of peroxisomes in neuronal processes with abnormally phosphorylated tau protein, implicating impaired trafficking as the cause of altered peroxisomal distribution. Besides the original Braak staging, the study design allowed a direct correlation between the biochemical findings and the amount of neurofibrillary tangles (NFT) and neuritic plaques, quantified in adjacent tissue sections. Interestingly, the decrease in plasmalogens and the increase in VLCFA and peroxisomal volume density in neuronal somata all showed a stronger association with NFT than with neuritic plaques. These results indicate substantial peroxisome-related alterations in AD, which may contribute to the progression of AD pathology

Guidelines and Recommendations on Yeast Cell Death Nomenclature

Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cellular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing. Here, we propose unified criteria for the definition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death routines that are relevant for the biology of (at least some species of) yeast. As this area of investigation advances rapidly, changes and extensions to this set of recommendations will be implemented in the years to come. Nonetheless, we strongly encourage the authors, reviewers and editors of scientific articles to adopt these collective standards in order to establish an accurate framework for yeast cell death research and, ultimately, to accelerate the progress of this vibrant field of research

Guidelines and recommendations on yeast cell death nomenclature

Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cel-lular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing. Here, we propose unified criteria for the defi-nition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differ-ential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death rou-tines that are relevant for the biology of (at least some species of) yeast. As this area of investigation advances rapidly, changes and extensions to this set of recommendations will be implemented in the years to come. Nonetheless, we strongly encourage the au-thors, reviewers and editors of scientific articles to adopt these collective standards in order to establish an accurate framework for yeast cell death research and, ultimately, to accelerate the pro-gress of this vibrant field of research

Keramik aus Numantia (Prov. Soria) im Akademischen Kunstmuseum Bonn

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