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A new direction toward the future of orthopedic implants is to combine biodegradable Mg alloys with permanent Ti to produce selectively biodegradable hybrid joints for advanced tissue engineering. However, the strong galvanic corrosion between Mg and Ti is a major issue to be considered. This work aims to explore plasma electrolytic oxidation (PEO) as a single-step coating treatment to allow for an acceptable degradation behavior of MgTi hybrid systems. To this end, MgTi hybrid joints were produced through the heat treatment of Mg-0.6Ca and commercially pure Ti specimens at 640 °C for 8 h. A single-step PEO treatment was then employed to create a protective layer on the surface of hybrid couples. Even though the scanning electron microscopy (SEM) images showed only a porosity of 6% and 12% within the PEO layers on single Mg and MgTi couples, 3D investigation of the synchrotron-based microtomography data demonstrated a porosity of 18% and 30% with a considerable number of interconnected pores. According to the electrochemical impedance spectroscopy measurements, the impedance modulus at all frequencies on coated MgTi coupled specimens was lower than that on the coated single Mg-0.6Ca and pure Ti. However, the application of PEO treatment significantly decreased the strong galvanic degradation of Mg-0.6Ca in contact with Ti. The results of hydrogen evolution tests revealed that PEO-treated MgTi couples showed a similar degradation behavior as the single alloy during the first day of immersion.

The study is focussing towards Metal Injection Moulding (MIM) of Mg-alloys for biomedical implant applications. Especially the influence of the sintering processing necessary for the consolidation of the finished part is in focus of this study. In doing so, the chosen high strength EZK400 Mg-alloy powder material was sintered using different sintering support bottom plate materials to evaluate the possibility of iron impurity pick up during sintering. It can be shown that iron pick up took place from the steel bottom plate into the specimen. Despite the fact that a separating boron nitrite (BN) barrier layer was used and the Mg-Fe phase diagram is not predicting any significant solubility to each other. As a result of this study a new bottom plate material not harming the sintering and the biodegradation performance of the as sintered material, namely a carbon plate material, was found. Keywords: Magnesium, Mg alloy, Sintering, MIM, Powder metallurgy, Biodegradable implant, EZK400

Nonfullerene acceptors (NFAs) have dramatically improved the power conversion efficiency (PCE) of organic photovoltaics (OPV) in recent years; however, their device stability currently remains a bottleneck for further technological progress. Photocatalytic decomposition of nonfullerene acceptor molecules at metal oxide electron transport layer (ETL) interfaces has in several recent reports been demonstrated as one of the main degradation mechanisms for these high-performing OPV devices. While some routes for mitigating such degradation effects have been proposed, e.g., through a second layer integrated on the ETL surface, no clear strategy that complies with device scale-up and application requirements has been presented to date. In this work, it is demonstrated that the development of sputtered titanium oxide layers as ETLs in nonfullerene acceptor based OPV can lead to significantly enhanced device lifetimes. This is achieved by tuning the concentration of defect states at the oxide surface, via the reactive sputtering process, to mitigate the photocatalytic decomposition of NFA molecules at the metal oxide interlayers. Reduced defect state formation at the oxide surface is confirmed through X-ray photoelectron spectroscopy (XPS) studies, while the reduced photocatalytic decomposition of nonfullerene acceptor molecules is confirmed via optical spectroscopy investigations. The PBDB-T:ITIC organic solar cells show power conversion efficiencies of around 10% and significantly enhanced photostability. This is achieved through a reactive sputtering process that is fully scalable and industry compatible.

The mortality rate of newborns with severe congenital heart disease (CHD) has significantly decreased over the past few decades. However, many of these children experience neurological impairments, particularly following a hypoxic cardiac arrest. The use of extracorporeal membrane oxygenation (ECMO) has been considered an effective treatment for severe hypoxia in CHD cases. Various clinical studies have examined the use of ECMO for resuscitation after hypoxic cardiac arrest, but the results have been contradictory, showing a significant incidence of both mortality and morbidity in some studies while others report good outcome. In order to investigate the mechanisms behind brain injury associated with extracorporeal circulation, we have developed a neonatal porcine model of hypoxia-induced cardiac arrest followed by veno-arterial ECMO therapy., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Semisolid powder molding was used to prepare the medical Mg-6Zn alloy; in order to further improve its degradation adaptability, 0.5 and 1 wt % Mn were added. Then, the effect of the forming temperature (540, 560, 580, and 600 °C) on the in vitro degradation behavior of the prepared Mg-6Zn- x Mn ( x = 0.5, 1 wt %) was analyzed, and the optimized alloy was obtained. Finally, the biocompatibility and in vivo degradation performance of the optimized and Mn-free alloys were evaluated. Importantly, single-photon emission tomographic imaging (SPECT/CT) was first applied to monitor the in vivo degradation process. The results show that the corrosion mechanism of the Mn-free alloy is microgalvanic corrosion control with corrosive pitting. After adding Mn, the in vitro degradation rate decreases by half (0.17 ± 0.01 mm/year) as the forming temperature increases to 600 °C, and Mg-6Zn-1Mn prepared at 600 °C is the optimized alloy. Mn addition improves the corrosion product film protection and discontinuous secondary phases, and thus, the corrosion mechanism is changed to corrosive pitting control. Additionally, semisolid powder molding is an easy method to prepare alloys with low average pore interconnectivity (<10%), which is helpful for slowing down the degradation rate. The Mn-containing alloy has better biocompatibility, with a cytotoxicity of grade 0-1, due to its lower degradation rate. The in vivo corrosion rate of the Mn-free alloy is 0.19 mm/year after 28 days of implantation, which was precisely detected by SPECT/CT in real-time. The long-term in vivo degradation adaptability of Mn-free and Mn-containing alloys was not correctly presented, which may be due to the unreasonable bone defect model causing implant displacement. However, both of these alloys cause no obvious inflammation and show good healing. In summary, semisolid powder molding is a potentially promising technique to prepare medical Mg alloys, and nuclear imaging is an effective in vivo degradation evaluation method.

The diagnostic evaluation of homologous recombination deficiency (HRD) is central to define targeted therapy strategies for patients with ovarian carcinoma. We evaluated HRD in 514 ovarian carcinoma samples by next-generation sequencing of DNA libraries, including BRCA1/BRCA2 and 26,523 single-nucleotide polymorphisms using the standardized Myriad HRD assay, with the predefined cut point of ≥42 for a positive genomic instability score (GIS). All samples were measured in the central Myriad laboratory and in an academic molecular pathology laboratory. A positive GIS was detected in 196 (38.1%) of tumors, whereas 318 (61.9%) were GIS negative. Combining GIS and BRCA mutations, a total of 200 (38.9%) of the 514 tumors were HRD positive. A positive GIS was significantly associated with high-grade serous histology (P < 0.000001), grade 3 tumors (P = 0.001), and patient age <60 years (P = 0.0003). The concordance between both laboratories for the GIS status was 96.9% (P < 0.000001), with a sensitivity of 94.6% and a specificity of 98.4%. Concordance for HRD status was 97.1% (499 of 514 tumors). The percentage of HRD-positive tumors in our real-life cohort was similar to the proportion observed in the recently published PAOLA-1 trial, with high concordance between central and local laboratories. Our results support introduction of the standardized HRD assay in academic molecular pathology laboratories, thus broadening access to personalized oncology strategies for patients with ovarian cancer worldwide., (Copyright © 2022 Association for Molecular Pathology and American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Rodent models are commonly used in pre-clinical research of magnesium (Mg)-based and other types of biomaterials for fracture treatment. Most studies selected unstable fixation methods, and there is a lack of multimodal longitudinal in vivo monitoring of bone healing. The purpose of this study is to develop a rat femoral fracture model stabilized by external fixation with intra-medullary Mg implant, and to investigate the dynamic bone union process with several imaging techniques offering complementing insights into the process. Pure Mg pins were prepared, followed by an in vitro degradation test. Male Sprague-Dawley rats in the experimental group underwent femoral osteotomy stabilized by external fixators with intra-medullary implantation of Mg pins, and the control group underwent external fixation without intra-medullary implants. Post-operative radiograph, micro-CT and B-mode ultrasonography were acquired directly after surgery, and re-examined at week 4, 8 and 12. Bone tissue volume, in vivo implant degradation, histological staining and MRI images were analyzed using ex vivo samples. Both groups achieved fracture union at week 12, and the dynamic healing process was illustrated by in vivo radiograph, micro-CT and ultrasonography. Bilateral whole femur ex vivo analysis further demonstrated increased ratio of bone tissue volume in the surgical femur with Mg implants, and in vivo degradation of Mg pins was slower than in vitro results. Titanium screws rather than intra-medullary Mg pins were the source of artifact in MRI. This pilot study showed the rat fracture model with external fixation and intra-medullary Mg implantation to be an effective method for dynamic in vivo monitoring of the bone healing process. Future application of the animal model may facilitate pre-clinical translational research of biodegradable orthopaedic implant materials for fracture treatment.

Fused filament fabrication (FFF) is a new procedure for the production of plastic parts, particularly if the parts have a complex geometry and are only needed in a limited quantity, e.g., in specific medical applications. In addition to the production of parts which are purely composed of polymers, fused filament fabrication can be successfully applied for the preparation of green bodies for sintering of metallic implant materials in medical applications. In this case, highly filled polymer-metal feedstocks, which contain a variety of polymeric components, are used. In this study, we focus on various polymer-metal feedstocks, investigate the rheological properties of these materials, and relate them to our results of FFF experiments. Small amplitudes of shear oscillations reveal that the linear range of the polymer-metal feedstocks under investigation is very small, which is caused by elastic and viscous interactions between the metallic particles. These interactions strongly influence or even dominate the flow properties of the feedstock depending on the applied shear stress. The magnitude of the complex viscosity strongly increases with decreasing angular frequency, which indicates the existence of an apparent yield stress. The viscosity increase caused by the high powder loading needed for sintering limits the maximum printing velocity and the minimum layer height. The apparent yield stress hinders the formation of smooth surfaces in the FFF process and slows down the welding of deposited layers. The influence of composition on the processing parameters (suitable temperature range) and part properties (e.g., surface roughness) is discussed on the basis of rheological data.

Some β-Ti alloys, such as Ti-Nb-Ta-Zr (TNTZ) alloys, exhibit a low Young's modulus and excellent biocompatibility. These alloys are promising new generation biomedical implant materials. Selective laser melting (SLM) can further enable customer-specific manufacturing of β-Ti alloys to satisfy the ever-increasing need for enhanced biomedical products. In this study, we quantitatively determined the relationships between porosity, yield strength, and Young's modulus of SLM-prepared TNTZ lattices. The study constitutes a critical step toward understanding the behavior of the lattice and eventually enables tuning the Young's modulus to match that of human bones. Fatigue properties were also investigated on as-printed lattices in terms of the stress limit. The biocompatibility study included a routine evaluation of the relative cell growth rate and a proteomics analysis using a common mouse fibroblast cell line, L929. The results indicated that the as-printed TNTZ samples exhibited evidence of protein proliferation of the L929 cells, particularly P06733, and that those proteins are responsible for biological processes and molecular functions. They in turn may have promoted cell regeneration, cell motility, and protein binding, which at least partially explains the good biocompatibility of the as-printed TNTZ at the protein level. The study highlights the promising applications of additively manufactured TNTZ as a bone-replacing material from mechanical and biocompatibility perspectives., Competing Interests: Declaration of competing interest The authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (Copyright © 2020. Published by Elsevier B.V.)

Intravenous leiomyomatosis (IVLM) is an unusual neoplasm derived from uterine smooth muscle cells seen in patients with uterine leiomyomas. The typical histological features of IVLM consist of benign smooth muscle cells present within venous vascular spaces of the uterine wall. Increasing intravascular and intracardial spread of IVLM may lead to life-threatening clinical complications. Thorough pathological study of routine hysterectomy specimens may lead to the diagnosis of IVLM. Most affected patients will be cardiologically asymptomatic at the time of diagnosis. Herein, the relatively unknown clinical and morphological aspects of IVLM are presented and discussed.

This report reviews the effects of chemical, physical, and mechanical surface treatments on the degradation behavior of Mg alloys via their influence on the roughness and surface morphology. Many studies have been focused on technically-used AZ alloys and a few investigations regarding the surface treatment of biodegradable and Al-free Mg alloys, especially under physiological conditions. These treatments tailor the surface roughness, homogenize the morphology, and decrease the degradation rate of the alloys. Conversely, there have also been reports which showed that rough surfaces lead to less pitting and good cell adherence. Besides roughness, there are many other parameters which are much more important than roughness when regarding the degradation behavior of an alloy. These studies, which indicate the relationship between surface treatments, roughness and degradation, require further elaboration, particularly for biomedical Mg alloy applications.