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When it is safe to proceed with transplantation after coronavirus disease 2019 (COVID-19) infection is still unknown. We describe the clinical course and management of immunosuppression in a patient with positive real-time polymerase chain reaction (RT-PCR) for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in a nasopharyngeal swab at the time of kidney transplantation, and with positive antibodies for SARS-CoV-2. The patient had no complications and was discharged with a functioning graft. [ABSTRACT FROM AUTHOR]

The article explores the relationship between human trafficking and international adoption from the perspective of international (criminal) law. The article aims to indicate the specific position of international adoptions in relation to human traffic-king. To accomplish this goal, the article provides a review of relevant literature on this subject matter, including the views of authors who examined this relationship, with specific reference to current international documents in the field of human trafficking and international adoptions. The inadequate international documents on this matter and the authors' insufficent commitment to exploring this issue more thoroughly have generated different and often contradictory standpoints, and ultimately resulted in diverse and fairly liberal interpretation of certain international law provisions. The literature review allows us to observe the diversity of those views and the lack of common agreement among the authors, particularly on the basic concepts, which is one of the major hindrances in exploring this relationship. In the end, the author of this article suggest that an adequate solution may be the re-examination and reform of international law in the area of human trafficking and international adoptions, which would entail amending and supplementing the existing provisions or regulating illicit intercountry adoptions in a separate international document.

The problem of establishing an effective solid waste management system is complex and still unresolved in Serbian municipalities, cities and settlements. Most landfills in Serbia do not meet basic sanitary standards and can often contain waste that is dangerous to human, plant and animal health, and waste that can be recycled is often dumped. The aim of this paper is to investigate the relationship between waste generation and private investments in waste management. Statistical method of multiple linear regression was used to examine the impact of three predictors - economic development, investments in waste management, and urban population, on the dependent variable - municipal solid waste generation. The results of the research reveal that investments in waste management in Serbia do not have an effect on the waste reduction because the financial resources for such investments are not adequately managed. There is a large number of scientific researches that have dealt with the analysis of the mentioned relationship, however, their number on the example of Serbia is rather scarce. The results of the research could be useful to the state administrations of the Republic of Serbia.

Photocatalytic degradation of the carbamate insecticide methomyl and its commercial product Lannate-90 in aqueous suspension of TiO2 and ZnO using an Osram ultra-vitalux' lamp (315-400 nm) was investigated. The objective of the investigation was to study and compare the rates of photochemical degradation of the pure active compound and its formulated product in order to find out the impact of inert ingredients on degradation processes. The photochemical degradation of pure methomyl was found to be slower than the degradation of its commercial product Lannate-90. Photodegradation was investigated by UV-Vis spectrometry and HPLC, while mineralization was monitored using IC and TOC analyses. Light absorption capabilities of catalysts were characterized by ultraviolet-visible diffuse reflectance spectroscopy method, while the stability of catalysts was studied by infrared analyses. Degradation products of methomyl and its formulated product were identified by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) results and tentative photodegradation pathways were proposed.

Introduction/Objective. Low bone mineral density (BMD) is commonly associated with alterations of nutritional status. The aims of the present study were to evaluate the prevalence of low BMD and its associated nutritional risk factors in Vojvodina population and to use linear regression equations to predict the BMD by using a simple marker of nutritional status, body mass index (BMI). Methods. In this retrospective, cross-sectional study, the study population included subjects who were undergoing assessment of BMD between January and December 2017, and who have met the study inclusion criteria. A total of 1974 patients (1866 women and 108 men) were included in this analysis of nutritional status according to anthropometry and BMI index, and dual-energy X-ray absorptiometry (DEXA) measurements of BMD of the femoral neck and lumbar spine. The relationship between BMI and BMD was analyzed by linear regression equation. Results. Median age was 63 (56–70) years. Considering nutritional status category, there were 40% overweight, 31% obese and 29% normal weight subjects. In most of the sample, the subjects had low BMD, 37% had osteopenia, and 25% had osteoporosis. In both bone areas we observed trends of lowering BMD as the subjects BMI decreased. Subjects with osteoporosis are more prone to BMI depended BMD changes, concerning subjects with osteopenia and normal BMD. In addition, normal weight subjects compared to overweight and obese had the highest prediction coefficients of BMI-depended changes on BMD. Conclusion. High prevalence of low BMD coexists with overweight and obese elderly females in Vojvodina. Prediction equations for the calculation of BMD can be used to evaluate the effect of BMI changes on BMD in clinical settings.

Nicosulfuron, a sulfonylurea herbicide, was subjected to different Fenton reactions at pH of a nicosulfuron aqueous solution (pH 5). Usually, the optimal pH for the Fenton reaction is between 3 and 4, but the addition of acids is not environmentally acceptable. This is the reason why the reactions were performed at a higher pH value than usual. So, classical Fenton and Fenton-like reactions were applied as well as photo-Fenton and photo-Fenton-like reactions. In addition, microwave Fenton and Fenton-like reactions were used in nicosulfuron degradation. Influences of Fe2+ and Fe3+ concentrations, as well as hydrogen peroxide concentrations, were studied. The Fenton reaction was much faster and more efficient than the Fenton-like reaction, while the photo- Fenton reaction proceeded much faster and more efficiently than the Fenton reaction. The microwave-Fenton and microwave-Fenton-like reactions proceeded with increased efficiency in comparison to the Fenton and Fenton-like reactions. The phytotoxicity and acute toxicity of the reaction products of nicosulfuron oxidation by the photo-Fenton reaction were analyzed. The toxicity testing of nicosulfuron treatment by photo-Fenton process showed a decrease in phytotoxicity, while the acute toxicity tests showed that the samples after treatment had lower toxicity. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172013, Grant no. 172007 and Grant no. III 46008]

Nanocrystalline TiO2, synthesized by sol-gel route and characterized by XRPD, BET and SEM measurements, was applied in the photocatalytic degradation of amoxicillin, using an Osram Ultra-Vitalux® lamp as the light source. Amoxicillin is a semi-synthetic penicillin type antibiotic active against a wide range of grampositive and a limited range of gram-negative organisms. The continuous release of antibiotics and their persistence in the environment may result in serious irreversible effects on aquatic and terrestrial organisms. Heterogeneous catalysis, which uses catalysts like TiO2, is a promising route for the degradation of organic pollutants including antibiotics. The effects of initial concentration of catalyst, initial salt concentration (NaCl and Na2SO4), ethanol and pH on the photocatalytic degradation of amoxicillin were studied. The mineralization of amoxicillin was analyzed by ion chromatography as well as by total organic analysis. The catalytic properties of nanocrystalline TiO2 were compared to Evonik P25 catalyst.

Gamification in marketing can be understood as the use of game mechanisms to motivate customers and encourage them to behave in a specific way and interact in some activities or communities in order to increase their satisfaction, loyalty and commitment, thereby contributing to brand building. There are many foreign works confirming the benefits of gamification. However, there is an absence of any known studies explicitly conducted into gamification within a marketing context in the Slovak Republic. This paper therefore attempts to address this kind of research gap and answer the question of whether gamification is a more effective form of promotion for improving the purchasing behaviour of customers in Slovakia. The results of the research confirm that gamification as part of sales promotion has a positive effect on the purchasing behaviour, search intentions and attitudes of Slovak customers. The results also indicate the positive mediation role of motivation based theory related to gamification and customer purchasing behaviour.

We hypothesized that clinically sized (1-5 mm thick),compact cardiac constructs containing physiologically high density of viable cells (≈108 cells/cm3) can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of per fluorocarbons), or with electrical stimulation (continuous application of biphasic pulses, 2 ms, 5 V, 1 Hz). Tissue constructs cultured without perfusion or electrical stimulation served as controls. Medium perfusion and addition of per fluorocarbons resulted in compact, thick constructs containing physiologic density of viable, electromechanically coupled cells, in contrast to control constructs which had only a≈100 μm thick peripheral region with functionally connected cells. Electrical stimulation of cultured constructs resulted in markedly improved contractile properties, increased amounts of cardiac proteins, and remarkably well developed ultrastructure (similar to that of native heart) as compared to non-stimulated controls. We discuss here the state of the art of cardiac tissue engineering, in light of the biomimetic approach that reproduces in vitro some of the conditions present during normal tissue development.

Due to the increasing consumers' interest for 'healthy' food, it is necessary to include functional ingredients in our food. Tea kombucha mushroom is just one of them. Black tea sweetened with sucrose is most commonly used as a substrate for tea fungus microorganisms. The metabolic activity of kombucha in the milk and obtaining a new fermented diet dairy drink is the subject of these investigations. The aim is to investigate the effect of different concentrations of inoculum kombucha on the quality of the obtained fermented milk products. In the study, the standard microbiological, chemical and sensory methods were used. The low-energy fermented dairy products with 0.9% milk fat were produced by using the concentrated inoculums symbiotic kombucha culture and probiotic yogurt. In the samples produced by the fermentation of kombucha, the content of L-lactic acid was significantly higher than the content of D-lactic acid, and the highest values were recorded in the kombucha capsules (K-0, 12%),with the average of 0.958 g/100g. The metabolic activity of kombucha fermented milk lactose is slower compared with the probiotic culture, but its content is certainly acceptable, and not much higher than the probiotic yogurt. Fermented drinks contain certain amounts of D-glucose and Dfructose, which depend on the origin and amount of inoculum. The sensory quality of fully fermented milk products obtained by the kombucha fermentation indicate that the ethanol content is minute. The resulting product is characterized by high-quality sensory, microbiological and chemical properties.

Competing Interests: Competing interests The author declares no competing interests.

Geometric and structural integrity often deteriorate in 3D printed cell-laden constructs over time due to cellular compaction and hydrogel shrinkage. This study introduces a new approach that synergizes the advantages of cell compatibility of biological hydrogels and mechanical stability of elastomeric polymers for structure fidelity maintenance upon stereolithography and extrusion 3D printing. Enabling this advance is the composite bioink, formulated by integrating elastomeric microparticles from poly(octamethylene maleate (anhydride) citrate) (POMaC) into biologically derived hydrogels (fibrin, gelatin methacryloyl (GelMA), and alginate). The composite bioink enhanced the elasticity and plasticity of the 3D printed constructs, effectively mitigating tissue compaction and swelling. It exhibited a low shear modulus and a rapid crosslinking time, along with a high ultimate compressive strength and resistance to deformation from cellular forces and physical handling; this was attributed to packing and stress dissipation of elastomeric particles, which was confirmed via mathematical modelling. Enhanced functional assembly and stability of human iPSC-derived cardiac tissues and primary vasculature proved the utility of the composite bioink in tissue engineering. In vivo implantation studies revealed that constructs containing POMaC particles exhibited improved resilience against host tissue stress, enhanced angiogenesis, and infiltration of pro-reparative macrophages., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Milica Radisic reports financial support was provided by National Institutes of Health Grant 2R01 HL076485. Milica Radisic reports financial support was provided by Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant (RGPIN 326982-10). Milica Radisic reports financial support was provided by NSERC Strategic Grant (STPGP 506689-17). Milica Radisic reports financial support was provided by Canadian Institutes of Health Research (CIHR) Foundation Grant FDN-167274. Milica Radisic reports financial support was provided by Canada Research Chairs and Killam Fellowship. Shira Landau reports financial support was provided by Rothschild Fellowship. Shira Landau reports financial support was provided by EMBO ALTF 530–2022. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide with numerous inflammatory cell etiologies associated with impaired cardiac function and heart failure. Inflammatory cardiomyopathy, also known as myocarditis, is an acquired cardiomyopathy characterized by inflammatory cell infiltration into the myocardium with a high risk of progression to deteriorated cardiac function. Recently, amidst the ongoing COVID-19 pandemic, the emergence of acute myocarditis as a complication of SARS-CoV-2 has garnered significant concern. Given its mechanisms remain elusive in conjunction with the recent withdrawal of previously FDA-approved antiviral therapeutics and prophylactics due to unexpected cardiotoxicity, there is a pressing need for human-mimetic platforms to investigate disease pathogenesis, model dysfunctional features, and support pre-clinical drug screening. Traditional in vitro models for studying cardiovascular diseases have inherent limitations in recapitulating the complexity of the in vivo microenvironment. Heart-on-a-chip technologies, combining microfabrication, microfluidics, and tissue engineering techniques, have emerged as a promising approach for modeling inflammatory cardiac diseases like myocarditis. This review outlines the established and emerging conditions of inflamed myocardium, identifying key features essential for recapitulating inflamed myocardial structure and functions in heart-on-a-chip models, highlighting recent advancements, including the integration of anisotropic contractile geometry, cardiomyocyte maturity, electromechanical functions, vascularization, circulating immunity, and patient/sex specificity. Finally, we discuss the limitations and future perspectives necessary for the clinical translation of these advanced technologies., Competing Interests: A.P., M.H.C.L., A.S., and R.K. have no conflicts to disclose. M.R. is an inventor on an issued US patent for Biowire technology that is licensed to Valo Health; she receives royalties for this invention., (© 2024 Author(s).)

Competing Interests: Declaration of interests M.R. is an inventor in multiple patents covering Biowire heart-on-a-chip technology that are licensed to Valo Health. She receives royalty from these inventions. M.R. holds equity in and receives consulting fees from Quthero, Inc. She is an inventor on patents and patent applications describing regenerative peptides and biomaterials that have been licensed to Quthero, Inc. D.D.H. is a founder of Vivodyne, Inc., and holds equity in Vivodyne, Inc., and Emulate Bio, Inc. D.D.H. has a number of patent applications and issued patents related to in vitro models of human tissue. M.H. is an inventor on several patents related to organoid work. J.B. is an inventor on a patent related to organoid technology, has received consultation fees, and is principal investigator on an industry-sponsored project related to the work (Proteostasis, Eloxx Pharmaceuticals). He cofounded and has shares <5% in FAIR Therapeutics. Full disclosures can be found at https://www.umcutrecht.nl/en/research/researchers/beekman-jeffrey-jm.

The fabrication of complex and stable vasculature in engineered cardiac tissues represents a significant hurdle towards building physiologically relevant models of the heart. Here, we implemented a 3D model of cardiac vasculogenesis, incorporating endothelial cells (EC), stromal cells, and human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CM) in a fibrin hydrogel. The presence of CMs disrupted vessel formation in 3D tissues, resulting in the upregulation of endothelial activation markers and altered extracellular vesicle (EV) signaling in engineered tissues as determined by the proteomic analysis of culture supernatant. miRNA sequencing of CM- and EC-secreted EVs highlighted key EV-miRNAs that were postulated to play differing roles in cardiac vasculogenesis, including the let-7 family and miR-126-3p in EC-EVs. In the absence of CMs, the supplementation of CM-EVs to EC monolayers attenuated EC migration and proliferation and resulted in shorter and more discontinuous self-assembling vessels when applied to 3D vascular tissues. In contrast, supplementation of EC-EVs to the tissue culture media of 3D vascularized cardiac tissues mitigated some of the deleterious effects of CMs on vascular self-assembly, enhancing the average length and continuity of vessel tubes that formed in the presence of CMs. Direct transfection validated the effects of the key EC-EV miRNAs let-7b-5p and miR-126-3p in improving the maintenance of continuous vascular networks. EC-EV supplementation to biofabricated cardiac tissues and microfluidic devices resulted in tissue vascularization, illustrating the use of this approach in the engineering of enhanced, perfusable, microfluidic models of the myocardium., (Creative Commons Attribution license.)

The intricate anatomical structure and high cellular density of the myocardium complicate the bioengineering of perfusable vascular networks within cardiac tissues. In vivo neonatal studies highlight the key role of resident cardiac macrophages in post-injury regeneration and angiogenesis. Here, we integrate human pluripotent stem-cell-derived primitive yolk-sac-like macrophages within vascularized heart-on-chip platforms. Macrophage incorporation profoundly impacted the functionality and perfusability of microvascularized cardiac tissues up to 2 weeks of culture. Macrophages mitigated tissue cytotoxicity and the release of cell-free mitochondrial DNA (mtDNA), while upregulating the secretion of pro-angiogenic, matrix remodeling, and cardioprotective cytokines. Bulk RNA sequencing (RNA-seq) revealed an upregulation of cardiac maturation and angiogenesis genes. Further, single-nuclei RNA sequencing (snRNA-seq) and secretome data suggest that macrophages may prime stromal cells for vascular development by inducing insulin like growth factor binding protein 7 (IGFBP7) and hepatocyte growth factor (HGF) expression. Our results underscore the vital role of primitive macrophages in the long-term vascularization of cardiac tissues, offering insights for therapy and advancing heart-on-a-chip technologies., Competing Interests: Declaration of interests M.R. and Y.Z. are inventors on an issued patent that describes Biowire technology. This patent is licensed to Valo Health. M.R. and Y.Z. receive licensing revenue., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Epicardial cells (EPIs) form the outer layer of the heart and play an important role in development and disease. Current heart-on-a-chip platforms still do not fully mimic the native cardiac environment due to the absence of relevant cell types, such as EPIs. Here, using the Biowire II platform, engineered cardiac tissues with an epicardial outer layer and inner myocardial structure are constructed, and an image analysis approach is developed to track the EPI cell migration in a beating myocardial environment. Functional properties of EPI cardiac tissues improve over two weeks in culture. In conditions mimicking ischemia reperfusion injury (IRI), the EPI cardiac tissues experience less cell death and a lower impact on functional properties. EPI cell coverage is significantly reduced and more diffuse under normoxic conditions compared to the post-IRI conditions. Upon IRI, migration of EPI cells into the cardiac tissue interior is observed, with contributions to alpha smooth muscle actin positive cell population. Altogether, a novel heart-on-a-chip model is designed to incorporate EPIs through a formation process that mimics cardiac development, and this work demonstrates that EPI cardiac tissues respond to injury differently than epicardium-free controls, highlighting the importance of including EPIs in heart-on-a-chip constructs that aim to accurately mimic the cardiac environment., (© 2024 The Authors. Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

Biofabrication technologies hold the potential to provide high-throughput, easy-to-operate, and cost-effective systems that recapitulate complexities of the native heart. The size of the fabricated model, printing resolution, biocompatibility, and ease-of-fabrication are some of the major parameters that can be improved to develop more sophisticated cardiac models. Here, we review recent cardiac engineering technologies ranging from microscaled organoids, millimeter-scaled heart-on-a-chip platforms, in vitro ventricle models sized to the fetal heart, larger cardiac patches seeded with billions of cells, and associated biofabrication technologies used to produce these models. Finally, advancements that facilitate model translation are discussed, such as their application as carriers for bioactive components and cells in vivo or their capability for drug testing and disease modeling in vitro., Competing Interests: Declaration of Competing Interest Editorial declaration: M.R. is an Associate Editor of ACS Biomaterial Science & Engineering, Reviewing Editor for eLife, Consulting Editor for Journal of Molecular and Cellular Cardiology, Editorial Board of Tissue Engineering, Advanced Drug Delivery, Advanced Biosystems and Regenerative Biomaterials and was not involved in the editorial review or the decision to publish this article. The authors declare the following financial interests/personal relationships, which may be considered as potential competing interests: M.R. and Y.Z. are inventors on an issued US patent for Biowire technology that is licensed to Valo Health; they receive royalties for this invention. M.R. is supported by the Killam Fellowship and is a Canada Research Chair. S.O. is supported by a CIHR Canada Graduate Scholarship. Y.Z. and R.K. are supported by a CIHR Postdoctoral Fellowship., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Adverse cardiac outcomes in COVID-19 patients, particularly those with preexisting cardiac disease, motivate the development of human cell-based organ-on-a-chip models to recapitulate cardiac injury and dysfunction and for screening of cardioprotective therapeutics. Here, we developed a heart-on-a-chip model to study the pathogenesis of SARS-CoV-2 in healthy myocardium established from human induced pluripotent stem cell (iPSC)-derived cardiomyocytes and a cardiac dysfunction model, mimicking aspects of preexisting hypertensive disease induced by angiotensin II (Ang II). We recapitulated cytopathic features of SARS-CoV-2-induced cardiac damage, including progressively impaired contractile function and calcium handling, apoptosis, and sarcomere disarray. SARS-CoV-2 presence in Ang II-treated hearts-on-a-chip decreased contractile force with earlier onset of contractile dysfunction and profoundly enhanced inflammatory cytokines compared to SARS-CoV-2 alone. Toward the development of potential therapeutics, we evaluated the cardioprotective effects of extracellular vesicles (EVs) from human iPSC which alleviated the impairment of contractile force, decreased apoptosis, reduced the disruption of sarcomeric proteins, and enhanced beta-oxidation gene expression. Viral load was not affected by either Ang II or EV treatment. We identified MicroRNAs miR-20a-5p and miR-19a-3p as potential mediators of cardioprotective effects of these EVs., Competing Interests: Competing interests statement:Y.Z., G.V.-N., B.Z., and M.R. are inventors on patents for cardiac tissue cultivation that are licensed to Valo Health. Q.W., Y.Z., and M.R. have a filed patent application on thermoplastic polymer composition for micro 3D printing and uses thereof. B.Z. holds equity in OrganoBiotech.