Comparison of Data-Dependent Acquisition, Data-Independent Acquisition, and Parallel Reaction Monitoring in Trapped Ion Mobility Spectrometry-Time-of-Flight Tandem Mass Spectrometry-Based Lipidomics.

The parallel accumulation-serial fragmentation (PASEF) approach based on trapped ion mobility spectrometry (TIMS) enables mobility-resolved fragmentation and a higher number of fragments in the same time period compared to conventional MS/MS experiments. Furthermore, the ion mobility dimension offers novel approaches for fragmentation. Using parallel reaction monitoring (prm), the ion mobility dimension allows a more accurate selection of precursor windows, while using data-independent aquisition (dia) spectral quality is improved through ion-mobility filtering. Owing to favorable implementation in proteomics, the transferability of these PASEF modes to lipidomics is of great interest, especially as a result of the high complexity of analytes with similar fragments. However, these novel PASEF modes have not yet been thoroughly evaluated for lipidomics applications. Therefore, data-dependent acquisition (dda)-, dia-, and prm-PASEF were compared using hydrophilic interaction liquid chromatography (HILIC) for phospholipid class separation in human plasma samples. Results show that all three PASEF modes are generally suitable for usage in lipidomics. Although dia-PASEF achieves a high sensitivity in generating MS/MS spectra, the fragment-to-precursor assignment for lipids with both, similar retention time as well as ion mobility, was difficult in HILIC-MS/MS. Therefore, dda-PASEF is the method of choice to investigate unknown samples. However, the best data quality was achieved by prm-PASEF, owing to the focus on fragmentation of specified targets. The high selectivity and sensitivity in generating MS/MS spectra of prm-PASEF could be a potential alternative for targeted lipidomics, e.g., in clinical applications.

Interstitial lung disease in patients with anti-neutrophil cytoplasm antibody-associated vasculitis: an update on pathogenesis and treatment.

PURPOSE OF REVIEW: Interstitial lung disease (ILD) is now recognized as a common complication of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV), especially myeloperoxidase (MPO)-ANCA-positive AAV and microscopic polyangiitis (MPA). This review focuses on current concepts pertaining to the pathogenesis, clinical assessment, and management of AAV-ILD. RECENT FINDINGS: ILD is typically identified before or at the onset of systemic AAV, and usual interstitial pneumonia (UIP) is the most common CT pattern. MPO-ANCA production, neutrophil extracellular traps formation, reactive oxidative species production, complement activation, environmental exposures, and genetic background might play a role in the pathogenesis of AAV-ILD. Recent research has identified promising biomarkers as potential diagnostic and prognostic tools in AAV-ILD. The optimal treatment for AAV-ILD is not well defined but might rely on a combination of immunosuppression and antifibrotics, especially in patients with progressive lung fibrosis. Despite the effectiveness of current therapies for AAV, the outcome of patients with AAV-ILD remains poor. SUMMARY: ANCA screening should be considered in patients with newly diagnosed ILD. Management of AAV-ILD should be overviewed by a collaborative team comprising vasculitis experts and respirologists. VIDEO ABSTRACT: http://links.lww.com/COPM/A33.

Restrictive versus high-dose oxygenation strategy in post-arrest management following adult non-traumatic cardiac arrest: a meta-analysis.

PURPOSE: Neurological damage is the main cause of death or withdrawal of care in comatose survivors of cardiac arrest (CA). Hypoxemia and hyperoxemia following CA were described as potentially harmful, but reports were inconsistent. Current guidelines lack specific oxygen targets after return of spontaneous circulation (ROSC). OBJECTIVES: The current meta-analysis assessed the effects of restrictive compared to high-dose oxygenation strategy in survivors of CA. METHODS: A structured literature search was performed. Randomized controlled trials (RCTs) comparing two competing oxygenation strategies in post-ROSC management after CA were eligible. The primary end point was short-term survival (≤ 90 days). The meta-analysis was prospectively registered in PROSPERO database (CRD42023444513). RESULTS: Eight RCTs enrolling 1941 patients were eligible. Restrictive oxygenation was applied to 964 patients, high-dose regimens were used in 977 participants. Short-term survival rate was 55.7% in restrictive and 56% in high-dose oxygenation group (8 trials, RR 0.99, 95% CI 0.90 to 1.10, P = 0.90, I2 = 18%, no difference). No evidence for a difference was detected in survival to hospital discharge (5 trials, RR 0.98, 95% CI 0.79 to 1.21, P = 0.84, I2 = 32%). Episodes of hypoxemia more frequently occurred in restrictive oxygenation group (4 trials, RR 2.06, 95% CI 1.47 to 2.89, P = 0.004, I2 = 13%). CONCLUSION: Restrictive and high-dose oxygenation strategy following CA did not result in differences in short-term or in-hospital survival. Restrictive oxygenation strategy may increase episodes of hypoxemia, even with restrictive oxygenation targets exceeding intended saturation levels, but the clinical relevance is unknown. There is still a wide gap in the evidence of optimized oxygenation in post-ROSC management and specific targets cannot be concluded from the current evidence.

Effects of plant diversity on species-specific herbivory: patterns and mechanisms.

Invertebrate herbivory can shape plant communities when impacting growth and fitness of some plant species more than other species. Previous studies showed that herbivory varies among plant species and that species-specific herbivory is affected by the diversity of the surrounding plant community. However, mechanisms underlying this variation are still poorly understood. In this study, we investigate how plant traits and plant apparency explain differences in herbivory among plant species and we explore the effect of plant community diversity on these species-specific relationships. We found that species differed in the herbivory they experienced. Forbs were three times more damaged by herbivores than grasses. Variability within grasses was caused by differences in leaf dry matter content (LDMC). Furthermore, higher plant diversity increased herbivory on 15 plant species and decreased herbivory on nine species. Variation within forb and grass species in their response to changing plant diversity was best explained by species' physical resistance (LDMC, forbs) and biomass (grasses). Overall, our results show that herbivory and diversity effects on herbivory differ among species, and that, depending on the plant functional group, either species-specific traits or apparency are driving those differences. Thus, herbivores might selectively consume palatable forbs or abundant grasses with contrasting consequences for plant community composition in grasslands dominated by either forbs or grasses.

Dusty starburst galaxies in the early Universe as revealed by gravitational lensing.

In the past decade, our understanding of galaxy evolution has been revolutionized by the discovery that luminous, dusty starburst galaxies were 1,000 times more abundant in the early Universe than at present. It has, however, been difficult to measure the complete redshift distribution of these objects, especially at the highest redshifts (z > 4). Here we report a redshift survey at a wavelength of three millimetres, targeting carbon monoxide line emission from the star-forming molecular gas in the direction of extraordinarily bright millimetre-wave-selected sources. High-resolution imaging demonstrates that these sources are strongly gravitationally lensed by foreground galaxies. We detect spectral lines in 23 out of 26 sources and multiple lines in 12 of those 23 sources, from which we obtain robust, unambiguous redshifts. At least 10 of the sources are found to lie at z > 4, indicating that the fraction of dusty starburst galaxies at high redshifts is greater than previously thought. Models of lens geometries in the sample indicate that the background objects are ultra-luminous infrared galaxies, powered by extreme bursts of star formation.

Observation of the spin Nernst effect.

The observation of the spin Hall effect triggered intense research on pure spin current transport. With the spin Hall effect, the spin Seebeck effect and the spin Peltier effect already observed, our picture of pure spin current transport is almost complete. The only missing piece is the spin Nernst (-Ettingshausen) effect, which so far has been discussed only on theoretical grounds. Here, we report the observation of the spin Nernst effect. By applying a longitudinal temperature gradient, we generate a pure transverse spin current in a Pt thin film. For readout, we exploit the magnetization-orientation-dependent spin transfer to an adjacent yttrium iron garnet layer, converting the spin Nernst current in Pt into a controlled change of the longitudinal and transverse thermopower voltage. Our experiments show that the spin Nernst and the spin Hall effect in Pt are of comparable magnitude, but differ in sign, as corroborated by first-principles calculations.

Deletion of GARP on mouse regulatory T cells is not sufficient to inhibit the growth of transplanted tumors.

GARP is a transmembrane protein that presents latent TGF-ß1 on the surface of regulatory T cells (Tregs). Neutralizing anti-GARP monoclonal antibodies that prevent the release of active TGF-ß1, inhibit the immunosuppressive activity of human Tregs in vivo. In this study, we investigated the contribution of GARP on mouse Tregs to immunosuppression in experimental tumors. Unexpectedly, Foxp3 conditional garp knockout (KO) mice challenged orthotopically with GL261 tumor cells or subcutaneously with MC38 colon carcinoma cells did not show prolonged survival or delayed tumor growth. Also, the suppressive function of KO Tregs was similar to that of wild type Tregs in the T cell transfer model in allogeneic, immunodeficient mice. In conclusion, garp deletion in mouse Tregs is not sufficient to impair their immunosuppressive activity in vivo.

Direct Frequency-Comb-Driven Raman Transitions in the Terahertz Range.

We demonstrate the use of a femtosecond frequency comb to coherently drive stimulated Raman transitions between terahertz-spaced atomic energy levels. More specifically, we address the 3d ^{2}D_{3/2} and 3d ^{2}D_{5/2} fine structure levels of a single trapped ^{40}Ca^{+} ion and spectroscopically resolve the transition frequency to be ν_{D}=1,819,599,021,534±8 Hz. The achieved accuracy is nearly a factor of five better than the previous best Raman spectroscopy, and is currently limited by the stability of our atomic clock reference. Furthermore, the population dynamics of frequency-comb-driven Raman transitions can be fully predicted from the spectral properties of the frequency comb, and Rabi oscillations with a contrast of 99.3(6)% and millisecond coherence time have been achieved. Importantly, the technique can be easily generalized to transitions in the sub-kHz to tens of THz range and should be applicable for driving, e.g., spin-resolved rovibrational transitions in molecules and hyperfine transitions in highly charged ions.

Controlling the Local Electronic Properties of Si(553)-Au through Hydrogen Doping.

We propose a quantitative and reversible method for tuning the charge localization of Au-stabilized stepped Si surfaces by site-specific hydrogenation. This is demonstrated for Si(553)-Au as a model system by combining density functional theory simulations and reflectance anisotropy spectroscopy experiments. We find that controlled H passivation is a two-step process: step-edge adsorption drives excess charge into the conducting metal chain "reservoir" and renders it insulating, while surplus H recovers metallic behavior. Our approach illustrates a route towards microscopic manipulation of the local surface charge distribution and establishes a reversible switch of site-specific chemical reactivity and magnetic properties on vicinal surfaces.

A uniform method for the simultaneous blood group phenotyping of Fya , Fyb , Jka , Jkb , S, sÌ , P1, k applying lateral-flow technique.

BACKGROUND AND OBJECTIVES: A lateral flow assay for simultaneous blood group typing of ABO, RhD, C, E, c, e, Cw and K with stable end-point and without centrifugation is in routine use since several years (MDmulticard® ). The typing of extended phenotype parameters belonging to the Duffy, Kidd, MNSs blood group systems and others, however, has not yet been demonstrated for this technique. Reliable detection of Fyx , a weak Fyb phenotype with a pronounced quantitative reduction of the number of Fyb antigens on the erythrocyte surface, remains a weakness of current serological blood grouping techniques. MATERIAL AND METHODS: The performance characteristics of the following reagents were evaluated in donor and patient samples in lateral flow technology (MDmulticard® ): Anti-Fya , -Fyb , -Jka , -Jkb , -S, -s̅, -P1 and -k. The sensitivity to detect Fyx was in addition evaluated with Fyx positive samples, which had been preselected by MALDI-TOF MS-based genotyping. RESULTS: All results obtained with the MDmulticard® were in full accordance with those of the CE-certified reference products for all the eight reagent formulations used: Anti-Fya , -Fyb , -Jka , -Jkb , -S, -s̅, -P1 and -k. Also, all Fyx phenotypes of the selected population of 93 positive samples, originally identified by MALDI-TOF MS-based genotyping, were reliably detected by the lateral flow assay. CONCLUSION: Extended phenotype blood group parameters, including the serologically challenging Fyx phenotype, can be determined simultaneously, rapidly and accurately using the lateral flow (MDmulticard® ) technology, even in cases when IgG class antibodies are the only source of diagnostic antibodies.

A massive, cooling-flow-induced starburst in the core of a luminous cluster of galaxies.

In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2 × 10(45) erg s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.

Effects of arsenolipids on in vitro blood-brain barrier model.

Arsenic-containing hydrocarbons (AsHCs), a subgroup of arsenolipids (AsLs) occurring in fish and edible algae, possess a substantial neurotoxic potential in fully differentiated human brain cells. Previous in vivo studies indicating that AsHCs cross the blood-brain barrier of the fruit fly Drosophila melanogaster raised the question whether AsLs could also cross the vertebrate blood-brain barrier (BBB). In the present study, we investigated the impact of several representatives of AsLs (AsHC 332, AsHC 360, AsHC 444, and two arsenic-containing fatty acids, AsFA 362 and AsFA 388) as well as of their metabolites (thio/oxo-dimethylpropionic acid, dimethylarsinic acid) on porcine brain capillary endothelial cells (PBCECs, in vitro model for the blood-brain barrier). AsHCs exerted the strongest cytotoxic effects of all investigated arsenicals as they were up to fivefold more potent than the toxic reference species arsenite (iAsIII). In our in vitro BBB-model, we observed a slight transfer of AsHC 332 across the BBB after 6 h at concentrations that do not affect the barrier integrity. Furthermore, incubation with AsHCs for 72 h led to a disruption of the barrier at sub-cytotoxic concentrations. The subsequent immunocytochemical staining of three tight junction proteins revealed a significant impact on the cell membrane. Because AsHCs enhance the permeability of the in vitro blood-brain barrier, a similar behavior in an in vivo system cannot be excluded. Consequently, AsHCs might facilitate the transfer of accompanying foodborne toxicants into the brain.

Virology analyses of HCV genotype 4 isolates from patients treated with simeprevir and peginterferon/ribavirin in the Phase III RESTORE study.

Simeprevir is a hepatitis C virus NS3/4A protease inhibitor. Hepatitis C virus baseline NS3/4A polymorphisms and emerging mutations were characterized in treatment-naїve and treatment-experienced genotype 4-infected patients treated with simeprevir+peginterferon/ribavirin in the RESTORE study. Population sequencing of the NS3/4A region was performed and in vitro simeprevir activity against site-directed mutants or chimeric replicons with patient-derived NS3 protease sequences was assessed in a transient replicon assay. Simeprevir remained active against most (83/91 [91%]) baseline isolates tested in the chimeric replicon assay. Eight baseline isolates reduced simeprevir activity; these carried I132L or D168E substitutions reducing simeprevir median activity by 4.6- and 39-fold, respectively. Six of these eight isolates were from patients achieving sustained virologic response. Baseline NS3 Q80K polymorphism was not observed in the genotype 4-infected patients. Of the 107 simeprevir-treated patients, 37 did not achieve sustained virologic response for any reason. Of the 32 patients who failed treatment and had sequencing information, 28 (88%) had emerging mutations at NS3 positions 80, 122, 155, 156 and/or 168 at time of failure, similar to those in genotype 1. Emerging mutations were mainly D168V and D168E alone or combined with mutations at position 80. In general, isolates obtained at time of failure displayed high-level in vitro resistance to simeprevir (fold change ≥50) in a chimeric replicon assay with a median simeprevir fold change value of 440, consistent with observed mutations. In conclusion, emerging mutations in genotype 4 patients failing simeprevir+peginterferon/ribavirin treatment were similar to those in genotype 1 and conferred high-level resistance to simeprevir.

Intracoronary pressure measurement differences between anterior and posterior coronary territories.

INTRODUCTION: Intracoronary pressure measurements have improved assessment of angiographic intermediate coronary stenoses. Methodically, pressure equalization and actual measurements are frequently performed at different height levels, depending on the particular coronary territory analyzed. Considering a hypothetical influence of hydrostatic pressure and the supine position of the patient, differences in the results of intracoronary measurements between anterior and posterior vessels seem likely. The purpose of this study was to compare the results of intracoronary pressure measurements between anterior and posterior coronary territories. METHODS: Intracoronary pressure measurements of 214 coronary stenoses in 158 patients were analyzed. Fractional flow reserve (FFR) was measured in all stenosis and instantaneous wave-free ratio (iFR) in 197 stenoses in 144 patients. RESULTS: Both FFR (0.79 vs. 0.87, p < 0.001) and iFR values (0.86 vs. 0.94, p < 0.001) were significantly higher in posterior compared to anterior coronary vessels. Patients with only anterior or posterior lesions did not differ regarding clinical or lesion characteristics, in particular coronary stenosis severity (62.5 vs. 61.6 %, p = 0.27). CONCLUSIONS: Results of intracoronary measurements were systematically higher in the posterior coronary vessels when compared with anterior vessels. This phenomenon was independent of coronary stenosis severity or any clinical characteristics in our study population.

Effect of laser-activated irrigation on biofilms in artificial root canals.

AIM: To evaluate the antimicrobial effect of laser-activated irrigation (LAI) on biofilms formed in simulated root canals. METHODOLOGY: A dual-species biofilm of Enterococcus faecalis and Streptococcus mutans was grown in a resin root canal model. Biofilms were formed over 48 h and subsequently subjected to the following treatments, all executed for 20 s: syringe irrigation (SI) with a 27G needle, ultrasonically activated irrigation (UAI) with a size 20 Irrisafe file, and LAI with a 2940 nm Er:YAG laser (20 Hz, 50 µs, 20 or 40 mJ, conical fibre tip at two positions). Tests were performed with both sterile saline as well as NaOCl (2.5%) as the irrigant. Surviving bacteria were harvested and the number of CFU was determined by plate counting and compared across groups (anova, P ≤ 0.05). RESULTS: Using saline as the irrigant, significant reductions in viable counts compared to untreated controls were observed for ultrasonically activated irrigation (0.52 log10 reduction) and for all laser-activated irrigation groups (>1 log10 reduction), but not for syringe irrigation (<0.25 log10 reduction). The reductions in the laser-activated irrigation groups were significantly greater than those of ultrasonically activated irrigation. With NaOCl as the irrigant, significant reductions (>2.2 log10 units) in the number of attached bacteria were observed for all treatment groups with no significant differences between laser-activated and ultrasonically activated irrigation. CONCLUSIONS: Within the limitations of this in vitro set-up, laser-activated irrigation removed more biofilm than ultrasonically activated irrigation when using saline as the irrigant, indicating greater physical biofilm removal. The use of NaOCl resulted in greater biofilm reduction with no significant differences between treatment groups.

[Stroke in children and adolescents]. / Schlaganfall bei Kindern und Jugendlichen.

The occurrence of a stroke in children and adolescents constitutes a rare, critical event that is associated with substantial morbidity and mortality. In addition to the individual suffering for the young patient and the medical burden for the affected family, a stroke is also associated with high follow-up costs for the health system because of the necessary long-term rehabilitative treatment. Establishing an early and prompt diagnosis is of great therapeutic importance. Because of the rarity of the illness and the plethora of clinical manifestations, diagnosis is often delayed. The most frequent clinical presentation is an acute focal-neurological deficit, usually in the form of hemiparesis, but headache, seizures or alteration of consciousness may also be seen. Nowadays, the prompt performance of diffusion-weighted, blood-sensitive magnetic resonance imaging (MRI) constitutes the gold standard. The most relevant risk factors for the occurrence of a stroke in this age cohort are vasculopathies, infections, pathological cardiac conditions or coagulopathies. Recurrence of stroke is dependent on the underlying risk factors. In a substantial percentage of patients, residual neurological deficits are seen.Owing to a lack of randomized controlled trials in children and adolescents with stroke, the optimal treatment approach is still under debate. In addition to anti-platelet medication and heparinization, systematic intravenous thrombolysis and endovascular thrombectomy are other potentially effective treatment options. The long-term prognosis in children is dependent on establishing a correct, early diagnosis.

Platelet sequestration and activation during GalTKO.hCD46 pig lung perfusion by human blood is primarily mediated by GPIb, GPIIb/IIIa, and von Willebrand Factor.

BACKGROUND: Here, we ask whether platelet GPIb and GPIIb/IIIa receptors modulate platelet sequestration and activation during GalTKO.hCD46 pig lung xenograft perfusion. METHODS: GalTKO.hCD46 transgenic pig lungs were perfused with heparinized fresh human blood. Results from perfusions in which αGPIb Fab (6B4, 10 mg/l blood, n = 6), αGPIIb/IIIa Fab (ReoPro, 3.5 mg/l blood, n = 6), or both drugs (n = 4) were administered to the perfusate were compared to two additional groups in which the donor pig received 1-desamino-8-d-arginine vasopressin (DDAVP), 3 µg/kg (to pre-deplete von Willebrand Factor (pVWF), the main GPIb ligand), with or without αGPIb (n = 6 each). RESULTS: Platelet sequestration was significantly delayed in αGPIb, αGPIb+DDAVP, and αGPIb+αGPIIb/IIIa groups. Median lung "survival" was significantly longer (>240 vs. 162 min reference, p = 0.016), and platelet activation (as CD62P and ßTG) were significantly inhibited, when pigs were pre-treated with DDAVP, with or without αGPIb Fab treatment. Pulmonary vascular resistance rise was not significantly attenuated in any group, and was associated with residual thromboxane and histamine elaboration. CONCLUSIONS: The GPIb-VWF and GPIIb/IIIa axes play important roles in platelet sequestration and coagulation cascade activation during GalTKO.hCD46 lung xenograft injury. GPIb blockade significantly reduces platelet activation and delays platelet sequestration in this xenolung rejection model, an effect amplified by adding αGPIIb/IIIa blockade or depletion of VWF from pig lung.

Mechanistic insights into lithium ion battery electrolyte degradation - a quantitative NMR study.

The changes in electrolyte composition on the molecular level and the reaction mechanisms of electrolyte degradation upon thermal aging are monitored by quantitative NMR spectroscopy, revealing similar rates of degradation for pristine and already aged electrolytes. The data analysis is not in favor of an autocatalytic reaction mechanism based on OPF3 but rather indicates that the degradation of LiPF6 in carbonate based solvents proceeds via a complex sequence of "linear" reactions rather than a cyclic reaction pattern which is determined by the amount of water present in the samples. All investigated electrolytes are reasonably stable at temperatures of up to 60 °C in the presence of minor amounts or absence of water hence indicating that chemical instability of electrolyte components against water is decisive for degradation and an increase in temperature ("thermal aging") just accelerates the degradation impact of water.