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Widespread application of islet transplantation as a cure for type 1 Diabetes Mellitus patients is limited mainly due to the need for life-long immunosuppression associated with serious side effects. Immunoisolation by encapsulation of islets in semi-permeable membranes may overcome this issue as it allows for transplantation potentially obviating the need for immunosuppressive drug therapy. This work focuses on the development and validation of a model of the mass transfer and secretion kinetics of insulin – the major regulator of glucose homeostasis – in a new microwell membrane based encapsulation device for pancreatic islets. Due to the high number and complexity of parameters that determine the effectiveness of the device, the implementation of a reliable numerical model is of critical importance for optimization of the micro-confined bioengineered environment. The simultaneous solution of mass transfer and uptake/production reactions occurring through the polymeric membrane system and within the islets allows detailed description of the spatial distribution profiles of insulin, glucose, and oxygen with the aim to assure an adequate insulin dynamics. The simulation tool, experimentally validated, is used to improve the scaffold geometry with the aim to assure adequate responsiveness and function over time for future clinical implementation of the device.

Islet encapsulation in membrane-based devices could allow for transplantation of donor islet tissue in the absence of immunosuppression. To achieve long-term survival of islets, the device should allow rapid exchange of essential nutrients and be vascularized to guarantee continued support of islet function. Recently, we have proposed a membrane-based macroencapsulation device consisting of a microwell membrane for islet separation covered by a micropatterned membrane lid. The device can prevent islet aggregation and support functional islet survival in vitro. Here, based on previous modeling studies, we develop an improved device with smaller microwell dimensions, decreased spacing between the microwells and reduced membrane thickness and investigate its performance in vitro and in vivo. This improved device allows for encapsulating higher islet numbers without islet aggregation and by applying an in vivo imaging system we demonstrate very good perfusion of the device when implanted intraperitoneally in mice. Besides, when it is implanted subcutaneously in mice, islet viability is maintained and a vascular network in close proximity to the device is developed. All these important findings demonstrate the potential of this device for islet transplantation.

Modern technical environments require a high degree of reliability both in machinery and in equipment. Technological progress has, on the one hand, increased this efficiency but on the other hand, it has changed the way in which this equipment and these machines have traditionally been maintained. The authors have set the following assumptions. In order to survive in the market and develop, modern production enterprises realize the assumptions of Industry 4.0, wherein the optimization of maintenance processes is important because of the financial situation. This includes the profits made by the production company and differs from traditional maintenance, by shifting towards new trends such as predictive maintenance; as such, it is crucial for the development of the company. The article is devoted to the most modern predictive maintenance strategy, in the maintenance department of a manufacturing company. The publication describes the meaning of the method, its potential and the theory of action.

Macroencapsulation of islets of Langerhans is a promising strategy for transplantation of insulin-producing cells in the absence of immunosuppression to treat type 1 diabetes. Hollow fiber membranes are of interest there because they offer a large surface-to-volume ratio and can potentially be retrieved or refilled. However, current available fibers have limitations in exchange of nutrients, oxygen, and delivery of insulin potentially impacting graft survival. Here, multibore hollow fibers for islets encapsulation are designed and tested. They consist of seven bores and are prepared using nondegradable polymers with high mechanical stability and low cell adhesion properties. Human islets encapsulated there have a glucose induced insulin response (GIIS) similar to nonencapsulated islets. During 7 d of cell culture in vitro, the GIIS increases with graded doses of islets demonstrating the suitability of the microenvironment for islet survival. Moreover, first implantation studies in mice demonstrate device material biocompatibility with minimal tissue responses. Besides, formation of new blood vessels close to the implanted device is observed, an important requirement for maintaining islet viability and fast exchange of glucose and insulin. The results indicate that the developed fibers have high islet bearing capacity and can potentially be applied for a clinically applicable bioartificial pancreas.

The aim of the study was to analyze the distribution of the main groups of parasitic helminths within the small intestine of the red fox on the example of animals coming from eastern Poland. Two hundred and sixteen red foxes shot in eastern Poland were used in the investigation. Before examination, each small intestine was divided into three equal parts: anterior (A), middle (M), and posterior (P). Each part was examined separately with the sedimentation and counting technique. Six different types of intestinal parasites were detected: Alaria alata (78.7%), Mesocestoides spp. (78.2%), hookworms (72.7%), Taenia spp. (53.2%), Toxocara/Toxascaris (43.1%), and Echinococcus multilocularis (18.5%). Alaria alata was most often found in A and in the only-A variant. Taenia spp. and Toxocara/Toxascaris occurred often in A and were the second (after A. alata) parasites in terms of frequency occurring in the only-A variant. Mesocestoides spp. was most commonly located in M. Parasites with predilection sites located mainly in M and P were E. multilocularis and hookworms. In all parasite species, the variant covering the entire intestine (A + M + P) was found in samples with a higher intensity compared to variants limited to one or two fragments. Our investigation, as one of the few of its type, conducted a comprehensive analysis of the distribution of intestinal helminths in the small intestine of the red fox. It showed significant differences in the distribution of parasitic helminths in the small intestine of the red fox. Determining typical predilection sites for parasites in the intestine can be helpful in creating effective diagnostic methods.

Introduction: Encapsulation of pancreatic islets or beta cells is a promising strategy for treatment of type 1 diabetes by providing an immune isolated environment and allowing for transplantation in a different location than the liver. However, islets used for encapsulation often show lower functionality due to the damaging of islet endothelial cells during the isolation procedure. Factors produced by endothelial cells have great impact on beta cell insulin secretion. Therefore, mutual signaling between endothelial cells and beta cells should be considered for the development of encapsulation systems to achieve high insulin secretion and maintain beta cell viability. Here, we investigate whether co-culture of beta cells with endothelial cells could improve beta cell function within encapsulation devices. Materials and methods: Mouse insulinoma MIN6 cells and human umbilical vein endothelial cells were used for creating composite aggregates on agarose microwell platform. The composite aggregates were encapsulated within flat poly(ether sulfone)/polyvinylpyrrolidone device. Their functionality was assessed by glucose-induced insulin secretion test and compared to non-encapsulated free-floating aggregates. Results: We created composite aggregates of 80–100 µm in diameter, closely mimicking pancreatic islets. Upon glucose stimulation, their insulin secretion is improved in comparison to aggregates consisting of only MIN6 cells. Moreover, the composite aggregates encapsulated within a device secrete more insulin than aggregates consisting of only MIN6 cells. Conclusion: Composite aggregates of MIN6 cells with human umbilical vein endothelial cells have improved insulin secretion in comparison to MIN6 aggregates showing that the interaction of beta cell and endothelial cell is crucial for a functional encapsulation system.

Contains fulltext : 215778.pdf (Publisher’s version ) (Closed access) Intestinal enterocytes are key players in the absorption of magnesium (Mg(2+)) and calcium (Ca(2+)). Understanding the exact molecular mechanisms by which their absorption behavior is regulated could greatly improve treatment strategies for stimulating intestinal absorption in diseases with Mg(2+) and/or Ca(2+) deficiency. However, such studies are hampered by the lack of in vitro intestinal cell models mimicking the mechanical and physiological properties of the gut. In this study we develop an in vitro gut model based on porous micropatterned membranes with villi-like surface topography and mechanical properties closely mimicking that of intestinal tissue. These membranes are prepared via phase separation micromolding using poly-epsilon-caprolactone/poly-lactic-glycolic acid (PCL/PLGA) polymer blend and can facilitate cellular differentiation of Caco-2 cells similar to native enterocytes. In fact, cells cultured on these micropatterned membranes form a brush border of microvilli with spatial differences in morphology and tight junction formation along the villous-base axis. Moreover, cells cultured on our membranes show a 2-fold increased alkaline phosphatase activity at the end of differentiation. Finally, we demonstrate that cells cultured on our micropatterned membranes have a 4- and 1.5-fold increased uptake of (25)Mg and (45)Ca, respectively, compared to non-patterned membranes. These results indicate that the new membranes can mimic the intestinal environment and therefore can have a great impact on mineral uptake in vitro. STATEMENT OF SIGNIFICANCE: This study presents the development of an in vitro gut model consisting of villi-like PCL/PLGA micropatterned membranes. These membranes are prepared via phase separation micromolding (PSmuM), a technique which allows tailoring of the membrane surface topography combined with membrane porosity and interconnectivity which are important parameters for membranes used for in vitro transport studies. The culture of Caco-2 cells on these micropatterned membranes shows that they facilitate cellular differentiation similar to gut enterocytes. Our data indicate that mimicking the 3D geometry of the gut is very important for improving the physiological relevance of in vitro gut models. In the future, our micropatterned membranes with segment-specific geometries, in combination with isotopic measurements, would be applied to perform detailed ion uptake and transport studies. 01 november 2019

Building teams has a fundamental impact for execution of research and development projects. The teams appointed for the needs of given projects are based on individuals from both inside and outside of the organization. Knowledge is not only a product available on the market but also an intangible resource affecting their internal and external processes. Thus it is vitally important for businesses and scientific research facilities to effectively manage knowledge within project teams. The article presents a proposal to use Fuzzy AHP (Analytic Hierarchy Process ) and ANFIS (Adaptive Neuro Fuzzy Inference System) methods in working groups building for R&D projects on the basis of employees skills.

Tritrichomonas foetus is described as a pathogen of cattle and cats and also exhibits commensalism with pigs. In order to estimate the prevalence and determine the risk factors for parasite infection, specimens from animal hosts (cat, pigs, and cattle) from Poland were investigated. To our best knowledge, this is the first such study to examine samples from wild boars (Sus scrofa) for the presence of T. foetus. Data were collected from 117 cats, 172 pigs, 236 wild boars, and 180 cattle. The sensitivity of T. foetus identification was increased by using two molecular assays: PCR and loop-mediated isothermal amplification (LAMP). The prevalence of feline tritrichomonosis was 20.51%, and statistically significant differences were obtained between groups of animals regarding age, breed, number of cats, diarrhea, and place of living. Positive PCR and LAMP results for T. foetus were estimated for 16.28% of pigs, and the obtained data were significantly correlated with age. Conversely, no significant differences were observed concerning the farm size factor. In our survey, no cases of bovine tritrichomonosis were found, which is consistent with the data from the other countries of the European Union. Similarly, all wild boar samples were also T. foetus-negative according to LAMP and PCR.

Contains fulltext : 177862.pdf (Publisher’s version ) (Open Access) Allogeneic islet transplantation into the liver in combination with immune suppressive drug therapy is widely regarded as a potential cure for type 1 diabetes. However, the intrahepatic system is suboptimal as the concentration of drugs and nutrients there is higher compared to pancreas, which negatively affects islet function. Islet encapsulation within semipermeable membranes is a promising strategy that allows for the islet transplantation outside the suboptimal liver portal system and provides environment, where islets can perform their endocrine function. In this study, we develop a macroencapsulation device based on thin microwell membranes. The islets are seeded in separate microwells to avoid aggregation, whereas the membrane porosity is tailored to achieve sufficient transport of nutrients, glucose and insulin. The non-degradable, microwell membranes are composed of poly (ether sulfone)/polyvinylpyrrolidone and manufactured via phase separation micro molding. Our results show that the device prevents aggregation and preserves the islet's native morphology. Moreover, the encapsulated islets maintain their glucose responsiveness and function after 7 days of culture (stimulation index above 2 for high glucose stimulation), demonstrating the potential of this novel device for islet transplantation.

Extrahepatic transplantation of islets of Langerhans could aid in better survival of islets after transplantation. When islets are transfused into the liver 60-70% of them are lost immediately after transplantation. An important factor for a successful extrahepatic transplantation is a well-vascularized tissue surrounding the implant. There are many strategies known for enhancing vessel formation such as adding cells with endothelial potential, the combination with angiogenic factors and / or applying surface topography at the exposed surface of the device. Previously we developed porous, micropatterned membranes which can be applied as a lid for an islet encapsulation device and we showed that the surface topography induces human umbilical vein endothelial cell (HUVEC) alignment and interconnection. This was achieved without the addition of hydrogels, often used in angiogenesis assays. In this work, we went one step further towards clinical implementation of the device by combining this micropatterned lid with Mesenchymal Stem Cells (MSCs) to facilitate prevascularization in vivo. As for HUVECs, the micropatterned membranes induced MSC alignment and organization in vitro, an important contributor to vessel formation, whereas in vivo (subcutaneous rat model) they contributed to improved implant prevascularization. In fact, the combination of MSCs seeded on the micropatterned membrane induced the highest vessel formation score in 80% of the sections. [Figure not available: see fulltext.].

The selection of an effective team of employees is crucial to proper management of the company. The success of the project often depends on the competencies of employees who carry out those projects. Therefore, the selection of the workers, whose competences complement each other in terms of subject matter, in terms of personality, and also in practical terms, is very important. This article presents the proposal of applying the FAHP (fuzzy analytic hierarchy process) and TOPSIS (technique for order preference by similarity to an ideal solution) methods as a tool to facilitate the management of human resources in the metal production factories based on the skills of employees.

The research presented in this thesis is about the development of novel membrane based macroencapsulation devices for improved pancreatic islet survival and function. To improve pancreatic islets functionality by avoiding their aggregation within macroencapsulation devices, we developed a novel microwell membrane based encapsulation device, where the islets are seeded in separate microwells avoiding their fusion and clustering. The membrane porosity is tailored to achieve shielding of the islets from the host immune cells without compromising their secretory responses. The non-degradable, microwell membranes are composed of poly (ether sulfone)/polyvinylpyrrolidone (PES/PVP) and manufactured via phase separation micromolding. The encapsulated islets maintain their glucose responsiveness demonstrating the potential of this novel device for islet transplantation. Moreover, we fabricated porous, micropatterned PES/PVP membranes and investigated the effect of patterns on human umbilical vein endothelial cell (HUVEC) alignment and interconnection as a first step towards the development of a stable prevascularized layer in vitro. The micropatterned surface, applied as lid for the microwell macroencapsulation device, would support cell organization during the development of a prevascularized layer on the outside of the device. Providing encapsulated islets with close proximity to blood vessels is important for their survival and function. Additionally, in order to mimic the β-cell relation with endothelial cells in native islets, we created stable composite aggregates by co-culture of mouse insulinoma MIN6 cells with HUVECs on a non-adherent agarose microwell platform. These composite aggregates maintain their function after encapsulation within our microwell PES/PVP device and show better insulin release than encapsulated pure MIN6 aggregates, indicating that providing the β-cells with a connection to the endothelial cells within an encapsulation device can improve the encapsulated cells’ functionality. As alternative for the flat configuration, we developed new PES/PVP multibore hollow fiber membranes for islet macroencapsulation. The fiber consists of seven bores and has high mechanical stability offering good protection to the encapsulated islets. Human islets encapsulated within the fiber bores retain their glucose responsiveness. Our new multibore hollow fiber membranes have higher islet encapsulation capacity than single-bore fibers and allow for easier up-scaling, which are important factors for the development of a clinically applicable bioartificial pancreas.

In this work, we developed a mixed matrix membrane by incorporating 20–40 μm size iminodiacetic acid modified immobeads within porous Ethylene vinyl alcohol (EVAL) polymer matrix. The MMM were charged with copper ions for selective adsorption of bovine hemoglobin in presence of bovine serum albumin. EVAL membrane without immobead and immobead alone showed low non-specific adsorption towards bovine hemoglobin and bovine serum albumin. Use of buffers with pH ⩽6.8 i.e. pI of bovine hemoglobin resulted in high bovine hemoglobin adsorption. The developed mixed matrix membrane has a maximum static adsorption capacity of 219.5 mg bovine hemoglobin per g bead and the adsorption isotherm curve is of a Langmuir type. Under similar flow rates, the mixed matrix membrane showed significant low pressure drop compared to a packed bed column containing equal amount of beads. Maximum and faster (6 h) adsorption of bovine hemoglobin can be achieved through dynamic mode only using mixed matrix membrane and not by packed bed column and static mode of mixed matrix membrane. The mixed matrix membrane has three times selective adsorption of bovine hemoglobin than bovine serum albumin, from a binary mixture containing equivalent amounts of both proteins.

Antiferroelectric Liquid Crystals are the promising materials for applications. Binary mixture was prepared using compounds which do not exhibit antiferroelectric phase. Final mixture indicate wide antiferroelectric phase. Dielectric spectroscopy was performed to identify mesogenic phases. A very strong BIAS field influence on dielectric behavior was found. It is clearly shown that the strong DC field eliminates the anticlinic SmCA* phase in favour of synclinic SmC* one.

Phase transitions in pure compounds with cyanoacetyloxyalkoxy groups in terminal chain (2) and second compound comprising alkanoyloxyalkoxy groups (1) and their bicomponent mixture have been studied by optical microscopy, differential scanning calorimetry (DSC) and dielectric spectroscopy. The temperatures, enthalpies of phase transitions and Cp values as a function of temperature were determined for such system by DSC method (Differential Scanning Calorimetry). Dielectric spectroscopy confirmed the presence of induced antiferroelectric phase in mixtures. The Goldstone-mode and the soft-mode relaxation process were observed for SmC* phase and also the low frequency PL and high frequency PH modes, which are typical for antiferroelectric phase.

Two ferroelectric three‐ring chiral esters, one with a partially fluorinated alkyl chain and another with a cyano terminal group, were mixed with a structurally similar compound having an alkyl terminal chain. In their mixtures an antiferroelectric phase was induced. The phase behaviour, spontaneous polarisation, tilt angle, smectic layer spacing and helical pitch of both systems were determined. The mechanism of the induction of an antiferroelectric phase is different in both cases, with highly tilted phases in former system and less tilted phases in the latter.

The phenomenon of an induction of the chiral anticlinic phase is described. The ability for induction of the antiferroelectric phase of compounds with cyano and fluorinated groups in terminal positions is tested by the comparison of phase diagrams of their mixtures. The results of DSC, electrooptic and X-ray measurements for two systems are presented. The induction of the antiferroelectric phase is confirmed by extensive physical studies.

The phase diagrams of binary mixtures composed of two chiral three ring esters are presented. The antiferroelectric SmC* A phase was induced in bicomponent mixtures comprising esters—one with alkanoyloxyalkoxy terminal chain and another one with cyanoacetyloxyalkoxy group. Influence of the length of terminal alkanoyloxy unit in the chain on the induction of the antiferroelectric phase is presented. For longer chain homologues the induction of SmC* A is stronger.

The results of helical pitch measurements for the systems, in which induced antiferroelectric phase is observed, are presented. The bicomponent systems composed of the chiral three ring ester with partially fluorinated terminal alkyl chain 4-(1-methylheptyloxycarbonyl)phenyl 4′-(1H,1H,2H,2H-perfluorooctyloxy)biphenylate-4 and a member of homologous series of chiral three ring ester with protonated chain – 4-(1-methylheptyloxycarbonyl)biphenyl-4′-yl 4-(3-alkanoyloxyprop-1-oxy)benzoates were investigated. The influence of alkyl chain length and the concentration of the hydrogenous component on the induction and helical pitch are discussed. The increase of concentration of a component with the alkyl chain causes the increase of helical pitch in ferro and antiferroelectric phase. The increase of alkyl chain length causes the lengthening of helical pitch in ferroelectric phase and shortening of it in antiferroelectric phase.

The induced antiferroelectric phase in bicomponent mixtures of fluorinated compound C6F13C2H4OPhPhCOOPhCOOC*H(CH3)C6H13 and a member of homologous series of CnH2n+1COO(CH2)3OPhCOOPhPhCOOC*H(CH3)C6H13 (n = 1-7) are observed. In those systems also SmC* α phase was evidenced. The helical pitch was measured and it was found that helical pitch increases with the increase of concentration of fluorinated component in mixture. The pitch of SmC*A phase is longer than for SmC* phase. Additionally the pitch in induced SmC*A phase does not depend on temperature, while in single compounds with SmC*A phase strongly increases.

Novel chiral esters with partially fluorinated alkoxyalkoxy terminal chains are described. Their phase transition temperatures, enthalpies, and electrooptical properties are reported. A helical pitch in pure compounds and their mixtures based on selective reflection of light is also characterized.

The DSC, electrooptic and X-ray results for the system composed of two synclinic compounds CNCH2COO(CH2)6OphPhCOOPhCOOC*H(CH3)C6H13 and C5H11COO(CH2)3OPhCOOPhPhCOOC*H(CH3)C6H13 are presented. The antiferroelectric SmC*A phase induces in this system and it was confirmed by physical measurements. It was found out that the mechanism of SmC*A phase induction is different than in systems comprising compound with perfluoroalkyl chain.

Two structurally similar homologous series of chiral esters with partially fluorinated alkoxyalkoxy terminal chains are described. Their synthetic routes and mesomorphic properties, such as phase transitions temperatures and enthalpies, are characterized by polarizing optical microscope and differential scanning calorimetry.

This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been removed at the request of the Executive Publisher.This article has been removed because it was published without the permission of the author(s).

(1) Background: Due to the increasing distribution of Echinococcus multilocularis infections in final hosts, epidemiological investigations are important for recognizing the spreading pattern of this parasite and also to estimate risk infection for humans. (2) Methods: Investigations were conducted with two commercial kits dedicated for DNA extraction from feces: ZR Fecal DNA Mini Prep (Zymo Research, Freiburg, Germany) and QIAamp FAST DNA Stool Mini Kit (Qiagen, Hilden, Germany) (marked as Z and Q), together with two common PCR protocols (nested PCR and multiplex PCR). The goal was to compare their efficiency in detecting the genetic material of E. multilocularis in the samples of feces. Stool samples from red foxes were collected in a highly endemic area in Poland. Sedimentation and counting technique (SCT) was used as a reference method. (3) Results: From 48 samples, 35 were positive in SCT. Further investigations showed that 40.0% of samples (from those with SCT positive result) after Z-DNA extraction and 45.7% after Q-DNA extraction gave positive results in nested PCR. In multiplex PCR, positive results were obtained in 54.3% of samples after Z isolation and 48.6% of samples after Q. Additionally, one sample that resulted in being negative in SCT gave a positive result in PCR. The number of worms detected in the intestines had no influence on PCR results. (4) Conclusions: Both of the extraction methods showed similar efficiency in DNA isolation and dealing with inhibitors, however, they showed relatively low sensitivity. This was probably caused by degradation of genetic material in the field-collected samples.