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The aim of this study was to integrate an antibacterial agent into implant materials to prevent infection and to investigate the aging behavior of the plastics in physiological solution as a function of filler type and proportion as well as of the process parameters. The active ingredient that is incorporated into the polymer during compounding should remain effective in the body over a long period of time. With varied melt processing conditions, composites made of a biodegradable polylactide (PLA) were mixed with tricalcium phosphate (TCP) and zinc oxide (ZnO) as an antibacterial agent. Hydroxyapatite (HAP) and zinc oxide were incorporated into a non‐degradable polyetheretherketone (PEEK). The material properties of the composites were characterised and investigated with regard to their in vitro behaviour. The investigations were carried out with gel permeation chromatography (GPC), differential scanning calorimetry (DSC), tensile tests, recording of the mass change during storage and colony forming units test (CFU). Over the investigated ageing period of 9 months in phosphate buffered saline (PBS) at 37 °C the composites showed antibacterial efficacy against Escherichia coli. [ABSTRACT FROM AUTHOR]

Scanning acoustic microscopy (SAM) was used to investigate disbonding, delamination and blister formation in polymer coatings for different layer structures and initial defect depths during exposure to a corrosive environment. The time evolution of disbonding and blister initiation and their growth was investigated by analysing the SAM images, taken after defined times of exposure to an electrolyte solution (Harrison solution).From investigations of a model system of coatings on steel substrates, it was possible to differentiate between water and/or ion transport (i) through the coating and (ii) along the coating–steel interface. For samples without clear coat randomly distributed blisters appeared at the coating–steel interface after exposure to the electrolyte solution, irrespective of the location of initial defects. The random distribution of growing blisters is related to diffusion of water and/or ions through the coating and ‘nucleation’ at weak points of the substrate or within the polymer. For samples with clear coat a propagating migration front along the coating–steel interface of 3–4 µm height—starting from initial defects—was detected. The linear propagation of this front cannot be explained by Fickian diffusion. Therefore, it is discussed in terms of an accelerated diffusion or crack growth kinetics. Since blistering starts only at sites, where the migration front has passed, the presence of a thin water layer at the coating–steel interface, the loss of adhesion and the following corrosive processes are prerequisites for the nucleation of blisters. The blister growth shows a square-root time dependence. [ABSTRACT FROM AUTHOR]

Ba andBa Fourier transform nuclear magnetic resonance and nuclear quadrupole resonance investigations are reported in liquids resp. solids. From these measurements ratios of g-factors, hyperfine structure anomalies, magnetic moments, atomic shielding constants and the ratio of the quadrupole moments are evaluated using also data from literature. [ABSTRACT FROM AUTHOR]

Cu andCu NMR studies are reported in liquid and solid copper (I) compounds. Ratios of g-factors, nuclear magnetic moments and nuclear magnetic shielding constants in the atomic reference scale are given forCu andCu in a solution of Cu(I)(CHCN)BF in CHCN, which is a reasonable reference sample due to the relatively narrow NMR line. [ABSTRACT FROM AUTHOR]

Neurological events (NE) during primary stay in heart transplant (HTx) recipients may be associated with reduced outcome and survival. We screened all patients undergoing HTx in our center between 09/2010 and 04/2022 (n=241), and included 237 patients with complete data on occurrence of NE during primary stay. NE were defined as ischemic stroke, hemorrhage, hypoxic ischemic injury or acute symptomatic neurological dysfunction without CNS injury. The cohort (table 1) was divided in recipients with (n=35) and without (n=202) NE after HTx. Using linear regression analysis, association of NE after HTx and survival, was assessed. Functional disability after strokes was classified by the modified Rankin Scale (mRS). Recipients with NE showed worse outcome (details in Table 1), including longer ICU stay, longer mechanical ventilation and more severe infections. Re-sternotomy and mechanical life support (ECLS) post HTx was also significantly higher. Covariable-adjusted regression revealed significant independent association of NE and reduced 30-day (adj. HR 3.8, 95% CI 1.4-10.1, p=.008) and 1-year (adj. HR 3.4, 95% CI 1.3-9.2, p=.013) survival after HTx, confirmed by Kaplan-Meier survival (p <.001, see figure 1A). Those surviving show high severity of functional disability (58% mRS 5). Only a minority recovers completely one year after the event, with 66% at least still mildly disabled (mRS ≥2; see figure 1B). Neurological events post HTx were strongly and independently associated with worse postoperative outcome and reduced survival up to 5 years after heart transplantation. [ABSTRACT FROM AUTHOR]

Background: Mesenteric ischemia is a life-threatening condition with a complex etiology and diagnostics., Objective: Etiology, incidence, symptoms, and diagnostics of acute and chronic mesenteric ischemia., Material and Methods: Literature search via PubMed with a focus on studies on the epidemiology and diagnostics of mesenteric ischemia and analysis of existing international guidelines., Results: The incidence of acute mesenteric ischemia is given as 0.63-12.9 per 100,000 people per year. There are no sufficiently reliable figures for chronic mesenteric ischemia, but an incidence of up to 3 per 100,000 inhabitants per year is generally assumed. The three-phase computed tomography has the highest diagnostic specificity and sensitivity., Conclusion: In the presence of risk factors acute and chronic mesenteric ischemia should be considered as differential diagnoses in the presence of abdominal pain using three-phase computed tomography., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Purpose: Surgery for recurrent glioma provides cytoreduction and tissue for molecularly informed treatment. With mostly heavily pretreated patients involved, it is unclear whether the benefits of repeat surgery outweigh its potential risks., Methods: Patients receiving surgery for recurrent glioma WHO grade 2-4 with the goal of tissue sampling for targeted therapies were analyzed retrospectively. Complication rates (surgical, neurological) were compared to our institutional glioma surgery cohort. Tissue molecular diagnostic yield, targeted therapies and post-surgical survival rates were analyzed., Results: Between 2017 and 2022, tumor board recommendation for targeted therapy through molecular diagnostics was made for 180 patients. Of these, 70 patients (38%) underwent repeat surgery. IDH-wildtype glioblastoma was diagnosed in 48 patients (69%), followed by IDH-mutant astrocytoma (n = 13; 19%) and oligodendroglioma (n = 9; 13%). Gross total resection (GTR) was achieved in 50 patients (71%). Tissue was processed for next-generation sequencing in 64 cases (91%), and for DNA methylation analysis in 58 cases (83%), while immunohistochemistry for mTOR phosphorylation was performed in 24 cases (34%). Targeted therapy was recommended in 35 (50%) and commenced in 21 (30%) cases. Postoperatively, 7 patients (11%) required revision surgery, compared to 7% (p = 0.519) and 6% (p = 0.359) of our reference cohorts of patients undergoing first and second craniotomy, respectively. Non-resolving neurological deterioration was documented in 6 cases (10% vs. 8%, p = 0.612, after first and 4%, p = 0.519, after second craniotomy). Median survival after repeat surgery was 399 days in all patients and 348 days in GBM patients after repeat GTR., Conclusion: Surgery for recurrent glioma provides relevant molecular diagnostic information with a direct consequence for targeted therapy under a reasonable risk of postoperative complications. With satisfactory postoperative survival it can therefore complement a multi-modal glioma therapy approach., (© 2024. The Author(s).)

Background Neurologic events during primary stay in heart transplant (HTx) recipients may be associated with reduced outcome and survival, which we aim to explore with the current study. Methods and Results We screened and included all patients undergoing HTx in our center between September 2010 and December 2022 (n=268) and checked for the occurrence of neurologic events within their index stay. Neurologic events were defined as ischemic stroke, hemorrhage, hypoxic ischemic injury, or acute symptomatic neurologic dysfunction without central nervous system injury. The cohort was then divided into recipients with (n=33) and without (n=235) neurologic events after HTx. Using a multivariable Cox regression model, the association of neurologic events after HTx and survival was assessed. Recipients with neurologic events displayed a longer intensive care unit stay (30 versus 16 days; P =0.009), longer mechanical ventilation (192 versus 48 hours; P <0.001), and higher need for blood transfusion, and need for hemodialysis after HTx was substantially higher (81% versus 55%; P =0.01). Resternotomy (36% versus 26%; P =0.05) and mechanical life support (extracorporeal life support) after HTx (46% versus 24%; P =0.02) were also significantly higher in patients with neurologic events. Covariable-adjusted multivariable Cox regression analysis revealed a significant independent association of neurologic events and increased 30-day (hazard ratio [HR], 2.5 [95% CI, 1.0-6.0]; P =0.049), 1-year (HR, 2.2 [95% CI, 1.1-4.3]; P =0.019), and overall (HR, 2.5 [95% CI, 1.5-4.2]; P <0.001) mortality after HTx and reduced Kaplan-Meier survival up to 5 years after HTx ( P <0.001). Conclusions Neurologic events after HTx were strongly and independently associated with worse postoperative outcome and reduced survival up to 5 years after HTx.

Background: In patients with neuroendocrine liver metastasis (NELM), liver transplantation (LT) is an alternative to liver resection (LR), although the choice of therapy remains controversial. In this multicenter study, we aim to provide novel insight in this dispute., Methods: Following a systematic literature search, 15 large international centers were contacted to provide comprehensive data on their patients after LR or LT for NELM. Survival analyses were performed with the Kaplan-Meier method, while multivariable Cox regression served to identify factors influencing survival after either transplantation or resection. Inverse probability weighting and propensity score matching was used for analyses with balanced and equalized baseline characteristics., Results: Overall, 455 patients were analyzed, including 230 after LR and 225 after LT, with a median follow-up of 97 months [95% confidence interval (CI): 85-110 months]. Multivariable analysis revealed G3 grading as a negative prognostic factor for LR [hazard ratio (HR)=2.22, 95% CI: 1.04-4.77, P =0.040], while G2 grading (HR=2.52, 95% CI: 1.15-5.52, P =0.021) and LT outside Milan criteria (HR=2.40, 95% CI: 1.16-4.92, P =0.018) were negative prognostic factors in transplanted patients. Inverse probability-weighted multivariate analyses revealed a distinct survival benefit after LT. Matched patients presented a median overall survival (OS) of 197 months (95% CI: 143-not reached) and a 73% 5-year OS after LT, and 119 months (95% CI: 74-133 months) and a 52.8% 5-year OS after LR (HR=0.59, 95% CI: 0.3-0.9, P =0.022). However, the survival benefit after LT was lost if patients were transplanted outside Milan criteria., Conclusions: This multicentric study in patients with NELM demonstrates a survival benefit of LT over LR. This benefit depends on adherence to selection criteria, in particular low-grade tumor biology and Milan criteria, and must be balanced against potential risks of LT., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)

The crack propagation rate of environmental stress cracking was studied on high-density polyethylene compact tension specimens under static loading. Selected environmental liquids are distilled water, 2 wt% aqueous Arkopal N100 solution, and two model liquid mixtures, one based on solvents and one on detergents, representing stress cracking test liquids for commercial crop protection products. The different surface tensions and solubilities, which affect the energetic facilitation of void nucleation and craze development, are studied. Crack growth in surface-active media is strongly accelerated as the solvents induce plasticization, followed by strong blunting significantly retarding both crack initiation and crack propagation. The crack propagation rate for static load as a function of the stress intensity factor within all environments is found to follow the Paris-Erdogan law. Scanning electron micrographs of the fracture surface highlight more pronounced structures with both extensive degrees of plasticization and reduced crack propagation rate, addressing the distinct creep behavior of fibrils. Additionally, the limitations of linear elastic fracture mechanisms for visco-elastic polymers exposed to environmental liquids are discussed.

The slowing down or stalling of replication forks is commonly known as replication stress and arises from multiple causes such as DNA lesions, nucleotide depletion, RNA-DNA hybrids, and oncogene activation. The ataxia telangiectasia and Rad3-related kinase (ATR) plays an essential role in the cellular response to replication stress and inhibition of ATR has emerged as therapeutic strategy for the treatment of cancers that exhibit high levels of replication stress. However, the cellular signaling induced by replication stress and the substrate spectrum of ATR has not been systematically investigated. In this study, we employed quantitative MS-based proteomics to define the cellular signaling after nucleotide depletion-induced replication stress and replication fork collapse following ATR inhibition. We demonstrate that replication stress results in increased phosphorylation of a subset of proteins, many of which are involved in RNA splicing and transcription and have previously not been associated with the cellular replication stress response. Furthermore, our data reveal the ATR-dependent phosphorylation following replication stress and discover novel putative ATR target sites on MCM6, TOPBP1, RAD51AP1, and PSMD4. We establish that ATR inhibition rewires cellular signaling networks induced by replication stress and leads to the activation of the ATM-driven double-strand break repair signaling., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In the last years, non-destructive ultrasonic testing methods are more and more frequently employed in order to investigate the drying and curing processes of different coatings. Among them an ultrasonic reflection method was developed allowing the simultaneous measurement with longitudinal and transversal waves. In order to generate the ultrasonic pulse, piezoelectric ceramics or oxides are usually used as transducer materials which are connected to a delay line. Here, we demonstrate a similar approach for the ultrasonic reflection method installing piezoelectric polymers as ultrasonic transducer materials. In detail, poly(vinylidene fluoride and trifluoroethylene) [P(VDF-TrFE)] copolymers were prepared as piezoelectric transducer layers directly onto the metallization of glass delay lines avoiding additional bonding processes. The film preparation was carried out by solvent casting the polymer onto an area with a diameter of 12 mm and is optimized so that relatively homogeneous polymer layers with thicknesses between 14 and 35 μm are adjusted by the deposited amount of the polymer. Electrical poling renders the polymer piezoelectric. The ultrasonic properties of the P(VDF-TrFE) transducer and their usability for the ultrasonic reflection method are described also in comparison to previous measurements using LiNbO(3) transducer.