Publications by authors named "Zeilinger K"

Beneficial effects of pro- and prebiotics in weanling piglets are of great interest in livestock production. Similarly, the use of specific vaccines is of interest as alternative to antibiotics to reduce postweaning performance losses. The aim of this study was the assessment of the effect of a dual-strain probiotic ( and ) and a prebiotic (fructo-oligosaccharides) as well as the additional vaccination with an autogenous inactivated vaccine on the performance of newly weaned piglets after experimental infection with an enterotoxigenic Forty piglets at the age of 28 d were randomly allotted to one of five groups: nonchallenged control (NC); challenged positive control (PC); challenged and vaccinated (CV); challenged and diet supplemented with pre- and probiotic mix (CM) and challenged, diet supplemented with pro- and prebiotic mix and vaccinated (CMV).

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A novel rapid assay was developed as part of a concept to determine potential tailor-made combinations of pre- and probiotics for individual farms. Sow faecal slurries from 20 German pig farms were anaerobically incubated with pre- and probiotics or their combinations together with pathogenic strains that are of interest in pig production. Aliquots of these slurries were then incubated with media containing antibiotic mixtures allowing only growth of the specific pathogen.

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Objective: For optimized expansion of human-induced pluripotent stem cells (hiPSCs) with regards to clinical applications, we investigated the influence of the inoculum density on the expansion procedure in 3D hollow-fibre bioreactors.

Materials And Methods: Analytical-scale bioreactors with a cell compartment volume of 3 mL or a large-scale bioreactor with a cell compartment volume of 17 mL were used and inoculated with either 10 × 10 or 50 × 10 hiPSCs. Cells were cultured in bioreactors over 15 days; daily measurements of biochemical parameters were performed.

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Background: Remimazolam is an ultra-short acting benzodiazepine under development for procedural sedation and general anesthesia. It is hydrolyzed by CES1 to an inactive metabolite (CNS7054).

Purpose: In this study, the effect of continuous remimazolam exposure on its metabolism and on expression was investigated in a dynamic 3-D bioreactor culture model inoculated with primary human hepatocytes.

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For clinical and/or pharmaceutical use of human-induced pluripotent stem cells (hiPSCs), large cell quantities of high quality are demanded. Therefore, we combined the expansion of hiPSCs in closed, perfusion-based 3D bioreactors with noninvasive online monitoring of oxygen as culture control mechanism. Bioreactors with a cell compartment volume of 3 or 17 ml were inoculated with either 10 × 10 or 50 × 10 cells, and cells were expanded over 15 days with online oxygen and offline glucose and lactate measurements being performed.

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Objectives: To determine the most efficient design of a hollow fiber-based bioreactor device for a bioartificial liver support system through comparative bioengineering evaluations.

Results: We compared two types of hollow fiber-based bioreactors, the interwoven-type bioreactor (IWBAL) and the dialyzer-type bioreactor (DBAL), by evaluating the overall mass transfer coefficient (K) and the convective coefficient (X). The creatinine and albumin mass transfer coefficients and convective coefficients were calculated using our mathematical model based on the homoporous theory and the modified Powell method.

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The accurate prediction of hepatotoxicity demands validated human in vitro models that can close the gap between preclinical animal studies and clinical trials. In this study we investigated the response of primary human liver cells to toxic drug exposure in a perfused microscale 3D liver bioreactor. The cellularized bioreactors were treated with 5, 10, or 30 mM acetaminophen (APAP) used as a reference substance.

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Human induced pluripotent stem cells (hiPSCs) are a promising source from which to derive distinct somatic cell types for in vitro or clinical use. Existent protocols for hepatic differentiation of hiPSCs are primarily based on 2D cultivation of the cells. In the present study, the authors investigated the generation of hiPSC-derived hepatocyte-like cells using two different 3D culture systems: A 3D scaffold-free microspheroid culture system and a 3D hollow-fiber perfusion bioreactor.

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The derivation of hepatocytes from human induced pluripotent stem cells (hiPSC) is of great interest for applications in pharmacological research. However, full maturation of hiPSC-derived hepatocytes has not yet been achieved in vitro. To improve hepatic differentiation, co-cultivation of hiPSC with human umbilical vein endothelial cells (HUVEC) during hepatic differentiation was investigated in this study.

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Human embryonic stem cells (hESCs) are pluripotent stem cells that offer a wide range of applications in regenerative medicine. In addition, they have been proposed as an appropriate alternative source of hepatocytes. In this work, hESCs were differentiated into definitive endodermal cells (DECs), followed by maturation into hepatocyte-like cells (HLCs).

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Article Synopsis
  • The study focused on the liver's response to varying concentrations of ethanol, highlighting that the liver is a primary site of alcohol toxicity.
  • Primary human liver cells were cultured in a specialized device to simulate natural liver conditions and were exposed to three different ethanol concentrations (150 mM, 300 mM, and 600 mM) for analysis.
  • Results showed that as the ethanol concentration increased, the number of differentially expressed genes also increased, revealing that low to medium concentrations triggered adaptive responses while high concentrations indicated cellular damage.
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The hepatic differentiation of human induced pluripotent stem cells (hiPSC) holds great potential for application in regenerative medicine, pharmacological drug screening, and toxicity testing. However, full maturation of hiPSC into functional hepatocytes has not yet been achieved. In this study, we investigated the potential of a dynamic three-dimensional (3D) hollow fiber membrane bioreactor technology to improve the hepatic differentiation of hiPSC in comparison to static two-dimensional (2D) cultures.

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3D cultures of human stem cell-derived hepatocyte-like cells (HLCs) have emerged as promising models for short- and long-term maintenance of hepatocyte phenotype in vitro cultures by better resembling the in vivo environment of the liver and consequently increase the translational value of the resulting data. In this study, the first stage of hepatic differentiation of human neonatal mesenchymal stem cells (hnMSCs) was performed in 2D monolayer cultures for 17 days. The second stage was performed by either maintaining cells in 2D cultures for an extra 10 days, as control, or alternatively cultured in 3D as self-assembled spheroids or in multicompartment membrane bioreactor system.

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In vitro liver cell culture models are gaining increasing importance in pharmacological and toxicological research. The source of cells used is critical for the relevance and the predictive value of such models. Primary human hepatocytes (PHH) are currently considered to be the gold standard for hepatic in vitro culture models, since they directly reflect the specific metabolism and functionality of the human liver; however, the scarcity and difficult logistics of PHH have driven researchers to explore alternative cell sources, including liver cell lines and pluripotent stem cells.

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Primary human hepatocytes (PHH) are still considered as gold standard for investigation of in vitro metabolism and hepatotoxicity in pharmaceutical research. It has been shown that the three-dimensional (3D) cultivation of PHH in a sandwich configuration between two layers of extracellular matrix (ECM) enables the hepatocytes to adhere three dimensionally leading to formation of in vivo like cell-cell contacts and cell-matrix interactions. The aim of the present study was to investigate the influence of different ECM compositions on morphology, cellular arrangement and bile canaliculi formation as well as bile excretion processes in PHH sandwich cultures systematically.

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Accurate prediction of the potential hepatotoxic nature of new pharmaceuticals remains highly challenging. Therefore, novel in vitro models with improved external validity are needed to investigate hepatic metabolism and timely identify any toxicity of drugs in humans. In this study, we examined the effects of diclofenac, as a model substance with a known risk of hepatotoxicity in vivo, in a dynamic multi-compartment bioreactor using primary human liver cells.

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Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic Stellate cells (HSC). Two-dimensional (2D) culture of primary human hepatocyte (PHH) is still considered as the "gold standard" for in vitro testing of drug metabolism and hepatotoxicity. It is well-known that the 2D monoculture of PHH suffers from dedifferentiation and loss of function.

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The rat pancreatic progenitor cell line B-13 is of interest for research on drug metabolism and toxicity since the cells trans-differentiate into functional hepatocyte-like cells (B-13/H) when treated with glucocorticoids. In this study we investigated the trans-differentiation and liver-specific functions of B-13/H cells in a three-dimensional (3D) multi-compartment bioreactor, which has already been successfully used for primary liver cell culture. Undifferentiated B-13 cells were inoculated into the bioreactor system and exposed to dexamethasone to promote hepatic trans-differentiation (B-13/HT).

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Drug induced liver injury (DILI) is an idiosyncratic adverse drug reaction leading to severe liver damage. Kupffer cells (KC) sense hepatic tissue stress/damage and therefore could be a tool for the estimation of consequent effects associated with DILI. Aim of the present study was to establish a human in vitro liver model for the investigation of immune-mediated signaling in the pathogenesis of DILI.

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Different types of stem cells have been investigated for applications in drug screening and toxicity testing. In order to provide sufficient numbers of cells for such in vitro applications a scale-up of stem cell culture is necessary. Bioreactors for dynamic three-dimensional (3D) culture of growing cells offer the option for culturing large amounts of stem cells at high densities in a closed system.

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Article Synopsis
  • Aging makes cells in the body, including the liver, less effective at dealing with injuries and stress over time.
  • In older rats, certain antioxidants were found to increase, while others decreased, showing that the way the liver responds to stress changes with age.
  • The study also found that a specific signaling pathway in the liver becomes more active in older rats, which might help liver cells grow and heal when needed.
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Investigation: A novel active wound dressing (AWD) concept based on a microporous hollow fiber membrane network was investigated in an animal model. It provides a local solution-perfused environment for regenerative cell nutrition, wound irrigation, debris removal, electrolyte balancing, pH regulation, and topical antibiosis. The device is capable of supplying soluble factors, as tested experimentally for the recombinant human growth and differentiation factor-5 (rhGDF-5).

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Primary human hepatocytes (PHH) are considered to be the gold standard for in vitro testing of xenobiotic metabolism and hepatotoxicity. However, PHH cultivation in 2D mono-cultures leads to dedifferentiation and a loss of function. It is well known that hepatic non-parenchymal cells (NPC), such as Kupffer cells (KC), liver endothelial cells (LEC), and hepatic stellate cells (HSC), play a central role in the maintenance of PHH functions.

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Integrated approaches using different in vitro methods in combination with bioinformatics can (i) increase the success rate and speed of drug development; (ii) improve the accuracy of toxicological risk assessment; and (iii) increase our understanding of disease. Three-dimensional (3D) cell culture models are important building blocks of this strategy which has emerged during the last years. The majority of these models are organotypic, i.

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Primary human hepatocytes (PHH) are the "gold standard" for in vitro toxicity tests. However, 2D PHH cultures have limitations that are due to a time-dependent dedifferentiation process visible by morphological changes closely connected to a decline of albumin production and CYP450 activity. The 3D in vitro culture corresponds to in vivo-like tissue architecture, which preserves functional characteristics of hepatocytes, and therefore can at least partially overcome the restrictions of 2D cultures.

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