Improving the visualization of cryo-EM density reconstructions.

Cryo-electron microscopy yields 3D density maps of macromolecules from single-particle images, tomograms, or 2D crystals. An optimal visualization of the density map is important for its proper interpretation. We have developed a method to improve the visualization of density maps by using general statistical information about proteins for the sharpening process. In particular, the packing density of atoms is highly similar between different proteins, which allows for building a pseudo-atomic model to approximate the true mass distribution. From this model the radial structure factor and density value histogram are estimated and applied as constraints to the 3D reconstruction in reciprocal- and real-space, respectively. Interestingly, similar improvements are obtained when using the correct radial structure factor and density value histogram from a crystal structure. Thus, the estimated pseudo-atomic model yields a sufficiently accurate mass distribution to optimally sharpen a density map.

Movement planning and attentional control of visuospatial working memory: evidence from a grasp-to-place task.

In this study, we have investigated the influence of available attentional resources on the dual-task costs of implementing a new action plan and the influence of movement planning on the transfer of information into visuospatial working memory. To approach these two questions, we have used a motor-memory dual-task design in which participants grasped a sphere and planned a placing movement toward a left or right target according to a directional arrow. Subsequently, they encoded a centrally presented memory stimulus (4 × 4 symbol matrix). While maintaining the information in working memory, a visual stay/change cue (presented on the left, center or right) either confirmed or reversed the planned movement direction. That is, participants had to execute either the prepared or the re-planned movement and finally reported the symbols at leisure. The results show that both, shifts of spatial attention required to process the incongruent stay/change cues and movement re-planning, constitute processing bottlenecks as they both reduced visuospatial working memory performance. Importantly, the spatial attention shifts and movement re-planning appeared to be independent of each other. Further, we found that the initial preparation of the placing movement influenced the report pattern of the central working memory stimulus. Preparing a leftward movement resulted in better memory performance for the left stimulus side, while the preparation of a rightward movement resulted in better memory performance for the right stimulus side. Hence, movement planning influenced the transfer of information into the capacity-limited working memory store. Therefore, our results suggest complex interactions in that the processes involved in movement planning, spatial attention and visuospatial working memory are functionally correlated but not linked in a mandatory fashion.

Safety of Novel Protein Sources (Insects, Microalgae, Seaweed, Duckweed, and Rapeseed) and Legislative Aspects for Their Application in Food and Feed Production.

Novel protein sources (like insects, algae, duckweed, and rapeseed) are expected to enter the European feed and food market as replacers for animal-derived proteins. However, food safety aspects of these novel protein sources are not well-known. The aim of this article is to review the state of the art on the safety of major novel protein sources for feed and food production, in particular insects, algae (microalgae and seaweed), duckweed, and rapeseed. Potential hazards for these protein sources are described and EU legislative requirements as regard to food and feed safety are explained. Potential hazards may include a range of contaminants, like heavy metals, mycotoxins, pesticide residues, as well as pathogens. Some safety aspects of novel protein sources are intrinsic to the product, but many potential hazards can also be due to production methods and processing conditions. These aspects should be considered in advance during product development. European law is unclear on several issues regarding the use of novel protein sources in food and feed products. For food product applications, the most important question for food producers is whether or not the product is considered a novel food. One of the major unclarities for feed applications is whether or not products with insects are considered animal-derived products or not. Due to the unclarities in European law, it is not always clear which Regulation and maximum levels for contaminants apply. For market introduction, European legislation should be adjusted and clarified.

[Coronavirus: from common cold to severe pulmonary failure]. / Coronaviren: von der banalen Erkältung zum schweren Lungenversagen: Chronologie einer Pandemie.

In December 2019 a new human coronavirus emerged in Wuhan, China, which is known as SARS-CoV­2. The clinical course of the disease known as coronavirus disease 2019 (COVID-19) ranges from mild respiratory symptoms to severe lung failure. The virus is currently rapidly spreading around the world and pushing health systems to the limits of their capacity due to the exponential increase in the number of cases. The origin of SARS-CoV­2 lies in the bat coronavirus pool and has now emerged in the human population due to interspecies transmission. Molecular diagnostic methods have been established in a very short time and a number of clinical studies on the effectiveness of different antiviral drugs are ongoing. The development of a vaccine using different approaches is also under investigation.Considering the high number of cases and mortality rates of up to 9% there is an urgent need for action. This article summarizes the current state of knowledge on human coronaviruses with a strong focus on the current data on SARS-CoV­2. Due to the daily changing level of knowledge, the article reflects the status up to 21 March 2020.

Fibronectin in the developing sea urchin embryo.

The presence of fibronectin in developing sea urchin embryos was studied uing immunofluorescence staining. The fluorescence pattern indicates that fibronectin is found on the cell surfaces and between cells in the blastula and gastrula stages, indicating that it plays a role in cell adhesion. Its presence on invaginating cells also suggests its involvement in morphogenesis during early development.

Protein synthesis in micromeres of the sea urchin egg.

A method was developed for isolating large quantities of micromeres from the 16-cell stage of the sea urchin, and measurements were made of their ability to incorporate C(14)-L-valine into protein as compared with that of a mixed suspension of micromeres, mesomeres, and macromeres. Per cell, the rate of incorporation was considerably less for the micromeres than for the suspension of mixed cells. Per unit volume, however, the two types of suspensions showed no significant differences.

A Phase II Study of Pembrolizumab in EGFR-Mutant, PD-L1+, Tyrosine Kinase Inhibitor Naïve Patients With Advanced NSCLC.

BACKGROUND: Despite the significant antitumor activity of pembrolizumab in NSCLC, clinical benefit has been less frequently observed in patients whose tumors harbor EGFR mutations compared to EGFR wild-type patients. Our single-center experience on the KEYNOTE-001 trial suggested that pembrolizumab-treated EGFR-mutant patients, who were tyrosine kinase inhibitor (TKI) naïve, had superior clinical outcomes to those previously treated with a TKI. As TKI naïve EGFR-mutants have generally been excluded from pembrolizumab studies, data to guide treatment decisions in this patient population is lacking, particularly in patients with programmed death ligand 1 (PD-L1) expression ≥50%. METHODS: We conducted a phase II trial (NCT02879994) of pembrolizumab in TKI naive patients with EGFR mutation-positive, advanced NSCLC and PD-L1-positive (≥1%, 22C3 antibody) tumors. Pembrolizumab was administered 200 mg every 3 weeks. The primary endpoint was objective response rate. Secondary endpoints included safety of pembrolizumab, additional pembrolizumab efficacy endpoints, and efficacy and safety of an EGFR TKI after pembrolizumab. RESULTS: Enrollment was ceased due to lack of efficacy after 11 of 25 planned patients were treated. Eighty-two percent of trial patients were treatment naïve, 64% had sensitizing EGFR mutations, and 73% had PD-L1 expression ≥50%. Only 1 patient had an objective response (9%), but repeat analysis of this patient's tumor definitively showed the original report of an EGFR mutation to be erroneous. Observed treatment-related adverse events were similar to prior experience with pembrolizumab, but two deaths within 6 months of enrollment, including one attributed to pneumonitis, were of concern. CONCLUSIONS: Pembrolizumab's lack of efficacy in TKI naïve, PD-L1+, EGFR-mutant patients with advanced NSCLC, including those with PD-L1 expression ≥50%, suggests that it is not an appropriate therapeutic choice in this setting.

Two independent chromosomal rearrangements, a very small (550 kb) duplication of the 7q subtelomeric region and an atypical 17q11.2 (NF1) microdeletion, in a girl with neurofibromatosis.

Most patients with neurofibromatosis (NF1) are endowed with heterozygous mutations in the NF1 gene. Approximately 5% show an interstitial deletion of chromosome 17q11.2 (including NF1) and in most cases also a more severe phenotype. Here we report on a 7-year-old girl with classical NF1 signs, and in addition mild overgrowth (97th percentile), relatively low OFC (10th-25th percentile), facial dysmorphy, hoarse voice, and developmental delay. FISH analysis revealed a 17q11.2 microdeletion as well as an unbalanced 7p;13q translocation leading to trisomy of the 7q36.3 subtelomeric region. The patient's mother and grandmother who were phenotypically normal carried the same unbalanced translocation. The 17q11.2 microdeletion had arisen de novo. Array comparative genomic hybridization (CGH) demonstrated gain of a 550-kb segment from 7qter and loss of 2.5 Mb from 17q11.2 (an atypical NF1 microdeletion). We conclude that the patient's phenotype is caused by the atypical NF1 deletion, whereas 7q36.3 trisomy represents a subtelomeric copy number variation without phenotypic consequences. To our knowledge this is the first report that a duplication of the subtelomeric region of chromosome 7q containing functional genes (FAM62B, WDR60, and VIPR2) can be tolerated without phenotypic consequences. The 17q11.2 microdeletion (containing nine more genes than the common NF1 microdeletions) and the 7qter duplication were not accompanied by unexpected clinical features. Most likely the 7qter trisomy and the 17q11.2 microdeletion coincide by chance in our patient.

Reconciling agriculture, carbon and biodiversity in a savannah transformation frontier.

Rapidly rising populations and likely increases in incomes in sub-Saharan Africa make tens of millions of hectares of cropland expansion nearly inevitable, even with large increases in crop yields. Much of that expansion is likely to occur in higher rainfall savannas, with substantial costs to biodiversity and carbon storage. Zambia presents an acute example of this challenge, with an expected tripling of population by 2050, good potential to expand maize and soya bean production, and large areas of relatively undisturbed miombo woodland and associated habitat types of high biodiversity value. Here, we present a new model designed to explore the potential for targeting agricultural expansion in ways that achieve quantitatively optimal trade-offs between competing economic and environmental objectives: total converted land area (the reciprocal of potential yield); carbon loss, biodiversity loss and transportation costs. To allow different interests to find potential compromises, users can apply varying weights to examine the effects of their subjective preferences on the spatial allocation of new cropland and its costs. We find that small compromises from the objective to convert the highest yielding areas permit large savings in transportation costs, and the carbon and biodiversity impacts resulting from savannah conversion. For example, transferring just 30% of weight from a yield-maximizing objective equally between carbon and biodiversity protection objectives would increase total cropland area by just 2.7%, but result in avoided costs of 27-47% for carbon, biodiversity and transportation. Compromise solutions tend to focus agricultural expansion along existing transportation corridors and in already disturbed areas. Used appropriately, this type of model could help countries find agricultural expansion alternatives and related infrastructure and land use policies that help achieve production targets while helping to conserve Africa's rapidly transforming savannahs.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'.

Menstrual cycle dependent right-to-left shunting: a single-blinded transcranial Doppler sonography study.

BACKGROUND AND PURPOSE: Menstruation has been described as risk factor for neurological decompression sickness in divers. In considering this for paradoxical gas embolism, we hypothesized that there may be a link between cycle-dependent hormonal changes and the manifestation of a right-to-left shunt (RLS). METHODS: 40 women with a regular cycle of 28 days underwent transcranial Doppler sonography examinations (TCD) on day 1 and on day 15 of the menstrual cycle. Cerebral high intensity transient signs (HITS) proved a RLS. RESULTS: We found a 25% RLS incidence consistent with the literature. In 7 of 10 shunt-positive women it was detected mainly or exclusively on day 15. This difference in PFO detection rate is statistically significant (p = 0.031), indicating more RLS during the peri-ovulatory period. CONCLUSIONS: Our results do not support menstruation as a risk factor for neurological decompression sickness. The peri-ovulatory estrogen peak, which leads to systemic vasodilation, may explain our data. Factors that increase the risk for developing a RLS and thereby paradoxical embolism should be avoided, perhaps including diving during the peri-ovulatory period of the menstrual cycle. Furthermore, contrast PFO testing in fertile females may be most sensitive if conducted mid-cycle.

A prototype transduction tag system (delta LNGFR/NGF) for noninvasive clinical gene therapy monitoring.

The dramatic expansion of clinical gene therapy trials requires the development of noninvasive clinical monitoring procedures, which provide information about expression levels, expression kinetics, and spatial distribution of transduced therapeutic genes. With the development of such procedures, invasive sampling of tissue probes from patients potentially could be reduced significantly. In this study, an experimental platform for the rational design and in vitro testing of suitable receptor-ligand couples as components of future transduction tag systems for noninvasive gene therapy monitoring applications was developed. Initially, the feasibility of the delta LNGFR/nerve growth factor (NGF) transduction tag system was investigated; this system employs a mutated version of the low-affinity nerve growth factor receptor (p75mut or delta LNGFR) lacking the entire cytoplasmic domain. Specific binding of 125I-radiolabeled NGF was demonstrated for two stable delta LNGFR-transduced cell lines, but not for delta LNGFR-negative parental control cell lines. An additional binding analysis performed in a MicroImager directly confirmed binding of radiolabeled ligands (125I-NGF, 125I-anti-p75 monoclonal antibody) to the p75mut expressed on intact target cells, but not on control cells. Subsequent binding studies employing NGF radiolabeled with the positron-emitting isotope 124I demonstrated a specific binding for LNGFR+ PC12 cells. Consequently, the first in vitro proof of a transduction tag approach based on the specificity of the 124I-NGF/LNGFR interaction was provided, which opens up the possibility for future noninvasive positron emission tomography monitoring in clinical gene therapy trials.

Cryptococcal meningitis in systemic lupus erythematosus.

Two cases of cryptococcal meningitis occurring in patients with systemic lupus erythematosus (SLE) are presented, and 24 additional cases from the literature are reviewed. The insidious onset of this infrequent complication is emphasized. The nonspecific neurological findings associated with this infection are often mistakenly diagnosed as a central nervous system manifestation of SLE. Earlier diagnosis and effective antifungal therapy have improved the prognosis of cryptococcal meningitis in SLE patients in recent years. Strategies for the treatment of patients with this complication are discussed.

MRI study of Baló's concentric sclerosis before and after immunosuppressive therapy.

An intra vitam diagnosis of Baló's concentric sclerosis in a 39-year-old male is described. To our knowledge this is the first reported case of ante-mortem diagnosis based solely on magnetic resonance imaging (MRI) findings. MRI showed features unique to this process. After high-dose intravenous therapy with prednisone, the clinical symptoms improved, and MRI showed marked changes of the concentric lesions.

Extracellular matrix of sea urchin and other marine invertebrate embryos.

The extracellular matrix surrounding the sea urchin embryo (outer ECM) contains fibers and granules of various sizes which are organized in recognizable patterns as shown by ultrastructural studies, particularly stereoimaging techniques. The use of the ruthenium red method for retaining and staining the ECM, with modifications of the Luft (Anatomical Record 171:347-368, 1971) method for invertebrate embryos, allows for the clarification of certain structures, particularly fiber compaction in the interzonal region, and microvillus-associated bodies. The inner ECM in the sea urchin embryo includes the basal lamina and blastocoel matrix. Stereoimages show that the fibers which are loosely distributed in the blastocoel matrix become compacted around the periphery of the blastocoel to form the basal lamina. The ruthenium red method was also used on a number of marine invertebrate embryos and larvae, representing different phyla, to facilitate comparisons between their surface coats. The similarities observed in the specimens shown suggest that ECMs are widely found on marine invertebrate eggs, embryos, and larvae, and that they resemble vertebrate ECMs and may, therefore, have similar functions.

Quantification of the local heartwall motion by magnetic resonance myocardial tagging.

Sophisticated magnetic resonance tagging techniques provide powerful tools for the non-invasive assessment of the local heartwall motion towards a deeper fundamental understanding of local heart function. For the extraction of motion data from the time series of magnetic resonance tagged images and for the visualization of the local heartwall motion a new image analysis procedure has been developed. New parameters have been derived which allows quantification of the motion patterns and are highly sensitive to any changes in these patterns. The new procedure has been applied for heart motion analysis in healthy volunteers and in patient collectives with different heart diseases. The achieved results are summarized and discussed.

[Extensive aneurysm of the internal carotid artery with free floating round thrombus]. / Ausgedehntes Aneurysma der Arteria carotis interna mit frei flottierendem Kugelthrombus.

A large asymptomatic aneurysm of the internal carotid artery containing a free floating thrombus was detected in a 90-year-old woman. The alteration was documented by duplex sonography of the extracranial carotid arteries. At a second examination 4 days later the thrombus was observed to be fixed to the dorsal and distal aneurysm wall. With regard to the age and reduced general state of health of the patient, invasive diagnostic examinations and reconstructive surgery were not indicated and the patient was released in a good condition.

Keeping patients with arthritis out of the hospital.

The use of nonsteroidal anti-inflammatory drugs in the treatment of osteoarthritis and rheumatoid arthritis is frequently associated with gastrointestinal complications, particularly gastric bleeding. The author outlines a strategy for avoiding these complications, thereby decreasing the risk for hospitalization and/or death.

Selling accounts receivable can improve cash flow.

New financing programs especially geared to accounts receivable allow healthcare organizations to convert these assets into cash literally overnight and at costs below the prime interest rate. Certain pooled versions of the financing strategy include non-recourse features that guard against sharing bad debts among the participants. These pooled programs generally allow hospitals to continue managing and billing their own accounts.

The functional role of working memory in the (re-)planning and execution of grasping movements.

Three experiments were conducted to dissociate movement planning costs and movement execution costs in working memory (WM). The aim of the study was to clarify what kind of WM processes (verbal, spatial, or both) are recruited during movement planning and movement execution. Therefore, a WM task (verbal and spatial versions) was combined with a high-precision manual action. Participants initially planned a placing movement toward 1 of 2 targets, subsequently encoded verbal or spatial information in WM, and then executed the movement during the retention phase. We tested the impact of movement execution on memory performance (Experiment 1), the role of WM task difficulty as a moderating variable in motor-memory interactions (Experiment 2), and the impact of implementing a new motor plan during memory retention (Experiment 3). Our results show that movement execution disrupted spatial more than verbal memory (Experiment 1) and that this domain-specific interference pattern was independent of WM task difficulty (Experiment 2). Hence, the results of Experiments 1 and 2 demonstrate that executing a prepared movement recruits domain-specific visuospatial memory resources. Experiment 3 involved trials that required the implementation of a new motor plan. The additional planning requirement during the retention phase reduced performance in both WM tasks in equal measure beyond the relative movement execution costs observed in Experiments 1 and 2. These results provide evidence for distinct roles of WM in manual actions, with action execution requiring principally modality-specific capacities and (re-)planning engaging modality-general WM resources.

A novel laboratory set-up for investigating surface and interface reactions during short term annealing cycles at high temperatures.

High temperature oxidation is an important research discipline that covers many topics in steel manufacture and modern energy research. To account for the need of adjusting accurate processing conditions, recent developments of the high temperature laboratory setup at the Max-Planck-Institut für Eisenforschung GmbH will be presented. The experimental assembly has been optimized to investigate surface and interface reactions at elevated temperatures in low oxygen activity gases, covering a large field of experimental possibilities. Many efforts have been taken to enable an accurate control and in situ monitoring of process conditions such as gas flow, gas composition, impurity content, and mass change of the sample.