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An accelerating Brewer-Dobson circulation (BDC) is a robust signal of climate change in model predictions but has been questioned by trace gas observations. We analyze stratospheric mean age of air and the full age spectrum as measures for the BDC and its trend. Age of air is calculated with the Chemical Lagrangian Model of the Stratosphere (CLaMS) driven by ERA-Interim, JRA-55 and MERRA-2 reanalysis data to assess the robustness of the representation of the BDC in current generation meteorological reanalyses. We find that climatological mean age significantly depends on the reanalysis, with JRA-55 showing the youngest and MERRA-2 the oldest mean age. Consideration of the age spectrum indicates that the older age for MERRA-2 is related to a stronger spectrum tail, likely related to weaker tropical upwelling and stronger recirculation. Seasonality of stratospheric transport is robustly represented in reanalyses, with similar mean age variations and age spectrum peaks. Long-term changes over 1989–2015 turn out to be similar for the reanalyses with mainly decreasing mean age accompanied by a shift of the age spectrum peak towards shorter transit times, resembling the forced response in climate model simulations to increasing greenhouse gas concentrations. For the shorter periods 1989–2001 and 2002–2015 age of air changes are less robust. Only ERA-Interim shows the hemispheric dipole pattern in age changes during 2002–2015 as viewed by recent satellite observations. Consequently, the representation of decadal variability of the BDC in current generation reanalyses appears less robust and a major uncertainty of modelling the BDC.
SARS-CoV-2 and stroke characteristics: a report from the Multinational COVID-19 Stroke Study Group
(2020)
Background: Stroke is reported as a consequence of SARS-CoV-2 infection. However, there is a lack of regarding comprehensive stroke phenotype and characteristics
Methods: We conducted a multinational observational study on features of consecutive acute ischemic stroke (AIS), intracranial hemorrhage (ICH), and cerebral venous or sinus thrombosis (CVST) among SARS-CoV-2 infected patients. We further investigated the association of demographics, clinical data, geographical regions, and countries’ health expenditure among AIS patients with the risk of large vessel occlusion (LVO), stroke severity as measured by National Institute of Health stroke scale (NIHSS), and stroke subtype as measured by the TOAST criteria. Additionally, we applied unsupervised machine learning algorithms to uncover possible similarities among stroke patients.
Results: Among the 136 tertiary centers of 32 countries who participated in this study, 71 centers from 17 countries had at least one eligible stroke patient. Out of 432 patients included, 323(74.8%) had AIS, 91(21.1%) ICH, and 18(4.2%) CVST. Among 23 patients with subarachnoid hemorrhage, 16(69.5%) had no evidence of aneurysm. A total of 183(42.4%) patients were women, 104(24.1%) patients were younger than 55 years, and 105(24.4%) patients had no identifiable vascular risk factors. Among 380 patients who had known interval onset of the SARS-CoV-2 and stroke, 144(37.8%) presented to the hospital with chief complaints of stroke-related symptoms, with asymptomatic or undiagnosed SARS-CoV-2 infection. Among AIS patients 44.5% had LVO; 10% had small artery occlusion according to the TOAST criteria. We observed a lower median NIHSS (8[3-17], versus 11 [5-17]; p=0.02) and higher rate of mechanical thrombectomy (12.4% versus 2%; p<0.001) in countries with middle to high-health expenditure when compared to countries with lower health expenditure. The unsupervised machine learning identified 4 subgroups, with a relatively large group with no or limited comorbidities.
Conclusions: We observed a relatively high number of young, and asymptomatic SARS-CoV-2 infections among stroke patients. Traditional vascular risk factors were absent among a relatively large cohort of patients. Among hospitalized patients, the stroke severity was lower and rate of mechanical thrombectomy was higher among countries with middle to high-health expenditure.
Dendritic spines are crucial for excitatory synaptic transmission as the size of a spine head correlates with the strength of its synapse. The distribution of spine head sizes follows a lognormal-like distribution with more small spines than large ones. We analysed the impact of synaptic activity and plasticity on the spine size distribution in adult-born hippocampal granule cells from rats with induced homo- and heterosynaptic long-term plasticity in vivo and CA1 pyramidal cells from Munc-13-1-Munc13-2 knockout mice with completely blocked synaptic transmission. Neither induction of extrinsic synaptic plasticity nor the blockage of presynaptic activity degrades the lognormal-like distribution but changes its mean, variance and skewness. The skewed distribution develops early in the life of the neuron. Our findings and their computational modelling support the idea that intrinsic synaptic plasticity is sufficient for the generation, while a combination of intrinsic and extrinsic synaptic plasticity maintains lognormal like distribution of spines.
The TOM complex is the main entry point for precursor proteins into mitochondria. Precursor proteins containing targeting sequences are recognized by the TOM complex and imported into the mitochondria. We have determined the structure of the TOM core complex from Neurospora crassa by single-particle cryoEM at 3.3 Å resolution, showing its interaction with a bound presequence at 4 Å resolution, and of the TOM holo complex including the Tom20 receptor at 6-7 Å resolution. TOM is a transmembrane complex consisting of two β-barrels, three receptor subunits and three short transmembrane subunits. Tom20 has a transmembrane helix and a receptor domain on the cytoplasmic side. We propose that Tom20 acts as a dynamic gatekeeper, guiding precursor proteins into the pores of the TOM complex. We analyze the interactions of Tom20 with other TOM subunits, present insights into the structure of the TOM holo complex, and suggest a translocation mechanism.
Objectives: To evaluate the predictive value of volumetric bone mineral density (BMD) assessment of the lumbar spine derived from phantomless dual-energy CT (DECT)-based volumetric material decomposition as an indicator for the 2-year occurrence risk of osteoporosis-associated fractures. Methods: L1 of 92 patients (46 men, 46 women; mean age, 64 years, range, 19–103 years) who had undergone third-generation dual-source DECT between 01/2016 and 12/2018 was retrospectively analyzed. For phantomless BMD assessment, dedicated DECT postprocessing software using material decomposition was applied. Digital files of all patients were sighted for 2 years following DECT to obtain the incidence of osteoporotic fractures. Receiver operating characteristic (ROC) analysis was used to calculate cut-off values and logistic regression models were used to determine associations of BMD, sex, and age with the occurrence of osteoporotic fractures. Results: A DECT-derived BMD cut-off of 93.70 mg/cm3 yielded 85.45% sensitivity and 89.19% specificity for the prediction to sustain one or more osteoporosis-associated fractures within 2 years after BMD measurement. DECT-derived BMD was significantly associated with the occurrence of new fractures (odds ratio of 0.8710, 95% CI, 0.091–0.9375, p < .001), indicating a protective effect of increased DECT-derived BMD values. Overall AUC was 0.9373 (CI, 0.867–0.977, p < .001) for the differentiation of patients who sustained osteoporosis-associated fractures within 2 years of BMD assessment. Conclusions: Retrospective DECT-based volumetric BMD assessment can accurately predict the 2-year risk to sustain an osteoporosis-associated fracture in at-risk patients without requiring a calibration phantom. Lower DECT-based BMD values are strongly associated with an increased risk to sustain fragility fractures.
Key Points: Dual-energy CT–derived assessment of bone mineral density can identify patients at risk to sustain osteoporosis-associated fractures with a sensitivity of 85.45% and a specificity of 89.19%. The DECT-derived BMD threshold for identification of at-risk patients lies above the American College of Radiology (ACR) QCT guidelines for the identification of osteoporosis (93.70 mg/cm 3 vs 80 mg/cm 3 ).
System size dependence of multiplicity fluctuations of charged particles produced in nuclear collisions at 158 A GeV was studied in the NA49 CERN experiment. Results indicate a non-monotonic dependence of the scaled variance of the multiplicity distribution with a maximum for semi-peripheral Pb+Pb interactions with number of projectile participants of about 35. This effect is not observed in a string-hadronic model of nuclear collision HIJING.
Highlights
• 153 chemicals of emerging concern detected in complex multi-component mixtures.
• 108 possible mixture risk assessment scenarios were investigated.
• Non-detects, QSARs, and experimental ecotoxicological data were integrated for risk assessment.
• 8 chemicals were the main risk drivers in at least one site across the River Aconcagua basin.
Abstract
Environmental risk assessments strategies that account for the complexity of exposures are needed in order to evaluate the toxic pressure of emerging chemicals, which also provide suggestions for risk mitigation and management, if necessary. Currently, most studies on the co-occurrence and environmental impacts of chemicals of emerging concern (CECs) are conducted in countries of the Global North, leaving massive knowledge gaps in countries of the Global South.
In this study, we implement a multi-scenario risk assessment strategy to improve the assessment of both the exposure and hazard components in the chemical risk assessment process. Our strategy incorporates a systematic consideration and weighting of CECs that were not detected, as well as an evaluation of the uncertainties associated with Quantitative Structure-Activity Relationships (QSARs) predictions for chronic ecotoxicity. Furthermore, we present a novel approach to identifying mixture risk drivers. To expand our knowledge beyond well-studied aquatic ecosystems, we applied this multi-scenario strategy to the River Aconcagua basin of Central Chile. The analysis revealed that the concentrations of CECs exceeded acceptable risk thresholds for selected organism groups and the most vulnerable taxonomic groups. Streams flowing through agricultural areas and sites near the river mouth exhibited the highest risks. Notably, the eight risk drivers among the 153 co-occurring chemicals accounted for 66–92 % of the observed risks in the river basin. Six of them are pesticides and pharmaceuticals, chemical classes known for their high biological activity in specific target organisms.
Purpose: Current systemic treatment of targeted therapies, namely the vascular endothelial growth factor-antibody (VEGF-AB), VEGF receptor tyrosine kinase inhibitor (TKI) and mammalian target of rapamycin (mTOR) inhibitors, have improved progression-free survival and replaced non-specific immunotherapy with cytokines in metastatic renal cell carcinoma (mRCC).
Methods: A panel of experts convened to review currently available phase 3 data for mRCC treatment of approved agents, in addition to available EAU guideline data for a collaborative review as the plurality of substances offers different options of first-, second- and third-line treatment with potential sequencing.
Results: Sunitinib and pazopanib are approved treatments in first-line therapy for patients with favorable- or intermediate-risk clear cell RCC (ccRCC). Temsirolimus has proven benefit over interferon-alfa (IFN-α) in patients with non-clear cell RCC (non-ccRCC). In the second-line treatment TKIs or mTOR inhibitors are treatment choices. Therapy options after TKI failure consist of everolimus and axitinib. Available third-line options consist of everolimus and sorafenib. Recently, nivolumab, a programmed death-1 (PD1) checkpoint inhibitor, improved overall survival benefit compared to everolimus after failure of one or two VEGFR-targeted therapies, which is likely to become the first established checkpoint inhibitor in mRCC. Data for the sequencing of agents remain limited.
Conclusions: Despite the high level of evidence for first and second-line treatment in mRCC, data for third-line therapy are limited. Possible sequences include TKI-mTOR-TKI or TKI–TKI-mTOR with the upcoming checkpoint inhibitors in perspective, which might settle a new standard of care after previous TKI therapy.
(1) Background: Refractory acute graft-versus-host disease (R-aGvHD) remains a leading cause of death after allogeneic stem cell transplantation. Survival rates of 15% after four years are currently achieved; deaths are only in part due to aGvHD itself, but mostly due to adverse effects of R-aGvHD treatment with immunosuppressive agents as these predispose patients to opportunistic infections and loss of graft-versus-leukemia surveillance resulting in relapse. Mesenchymal stromal cells (MSC) from different tissues and those generated by various protocols have been proposed as a remedy for R-aGvHD but the enthusiasm raised by initial reports has not been ubiquitously reproduced.
(2) Methods: We previously reported on a unique MSC product, which was generated from pooled bone marrow mononuclear cells of multiple third-party donors. The products showed dose-to-dose equipotency and greater immunosuppressive capacity than individually expanded MSCs from the same donors. This product, MSC-FFM, has entered clinical routine in Germany where it is licensed with a national hospital exemption authorization. We previously reported satisfying initial clinical outcomes, which we are now updating. The data were collected in our post-approval pharmacovigilance program, i.e., this is not a clinical study and the data is high-level and non-monitored.
(3) Results: Follow-up for 92 recipients of MSC-FFM was reported, 88 with GvHD ≥°III, one-third only steroid-refractory and two-thirds therapy resistant (refractory to steroids plus ≥2 additional lines of treatment). A median of three doses of MSC-FFM was administered without apparent toxicity. Overall response rates were 82% and 81% at the first and last evaluation, respectively. At six months, the estimated overall survival was 64%, while the cumulative incidence of death from underlying disease was 3%.
(4) Conclusions: MSC-FFM promises to be a safe and efficient treatment for severe R-aGvHD.
Vaccination represents one of the fundamentals in the fight against SARS-CoV-2. Myocarditis has been reported as a rare but possible adverse consequence of different vaccines, and its clinical presentation can range from mild symptoms to acute heart failure. We report a case of a 29-year-old man who presented with fever and retrosternal pain after receiving SARS-CoV-2 vaccine. Cardiac magnetic resonance imaging and laboratory data revealed typical findings of acute myocarditis.
Angiotensin II (ANG II), das physiologisch aktivste Produkt des Renin-Angiotensin-Systems (RAS), ist als ein Vasokonstriktor maßgeblich an der Modulation des Blutdrucks beteiligt. Darüber hinaus spielt das Octapeptid eine wichtige Rolle in der Freisetzung von Vasopressin und Hypophysenhormonen und reguliert den Flüssigkeits- und Salzhaushalt. Die Modulation des Blutdrucks sowie die Stimulation der Vasopressinfreisetzung werden über seine AT1-Rezeptoren vermittelt. Viele dieser physiologischen Funktionen zeigen eine klare Tag/Nacht-Variation. Der Nucleus suprachiasmaticus des Hypothalamus (SCN) repräsentiert den zentralen Schrittmacher der circadianen Uhr der Säugertiere und reguliert mitunter den Schlaf/Wach-Zyklus und den circadianen Rhythmus des Blutdrucks. Mit der Entwicklung eines transgen-hypertensiven Rattenstammes [TGR(mREN2)27], der über eine der Herzfrequenz und Aktivität entgegengesetzt phasenverschobene circadiane Rhythmik des Blutdrucks verfügt, konnte eine enge physiologische Beziehung zwischen ANG II und dem SCN aufgezeigt werden. Diese Hypertonie wird durch das zusätzliche und zudem noch übermäßig exprimierte Mäuse-Renin2-Gen im Zirkulations-RAS dieser Ratten verursacht. Die hieraus folgende übermäßige Bereitstellung von Renin im Blutkreislauf führt zu einer erhöhten Konzentration von ANG II im systemischen Kreislauf. Die Funktionswege, die zur phasenverschobenen circadianen Rhythmik des Blutdrucks bei TGR führen sowie die Rolle, die das Octapeptid ANG II generell in der Blutdruckmodulation bei normotensiven und transgen-hypertensiven Tieren spielt, sind noch weitgehend unbekannt. Es wird angenommen, dass das Gehirn-RAS über eine autonome ANG II-Synthese Einfluss auf die Modulation des Blutdrucks ausübt. Ob dieser Einfluss des Gehirn-RAS direkt am zentralen Schrittmacher der circadianen Rhythmik ansetzt und ob und wie sich dieser Einfluss durch das Transgen der TGR verändert, ist ebenfalls nicht bekannt. Um die Wirkung des im Blutkreislauf übermäßig vorhandenen ANG II auf Komponenten des Gehirn-RAS in Hirnarealen vor und hinter der funktionellen Blut/Hirn-Schranke auf zuzeigen, wurden im Verlauf dieser Arbeit der SCN sowie zwei Zirkumventrikularorgane von normotensiven Sprague-Dawley (SDR) und transgen-hypertensiven TGR(mREN2)27 (TGR) Ratten auf die Dichte und Verteilung ihrer AT1-Rezeptoren hin überprüft. Da die physiologische Rolle von ANG II im SCN selbst auch ungeklärt ist und ultrastrukturelle Befunde zur Lokalisation des Octapeptids und seiner AT1-Rezeptoren im SCN bisher nicht verfügbar sind, wurde in dieser Dissertationsarbeit eine immunhistologische Technik entwickelt, mit deren Hilfe sich Immunreaktionen gegen das Octapeptid ANG II und seine AT1-Rezeptoren auf licht- und elektronenmikroskopischer Ebene darstellen lassen. Die hier beschriebenen Befunde machen den Einfluss des Transgens - vermittelt durch die erhöhte ANG II-Konzentration im Blutkreislauf von TGR - auf Veränderungen in Dichte und Verteilung der AT1-Rezeptoren in Hirnarealen vor und hinter der funktionellen Blut/Hirn-Schranke deutlich. AT1-Rezeptoren erscheinen in Hirnarealen mit offenem Kapillarsystem reduziert, im SCN dagegen unverändert und in anderen Regionen mit funktioneller Blut/Hirn-Schranke teilweise erhöht. Lokal begrenzte Veränderungen in der Bereitstellung der AT1-Rezeptoren innerhalb einzelner Kerngebiete hängen maßgeblich von deren topographischer Organisation ab, die bei bisherigen autoradiographischen- und Ligand-Bindungs-Studien jedoch keine Berücksichtigung fand. Die hier vorliegende Arbeit demonstriert erstmalig, dass ANG II im SCN als ein Neurotransmitter und -Modulator fungiert, dessen Effekte über seinen AT1-Rezeptor vermittelt werden. Der Rezeptor vermittelt des Weiteren auch den aktiven - vermutlich bidirektionalen - Transport von ANG II durch die Kapillarendothelien des SCN und ist an der Aufnahme von ANG II (Endozytose) und dessen intrazellulären Transport in einem Hormon/Rezeptor-Komplex in Neuronen, Glia- und Endothelzellen im SCN beteiligt. Die Befunde machen darüber hinaus eine Synthese von ANG II in distinkten Neuronen des SCN wahrscheinlich und deuten an, dass autonom produziertes ANG II im SCN an der Regulation des Blutdrucks und der Freisetzung von Vasopressin beteiligt ist.
n this paper we report on the investigation of baryonic resonance production in proton-proton collisions at the kinetic energies of 1.25 GeV and 3.5 GeV, based on data measured with HADES. Exclusive channels npπ+ and ppπ0 as well as ppe+e− were studied simultaneously in the framework of a one-boson exchange model. The resonance cross sections were determined from the one-pion channels for Δ(1232) and N(1440) (1.25 GeV) as well as further Δ and N* resonances up to 2 GeV/c2 for the 3.5 GeV data. The data at 1.25 GeV energy were also analysed within the framework of the partial wave analysis together with the set of several other measurements at lower energies. The obtained solutions provided the evolution of resonance production with the beam energy, showing a sizeable non-resonant contribution but with still dominating contribution of Δ(1232)P33. In the case of 3.5 GeV data, the study of the ppe+e− channel gave the insight on the Dalitz decays of the baryon resonances and, in particular, on the electromagnetic transition form-factors in the time-like region. We show that the assumption of a constant electromagnetic transition form-factors leads to underestimation of the yield in the dielectron invariant mass spectrum below the vector mesons pole. On the other hand, a comparison with various transport models shows the important role of intermediate ρ production, though with a large model dependency. The exclusive channels analysis done by the HADES collaboration provides new stringent restrictions on the parameterizations used in the models.
his contribution aims to give a basic overview of the latest results regarding the production of resonances in different collision systems. The results were extracted from experimental data collected with HADES that is a multipurpose detector located at the GSI Helmholtzzentrum, Darmstadt. The main points discussed here are: the properties of the strange resonances Λ(1405) and Σ(1385), the role of Δ’s as a source of pions in the final state, the production dynamics reflected in form of differential cross sections, and the role of the ϕ meson as a source for K− particles.
Objectives: To compare dual-energy CT (DECT) and MRI for assessing presence and extent of traumatic bone marrow edema (BME) and fracture line depiction in acute vertebral fractures. Methods: Eighty-eight consecutive patients who underwent dual-source DECT and 3-T MRI of the spine were retrospectively analyzed. Five radiologists assessed all vertebrae for presence and extent of BME and for identification of acute fracture lines on MRI and, after 12 weeks, on DECT series. Additionally, image quality, image noise, and diagnostic confidence for overall diagnosis of acute vertebral fracture were assessed. Quantitative analysis of CT numbers was performed by a sixth radiologist. Two radiologists analyzed MRI and grayscale DECT series to define the reference standard. Results: For assessing BME presence and extent, DECT showed high sensitivity (89% and 84%, respectively) and specificity (98% in both), and similarly high diagnostic confidence compared to MRI (2.30 vs. 2.32; range 0–3) for the detection of BME (p = .72). For evaluating acute fracture lines, MRI achieved high specificity (95%), moderate sensitivity (76%), and a significantly lower diagnostic confidence compared to DECT (2.42 vs. 2.62, range 0–3) (p < .001). A cutoff value of − 0.43 HU provided a sensitivity of 89% and a specificity of 90% for diagnosing BME, with an overall AUC of 0.96. Conclusions: DECT and MRI provide high diagnostic confidence and image quality for assessing acute vertebral fractures. While DECT achieved high overall diagnostic accuracy in the analysis of BME presence and extent, MRI provided moderate sensitivity and lower confidence for evaluating fracture lines.
Objectives: To investigate the diagnostic accuracy of color-coded contrast-enhanced dual-energy CT virtual noncalcium (VNCa) reconstructions for the assessment of lumbar disk herniation compared to unenhanced VNCa imaging.
Methods: A total of 91 patients were retrospectively evaluated (65 years ± 16; 43 women) who had undergone third-generation dual-source dual-energy CT and 3.0-T MRI within an examination interval up to 3 weeks between November 2019 and December 2020. Eight weeks after assessing unenhanced color-coded VNCa reconstructions for the presence and degree of lumbar disk herniation, corresponding contrast-enhanced portal venous phase color-coded VNCa reconstructions were independently analyzed by the same five radiologists. MRI series were additionally analyzed by one highly experienced musculoskeletal radiologist and served as reference standard.
Results: MRI depicted 210 herniated lumbar disks in 91 patients. VNCa reconstructions derived from contrast-enhanced CT scans showed similar high overall sensitivity (93% vs 95%), specificity (94% vs 95%), and accuracy (94% vs 95%) for the assessment of lumbar disk herniation compared to unenhanced VNCa images (all p > .05). Interrater agreement in VNCa imaging was excellent for both, unenhanced and contrast-enhanced CT (κ = 0.84 vs κ = 0.86; p > .05). Moreover, ratings for diagnostic confidence, image quality, and noise differed not significantly between unenhanced and contrast-enhanced VNCa series (all p > .05).
Conclusions: Color-coded VNCa reconstructions derived from contrast-enhanced dual-energy CT yield similar diagnostic accuracy for the depiction of lumbar disk herniation compared to unenhanced VNCa imaging and therefore may improve opportunistic retrospective lumbar disk herniation assessment, particularly in case of staging CT examinations.
Key Points
• Color-coded dual-source dual-energy CT virtual noncalcium (VNCa) reconstructions derived from portal venous phase yield similar high diagnostic accuracy for the assessment of lumbar disk herniation compared to unenhanced VNCa CT series (94% vs 95%) with MRI serving as a standard of reference.
• Diagnostic confidence, image quality, and noise levels differ not significantly between unenhanced and contrast-enhanced portal venous phase VNCa dual-energy CT series.
• Dual-source dual-energy CT might have the potential to improve opportunistic retrospective lumbar disk herniation assessment in CT examinations performed for other indications through reconstruction of VNCa images.
Streams and rivers are characterised by the presence of various chemicals of emerging concern (CECs), including pesticides, pharmaceuticals, personal care products, and industrial chemicals. While these chemicals are found usually only in low (ng/L) concentrations, they might still harm aquatic life and disrupt the ecological balance of aquatic ecosystems due to their high ecotoxicological potency. Environmental risk assessments that account for the complexity of exposures are needed in order to evaluate the toxic pressure of these chemicals, which also provide suggestions for risk mitigation and management, if necessary. Currently, most studies on the co-occurrence and environmental impacts of CECs are conducted in countries of the Global North, leaving massive knowledge gaps in countries of the Global South.
In this study, we implement a multi-scenario risk assessment strategy to improve the assessment of both the exposure and hazard components in the chemical risk assessment process. Our strategy incorporates a systematic consideration and weighting of CECs that were not detected, as well as an evaluation of the uncertainties associated with Quantitative Structure-Activity Relationships (QSARs) predictions for chronic ecotoxicity. Furthermore, we present a novel approach to identifying mixture risk drivers. To expand our knowledge beyond well-studied aquatic ecosystems, we applied this multi-scenario strategy to the River Aconcagua basin of Central Chile. The analysis revealed that the concentrations of CECs exceeded acceptable risk thresholds for selected organism groups and the most vulnerable taxonomic groups. Streams flowing through agricultural areas and sites near the river mouth exhibited the highest risks. Notably, the eight risk drivers among the 153 co-occurring chemicals accounted for 66-92% of the observed risks in the river basin. Six of them are pesticides and pharmaceuticals, chemical classes known for their high biological activity in specific target organisms.
Despite recent advances in the treatment of metastatic prostate cancer (PCa), resistance development after taxane treatments is inevitable, necessitating effective options to combat drug resistance. Previous studies indicated antitumoral properties of the natural compound amygdalin. However, whether amygdalin acts on drug-resistant tumor cells remains questionable. An in vitro study was performed to investigate the influence of amygdalin (10 mg/mL) on the growth of a panel of therapy-naïve and docetaxel- or cabazitaxel-resistant PCa cell lines (PC3, DU145, and LNCaP cells). Tumor growth, proliferation, clonal growth, and cell cycle progression were investigated. The cell cycle regulating proteins (phospho)cdk1, (phospho)cdk2, cyclin A, cyclin B, p21, and p27 and the mammalian target of rapamycin (mTOR) pathway proteins (phospho)Akt, (phospho)Raptor, and (phospho)Rictor as well as integrin β1 and the cytoskeletal proteins vimentin, ezrin, talin, and cytokeratin 8/18 were assessed. Furthermore, chemotactic activity and adhesion to extracellular matrix components were analyzed. Amygdalin dose-dependently inhibited tumor growth and reduced tumor clones in all (parental and resistant) PCa cell lines, accompanied by a G0/G1 phase accumulation. Cell cycle regulating proteins were significantly altered by amygdalin. A moderate influence of amygdalin on tumor cell adhesion and chemotaxis was observed as well, paralleled by modifications of cytoskeletal proteins and the integrin β1 expression level. Amygdalin may, therefore, block tumor growth and disseminative characteristics of taxane-resistant PCa cells. Further studies are warranted to determine amygdalin’s value as an antitumor drug.
We study how species richness of arthropods relates to theories concerning net primary productivity, ambient energy, water-energy dynamics and spatial environmental heterogeneity. We use two datasets of arthropod richness with similar spatial extents (Scandinavia to Mediterranean), but contrasting spatial grain (local habitat and country). Samples of ground-dwelling spiders, beetles, bugs and ants were collected from 32 paired habitats at 16 locations across Europe. Species richness of these taxonomic groups was also determined for 25 European countries based on the Fauna Europaea database. We tested effects of net primary productivity (NPP), annual mean temperature (T), annual rainfall (R) and potential evapotranspiration of the coldest month (PETmin) on species richness and turnover. Spatial environmental heterogeneity within countries was considered by including the ranges of NPP, T, R and PETmin. At the local habitat grain, relationships between species richness and environmental variables differed strongly between taxa and trophic groups. However, species turnover across locations was strongly correlated with differences in T. At the country grain, species richness was significantly correlated with environmental variables from all four theories. In particular, species richness within countries increased strongly with spatial heterogeneity in T. The importance of spatial heterogeneity in T for both species turnover across locations and for species richness within countries suggests that the temperature niche is an important determinant of arthropod diversity. We suggest that, unless climatic heterogeneity is constant across sampling units, coarse-grained studies should always account for environmental heterogeneity as a predictor of arthropod species richness, just as studies with variable area of sampling units routinely consider area.
Hintergrund: Im Rahmen der Erforschung von Mechanismen der Presbyopie-Entstehung hat das Interesse an Methoden zur Linsendensitometrie wieder zugenommen. Für spezielle Fragestellungen sind flexible Untersuchungsmethoden notwendig.
Methoden: Basierend auf Aufnahmen mit der Scheimpflug-Kamera Pentacam HR (Oculus, Wetzlar) wurde ein MATLAB-Programm (V7.0, The MathWorks) erstellt, um größere Datenmengen automatisiert auszuwerten. Die Erkennung der Pupillenmitte als Referenzpunkt erfolgt mittels eines Randerkennungsalgorithmus. Als Kennzahlen dienen klassische Parameter der beschreibenden Statistik (Mittel, Minimum, Maximum, Standardabweichung und Variationskoeffizient) für einen definierten rechteckigen Bereich und für die zentrale vertikale Achse.
Ergebnisse: In einer Präliminarserie von 18 Augen war eine automatisierte Messung mit korrekter Pupillenerkennung in 80% der Fälle möglich. Verglichen mit der hersteller-eigenen Software (Pentacam 6.03r11) besitzt das eigene Programm eine erweiterte Spannweite der Messwerte. Die Messwerte können automatisch nach Excel (Microsoft) exportiert werden. Ein modularer Aufbau ermöglicht eine flexible Erweiterung für weitere Fragestellungen (z.B. Quantifizierung von Kern- und Rindentrübungen).
Schlussfolgerungen: Mittels eines selbst programmierten MATLAB-basierten Programmes kann eine automatisierte Messung und Analyse von linsndensitometrischen Parametern durchgeführt werden.