Rapid separation of the major phospholipid classes on a single aminopropyl cartridge

A rapid method for the separation of the individual phospholipid classes phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS) and phosphatidylinositol (PI) by a single solid-phase extraction was developed. PC, PE, PS and PI were sequentially eluted from aminopropyl bonded silica with acetonitrile/n-propanol (2∶1, vol/vol), methanol, isopropanol/methanolic HCl (4∶1, vol/vol) and methanol/methanolic HCl (9∶1, vol/vol). Standard recoveries were over 95% for PC and PE and over 85% for PS and PI with undistorted fatty acid composition. The separation of complex lipid mixtures on aminopropyl minicolumns can be refined to the level of individual phospholipid classes.     

Tough reinforced open porous polymer foams via concentrated emulsion templating

Low-density but very resilient and robust polymer foams possessing an interconnected open porous network have been synthesised by the polymerisation of the continuous phase of concentrated or high internal phase emulsions containing polyethylene glycol dimethacrylate (PEGDMA) as main crosslinker. The synthesised polymer foams did not display the undesirable properties, such as brittleness and chalkiness, which are commonly observed for highly crosslinked porous polymer monoliths synthesised by the polymerisation of high internal phase emulsions. An effective way to improve the mechanical performance of open porous polymer foams is to raise the apparent foam density. Therefore, the continuous phase of the emulsions was increased up to 40 vol.%. The mechanical properties can be further increased by the incorporation of silica particles into the polymer. Methacryloxypropyltrimethoxysilane was added to the continuous phase to ensure that the silica particles were covalently bonded into the inorganic polymer network formed by the hydrolytic condensation of the silane groups. The addition of reinforcement increased the mechanical properties. The Young's modulus and the crush strength of the polymer foams increased by up to 360% and by up to 300%, respectively, in comparison to non-reinforced samples.     

Assessment of tailor-made HPMC-based matrix minitablets comprising a weakly basic drug compound

Tailor-made, pH-controlled matrix minitablets based on different HPMC types were developed comprising the weakly basic drug dipyridamole. The incorporation of pH modifiers, i.e., fumaric and succinic acid, enhanced the drug release at pH 6.8. Assessing the drug release, acid release, and the microenvironmental pH (pH_M) provided detailed understanding of pH-controlled mini-matrices.

The extent and duration of pH_M alteration was more pronounced in presence of fumaric acid. Minitablets based on the fast dissolving Methocel K100LV (≤ 100 cps) showed simultaneous release rates of dipyridamole and fumaric acid with a constant low average pH_M.     

Schäden an Parkdecks mit unzureichender rißbreitenbeschränkender Bewehrung

Damages to Parking Decks with insufficient reinforcement unable to limit crack width During construction of parking decks the reinforcement to limit crack widths is often measured and placed insufficiently. This lack of construction normally leads to uncontrollable crack formation. In order to guarantee the durability of the building during its service life precaution and restoration is necessary, i. e. the coating of the parking surface with crack bridging systems, possibly in combination with preceding filling actions of the cracks. With it the efficiency of the actions has to be aligned to the expected width of the cracks. In order to capture the change of crack width caused by weather in a realistic way, the changes should be measured under load and during changing temperatures. Relying on this research data, a realistic estimation of the expected crack width can be done.     

A Combined Experimental and Theoretical Study of HMX (Octogen,Octahydro‐1,3,5,7‐Tetranitro‐1,3,5,7‐Tetrazocine) in the Gas Phase

The structures of α‐ and β‐HMX were fully optimized and the vibrational frequencies computed at the hybrid DFT B3LYP/6‐31G(d, p) level of theory. The DCI+mass spectrum of HMX using ammonia (NH₃) as a “soft” ionising gas is reported. Field desorption mass spectrometry (FD) was used because of the high molecular intensities and low fragmentation. The FD spectrum shows only one significant peak at m/e 297 due to the protonated molecular ion [M+H]⁺. These observations clearly establish that under the conditions of CI and FD mass spectrometry experiments HMX is present in the gas phase (without decomposition) prior to the chemical ionisation.     

Kinetic Study on the Reactivity of Azanone (HNO) toward Cyclic C-Nucleophiles

Azanone (HNO) is an elusive electrophilic reactive nitrogen species of growing pharmacological and biological significance. Here, we present a comparative kinetic study of HNO reactivity toward selected cyclic C-nucleophiles under aqueous conditions at pH 7.4. We applied the competition kinetics method, which is based on the use of a fluorescein-derived boronate probe FlBA and two parallel HNO reactions: with the studied scavenger or with O₂ (k = 1.8 × 10⁴ M⁻¹s⁻¹). We determined the second-order rate constants of HNO reactions with 13 structurally diverse C-nucleophiles (k = 33–20,000 M⁻¹s⁻¹). The results show that the reactivity of HNO toward C-nucleophiles depends strongly on the structure of the scavenger. The data are supported with quantum mechanical calculations. A comprehensive discussion of the HNO reaction with C-nucleophiles is provided.     

Screening of Self-Assembling of Collagen IV Fragments into Stable Structures Potentially Useful in Regenerative Medicine

The aim of the research was to check whether it is possible to use fragments of type IV collagen to obtain, as a result of self-assembling, stable spatial structures that could be used to prepare new materials useful in regenerative medicine. Collagen IV fragments were obtained by using DMT/NMM/TosO⁻ as a coupling reagent. The ability to self-organize and form stable spatial structures was tested by the CD method and microscopic techniques. Biological studies covered: resazurin assay (cytotoxicity assessment) on BJ, BJ-5TA and C2C12 cell lines; an alkaline version of the comet assay (genotoxicity), Biolegend Legendplex human inflammation panel 1 assay (SC cell lines, assessment of the inflammation activity) and MTT test to determine the cytotoxicity of the porous materials based on collagen IV fragments. It was found that out of the pool of 37 fragments (peptides 1–33 and 2.1–2.4) reconstructing the outer sphere of collagen IV, nine fragments (peptides: 2, 4, 5, 6, 14, 15, 25, 26 and 30), as a result of self-assembling, form structures mimicking the structure of the triple helix of native collagens. The stability of spatial structures formed as a result of self-organization at temperatures of 4 °C, 20 °C, and 40 °C was found. The application of the MST method allowed us to determine the K_d of binding of selected fragments of collagen IV to ITGα1β1. The stability of the spatial structures of selected peptides made it possible to obtain porous materials based on their equimolar mixture. The formation of the porous materials was found for cross-linked structures and the material stabilized only by weak interactions. All tested peptides are non-cytotoxic against all tested cell lines. Selected peptides also showed no genotoxicity and no induction of immune system responses. Research on the use of porous materials based on fragments of type IV collagen, able to form stable spatial structures as scaffolds useful in regenerative medicine, will be continued.     

Analysis of Multiple Drug Resistance Mechanism in Different Types of Soft Tissue Sarcomas: Assessment of the Expression of ABC-Transporters,MVP, YB-1, and Analysis of Their Correlation with Chemosensitivity of Cancer Cells

Chemotherapy of soft tissue sarcomas (STS) is restricted by low chemosensitivity and multiple drug resistance (MDR). The purpose of our study was the analysis of MDR mechanism in different types of STS. We assessed the expression of ABC-transporters, MVP, YB-1, and analyzed their correlation with chemosensitivity of cancer cells. STS specimens were obtained from 70 patients without metastatic disease (2018–2020). Expression level of MDR-associated genes was estimated by qRT-PCR and cytofluorimetry. Mutations in ABC-transporter genes were captured by exome sequencing. Chemosensitivity (SI) of STS to doxorubicin (Dox), ifosfamide (Ifo), gemcitabine (Gem), and docetaxel (Doc) was analyzed in vitro. We found strong correlation in ABCB1, ABCC1, and ABCG2 expression. We demonstrated strong negative correlations in ABCB1 and ABCG2 expression with SI (Doc) and SI (Doc + Gem), and positive correlation of MVP expression with SI (Doc) and SI (Doc + Gem) in undifferentiated pleomorphic sarcoma. Pgp expression was shown in 5 out of 44 STS samples with prevalence of synovial sarcoma relapses and it is strongly correlated with SI (Gem). Mutations in MDR-associated genes were rarely found. Overall, STS demonstrated high heterogeneity in chemosensitivity that makes reasonable in vitro chemosensitivity testing to improve personalized STS therapy, and classic ABC-transporters are not obviously involved in MDR appearance.     

Biodegradable Fluorescent Nanoparticles for Endoscopic Detection of Colorectal Carcinogenesis

Early and comprehensive endoscopic detection of colonic dysplasia—the most clinically significant precursor lesion to colorectal adenocarcinoma—provides an opportunity for timely, minimally invasive intervention to prevent malignant transformation. Here, the development and evaluation of biodegradable near‐infrared fluorescent silica nanoparticles (FSN) that have the potential to improve adenoma detection during fluorescence‐assisted white‐light colonoscopic surveillance in rodent and human‐scale models of colorectal carcinogenesis is described. FSNs are biodegradable (t_1/2 of 2.7 weeks), well‐tolerated, and enable detection and delineation of adenomas as small as 0.5 mm² with high tumor‐to‐background ratios. Furthermore, in the human scale, APC^1311/+ porcine model, the clinical feasibility and benefit of using FSN‐guided detection of colorectal adenomas using video‐rate fluorescence‐assisted white‐light endoscopy is demonstrated. Since nanoparticles of similar size (e.g., 100–150 nm) or composition (i.e., silica and silica/gold hybrid) have already been successfully translated to the clinic, and clinical fluorescent/white‐light endoscopy systems are becoming more readily available, there is a viable path towards clinical translation of the proposed strategy for early colorectal cancer detection and prevention in high‐risk patients.     

Lack of Functional P110δ Affects Expression of Activation Marker CD80 but Does Not Influence Functions of Neutrophils

Neutrophils are specialized immune cells that are essential constituents of the innate immune response. They defend the organism against pathogens through various mechanisms. It was reported that phosphatidylinositols are key players in neutrophil functions, especially in the activity of class-I phosphoinositide 3-kinases (PI3Ks). P110δ, one of the PI3K subunits, is mostly expressed in immune cells, and its activity plays an important role in inflammatory responses. The aim of this study was to investigate the role of p110δ in neutrophil antimicrobial functions, activation status and cytokine production. To this end, we used bone marrow and splenic neutrophils isolated from a murine model expressing catalytically inactive p110δ^D910A/D910A. The level of phagocytosis and degranulation, the expressions of activation markers and cytokine production were determined by flow cytometry. ROS generation and NET release were assessed by fluorometry and fluorescent microscopy. We observed a significantly higher percentage of CD80-positive cells among the splenic granulocytes and found granulocytes subpopulations of differing phenotypes between WT and p110δ^D910A/D910A mice by multiparametric tSNE analysis. Moreover, we detected some differences in the expressions of activation markers, intracellular production of cytokines and bacterial killing. However, we did not observe any alterations in the selected neutrophil functions in p110δ mutant mice. Altogether, our data suggest that the catalytic p110 subunit(s), other than p110δ, is a key player in most neutrophil functions in mice. A follow-up study to correlate these in vitro results with in vivo observations is highly recommended.