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The aim of these in vitro studies was to determine and compare the mechanical and tribological performance of two commercially available thermoplastic materials, namely BioHPP and Biocetal, used in dental prosthetics. In order to perform the comparative tests of both materials, the dog-bone shaped samples were formed by an injection molding process as in standard polymer materials research, wherein Biocetal samples constituted the research group, and BioHPP samples served as a control group. In the presented studies, their mechanical parameters were reported and analyzed: namely, Shore's hardness, unnotched impact strength, tensile strength, flexural strength, as well as abrasive wear resistance, obtained within appropriate tribological and mechanical tests. The Shapiro–Wilk test, Q–Q plot analysis, Grubbs test and Student's t-test (p < 0.05) were used to statistically evaluate the results. The experimental results revealed that BioHPP material is characterized by higher hardness, impact strength, bending strength, and also lower "wet" abrasion wear if compared to Biocetal performance. However, it is subject to higher abrasive wear under "dry" conditions and reveals higher stiffness as well as lower ability to deform, which could affect a patient's comfort during application. BioHPP, despite being a high-performance polymer material, also has some drawbacks that may affect the poorer long-term use of dentures in people producing less saliva. [ABSTRACT FROM AUTHOR]

The natural aging process of the human organism leads to both physiological and pathological changes, including tooth loss. This requires dental prosthetic interventions aimed at restoring patients' quality of life. The use of such prostheses necessitates selection of sufficiently strong, aesthetic and biocompatible materials, which also offer ease of shaping. The market for materials used in prosthetic applications offers a wide array of options; however, selection of the most suitable material for specific clinical scenarios can be challenging for dental professionals. This paper continues the comprehensive investigation of the physiochemical and mechanical/functional properties of two commonly used prosthetic—Biocetal and BioHPP—offering a comparative analysis of their characteristics to provide valuable insights for dentists and prosthodontists. The study focuses on in vitro analyses of physiochemical parameters, including density, water sorption, contact angle, and surface roughness. The structure of the materials was examined via scanning electron microscopy. Additionally, microbiological studies were performed using strains of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Statistical analysis was performed using Shapiro–Wilk test, Q-Q plot analysis, Grubbs test, and Student's T-test (p < 0.05). The findings indicate that BioHPP demonstrates superior physiochemical and microbiological properties. However, Biocetal exhibit better surface characteristics. Despite its high performance, BioHPP presents certain drawbacks, which may influence dentists' material choice in specific clinical cases, particularly for certain prosthetic restorations. [ABSTRACT FROM AUTHOR]

Purpose: While progress has been made in the realm of teaching about sustainability to business students, integrating sustainability into experiential learning with a systemic mindset has been identified by leading scholars as an area for improvement. The purpose of this paper is to describe a pilot project in which students prepared a sustainability report for a client company and to answer the question of whether the experiment yielded the anticipated benefits. Design/methodology/approach: The paper presents an initiative that was part of an MBA course delivered at the Warsaw University of Life Sciences in Poland by an international team of professors. The multinational group of students was confronted with the task of preparing an integrated sustainability report for a large corporation. Findings: The initiative creates opportunities for both students and commercial organizations to understand large business commercial activities from a sustainability perspective. This paper identifies the next steps for others to build upon. Originality/value: The paper explains the experiential learning opportunity that was created, describes how students rose to meet the challenge, discusses the benefits that accrued to students, professors and a commercial organization and shares some guidance for those seeking to emulate this practice.

Background: Lipoprotein X (LpX) is an abnormal lipoprotein fraction, which can be detected in patients with severe hypercholesterolaemia and cholestatic liver disease. LpX is composed largely of phospholipid and free cholesterol, with small amounts of triglyceride, cholesteryl ester and protein. There are no widely available methods for direct measurement of LpX in routine laboratory practice. We present the heterogeneity of clinical and laboratory manifestations of the presence of LpX, a phenomenon which hinders LpX detection. Methods: The study was conducted on a 26-year-old female after liver transplantation (LTx) with severely elevated total cholesterol (TC) of 38 mmol/L and increased cholestatic liver enzymes. TC, free cholesterol (FC), cholesteryl esters (CE), triglycerides, phospholipids, HDL-C, LDL-C, and apolipoproteins AI and B were measured. TC/apoB and FC:CE ratios were calculated. Lipoprotein electrophoresis was performed using a commercially available kit and laboratory-prepared agarose gel. Results: Commercially available electrophoresis failed to demonstrate the presence of LpX. Laboratory-prepared gel clearly revealed the presence of lipoproteins with g mobility, characteristic of LpX. The TC/apoB ratio was elevated and the CE level was reduced, confirming the presence of LpX. Regular lipoprotein apheresis was applied as the method of choice in LpX disease and a bridge to reLTx due to chronic liver insufficiency. Conclusions: The detection of LpX is crucial as it may influence the method of treatment. As routinely available biochemical laboratory tests do not always indicate the presence of LpX, in severe hypercholesterolaemia with cholestasis, any discrepancy between electrophoresis and biochemical tests should raise suspicions of LpX disease.

Objective: It is not currently possible to predict long‐term functional dependency in patients with disorders of consciousness (DoC) after traumatic brain injury (TBI). Our objective was to fit and externally validate a prediction model for 1‐year dependency in patients with DoC ≥2 weeks after TBI. Methods: We included adults with TBI enrolled in TBI Model Systems (TBI‐MS) or Transforming Research and Clinical Knowledge in TBI (TRACK‐TBI) studies who were not following commands at rehabilitation admission or 2 weeks post‐injury, respectively. We fit a logistic regression model in TBI‐MS and validated it in TRACK‐TBI. The primary outcome was death or dependency at 1 year post‐injury, defined using the Disability Rating Scale. Results: In the TBI‐MS Discovery Sample, 1,960 participants (mean age 40 [18] years, 76% male, 68% white) met inclusion criteria, and 406 (27%) were dependent 1 year post‐injury. In a TBI‐MS held out cohort, the dependency prediction model's area under the receiver operating characteristic curve was 0.79 (95% CI 0.74–0.85), positive predictive value was 53% and negative predictive value was 86%. In the TRACK‐TBI external validation (n = 124, age 40 [16] years, 77% male, 81% white), the area under the receiver operating characteristic curve was 0.66 (0.53, 0.79), equivalent to the standard IMPACTcore + CT score (p = 0.8). Interpretation: We developed a 1‐year dependency prediction model using the largest existing cohort of patients with DoC after TBI. The sensitivity and negative predictive values were greater than specificity and positive predictive values. Accuracy was diminished in an external sample, but equivalent to the IMPACT model. Further research is needed to improve dependency prediction in patients with DoC after TBI. ANN NEUROL 2023;94:1008–1023 [ABSTRACT FROM AUTHOR]

Patients with non-large vessel occlusion acute ischemic stroke (NL-AIS) on oral anticoagulants (OAC) constitute the biggest portion among those who cannot receive any potential-reperfusion treatment even if they appear early in the hospital. We present the first case of therapy for NL-AIS in a patient with active anti-Xa anticoagulation, combining andexanet alfa and rtPA, who was recruited for STRoke On AntiCoagulants for Thrombolysis (acronym: STROACT), an ongoing therapeutic trial for non-LVO ischemic stroke on a DOAC. This is also the first report of the use of andexanet alfa-rtPA for AIS in a patient on rivaroxaban, which is the most frequently used non-vitamin K antagonist oral anticoagulant. The patient received the intravenous bolus of 800 mg of andexanet (contralateral arm), followed by a bolus of rtPA (10% of the calculated dose; ipsilateral arm), then a continuous infusion of andexanet at 8 mg/min for 120 min (contralateral arm), and rtPA (90% of the calculated dose; ipsilateral arm)—both stopped after completion of 38.9 and 74% of infusion dose, respectively, due to the severe adverse event related to the administration of rtPA. In this schema, both infusions are ongoing concurrently for approximately 60 min, and then andexanet is administered alone until the completion of the dose (altogether lasting approximately 3 h). The therapy was spectacularly e [ABSTRACT FROM AUTHOR]

This article examines the promotion and adoption of action research as an instrument of institutional change by academic staff in a Brazilian rural university. The results of the research are presented showing the mobilisation of a group of volunteers, the implementation of their action research projects and the sustainability of the process. Particular attention is drawn to the significance of an insider change agent/facilitator as the initiator of the action research process and how his role became superfluous as the networks evolved into true communities of practice. On reflection the original composite daisy model of Melrose and Reid has been discarded in favour of a simpler buttercup-type flower model of analysis to describe the process. (Contains 2 tables and 5 figures.)

Introduction: Some modern acrylic denture base resin enhancing materials, investigated by researchers aiming to improve the properties of the resin, were collected and described as part of this review. Poly(methyl methacrylate) (PMMA), is widely used as a prosthodontic base for both partial and complete dentures, but it has many disadvantages such as low strength, insufficient resistance to fatigue, and porosity. Therefore, the topic of modern thermoplastic materials that could replace acrylic dentures will also be discussed. Materials and methods: In this article, we reviewed literature available on PubMed, Google Scholar, and NIH. The search was conducted in such electronic databases with the following keywords: "acrylic resin", "nanoparticles", "reinforcements of removable dentures", "BioHPP in dentistry", and "acetal resin in dentistry". This study is focused on the effects of adding fibers, fillers, and nanofillers on the properties of PMMA. The paper draws on science-based reviews, original scientific be added to acrylic resin for dental prostheses. Adding carbon nanotubes, titanium dioxide (TiO2), silicon dioxide (SiO2), and zirconium dioxide (ZrO2) can improve the strength and other properties of the resin. Glass fibers, polyamide, aramid, polyethylene, and polypropylene fibers can increase fracture resistance, impact strength, and modulus. Combining ZrO2, zirconium nanotubes, and silane-treated ZrO2 nanoparticles is suggested to be the best solution for reinforcing dental prostheses. Conclusion: The properties of PMMA denture base material can be enhanced with the addition of fibers, fillers, silanized nanoparticles, and hybrid reinforcements to reduce damage and cracks. Due to the lack of an ideal material for dentures, the properties of PMMA can be improved with these modifications to make it significantly more convenient for patients to use. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most aggressive and lethal form of brain tumor. Extracellular vesicles (EVs) released by tumor cells play a critical role in cellular communication in the tumor microenvironment promoting tumor progression and invasion. We hypothesized that GBM EVs possess unique characteristics which exert effects on endogenous CNS cells including neurons, producing dose-dependent neuronal cytotoxicity. We purified EVs from the plasma of 20 GBM patients, 20 meningioma patients, and 21 healthy controls, and characterized EV phenotypes by electron microscopy, nanoparticle tracking analysis, protein concentration, and proteomics. We evaluated GBM EV functions by determining their cytotoxicity in primary neurons and the neuroblastoma cell line SH-SY5Y. In addition, we determined levels of IgG antibodies in the plasma in GBM (n = 82), MMA (n = 83), and controls (non-tumor CNS disorders and healthy donors, n = 50) with capture ELISA. We discovered that GBM plasma EVs are smaller in size and had no relationship between size and concentration. Importantly, GBM EVs purified from both plasma and tumor cell lines produced IgG-mediated, complement-dependent apoptosis and necrosis in primary human neurons, mouse brain slices, and neuroblastoma cells. The unique phenotype of GBM EVs may contribute to its neuronal cytotoxicity, providing insight into its role in tumor pathogenesis. [ABSTRACT FROM AUTHOR]