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Marketa Bacakova,*,1 Julia Pajorova,*,1,2 Antonin Broz,1 Daniel Hadraba,1,3 Frantisek Lopot,3 Anna Zavadakova,4 Lucie Vistejnova,4 Milan Beno,5 Ivan Kostic,6 Vera Jencova,7 Lucie Bacakova11Department of Biomaterials and Tissue Engineering, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic; 22nd Faculty of Medicine, Charles University, Prague, Czech Republic; 3Department of Anatomy and Biomechanics, Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic; 4Biomedical Center, Medical Faculty in Pilsen, Charles University, Pilsen, Czech Republic; 5Institute of Experimental Endocrinology, Biomedical Research Center of the Slovak Academy of Sciences, Bratislava, Slovak Republic; 6Institute of Informatics, Slovak Academy of Sciences, Bratislava, Slovak Republic; 7Department of Chemistry, Technical University of Liberec, Liberec, Czech Republic*These authors contributed equally to this workBackground: Repairs to deep skin wounds continue to be a difficult issue in clinical practice. A promising approach is to fabricate full-thickness skin substitutes with functions closely similar to those of the natural tissue. For many years, a three-dimensional (3D) collagen hydrogel has been considered to provide a physiological 3D environment for co-cultivation of skin fibroblasts and keratinocytes. This collagen hydrogel is frequently used for fabricating tissue-engineered skin analogues with fibroblasts embedded inside the hydrogel and keratinocytes cultivated on its surface. Despite its unique biological properties, the collagen hydrogel has insufficient stiffness, with a tendency to collapse under the traction forces generated by the embedded cells.Methods: The aim of our study was to develop a two-layer skin construct consisting of a collagen hydrogel reinforced by a nanofibrous poly-L-lactide (PLLA) membrane pre-seeded with fibroblasts. The attractiveness of the membrane for dermal fibroblasts was enhanced by coating it with a thin nanofibrous fibrin mesh.Results: The fibrin mesh promoted the adhesion, proliferation and migration of the fibroblasts upwards into the collagen hydrogel. Moreover, the fibroblasts spontaneously migrating into the collagen hydrogel showed a lower tendency to contract and shrink the hydrogel by their traction forces. The surface of the collagen was seeded with human dermal keratinocytes. The keratinocytes were able to form a basal layer of highly mitotically-active cells, and a suprabasal layer.Conclusion: The two-layer skin construct based on collagen hydrogel with spontaneously immigrated fibroblasts and reinforced by a fibrin-coated nanofibrous membrane seems to be promising for the construction of full-thickness skin substitute.Keywords: full-thickness skin substitutes, collagen hydrogel, fibroblast and keratinocyte co-cultivation, fibrin, nanostructure

Julia Pajorova,1 Marketa Bacakova,1 Jana Musilkova,1 Antonin Broz,1 Daniel Hadraba,1,2 Frantisek Lopot,2 Lucie Bacakova1 1Department of Biomaterials and Tissue Engineering, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic; 2Department of Anatomy and Biomechanics, Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic Background: Our study focuses on the fabrication of appropriate scaffolds for skin wound healing. This research brings valuable insights into the molecular mechanisms of adhesion, proliferation, and control of cell behavior through the extracellular matrix represented by synthetic biodegradable nanofibrous membranes coated by biomolecules. Methods: Nanofibrous polylactic acid (PLA) membranes were prepared by a needle-less electrospinning technology. These membranes were coated with fibrin according to two preparation protocols, and additionally they were coated with fibronectin in order to increase the cell affinity for colonizing the PLA membranes. The adhesion, growth, and extracellular matrix protein production of neonatal human dermal fibroblasts were evaluated on the nanofibrous membranes. Results: Our results showed that fibrin-coated membranes improved the adhesion and proliferation of human dermal fibroblasts. The morphology of the fibrin nanocoating seems to be crucial for the adhesion of fibroblasts, and consequently for their phenotypic maturation. Fibrin either covered the individual fibers in the membrane (F1 nanocoating), or covered the individual fibers and also formed a fine homogeneous nanofibrous mesh on the surface of the membrane (F2 nanocoating), depending on the mode of fibrin preparation. The fibroblasts on the membranes with the F1 nanocoating remained in their typical spindle-like shape. However, the cells on the F2 nanocoating were spread mostly in a polygon-like shape, and their proliferation was significantly higher. Fibronectin formed an additional mesh attached to the surface of the fibrin mesh, and further enhanced the cell adhesion and growth. The relative gene expression and protein production of collagen I and fibronectin were higher on the F2 nanocoating than on the F1 nanocoating. Conclusion: A PLA membrane coated with a homogeneous fibrin mesh seems to be promising for the construction of temporary full-thickness skin tissue substitutes. Keywords: nanofibers, fibrin, nanocoating, dermal fibroblasts, extracellular matrix synthesis, skin substitute, polylactic acid

Marketa Bacakova,1,2 Julia Pajorova,1,2 Denisa Stranska,3 Daniel Hadraba,1,4 Frantisek Lopot,4 Tomas Riedel,5 Eduard Brynda,5 Margit Zaloudkova,6 Lucie Bacakova1 1Department of Biomaterials and Tissue Engineering, Institute of Physiology, Czech Academy of Sciences, 2Second Faculty of Medicine, Charles University, Prague, 3InStar Technologies, Liberec, 4Department of Anatomy and Biomechanics, Faculty of Physical Education and Sport, Charles University, 5Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, 6Department of Composites and Carbon Materials, Institute of Rock Structure and Mechanics, Czech Academy of Sciences, Prague, Czech Republic Abstract: Protein-coated resorbable synthetic polymeric nanofibrous membranes are promising for the fabrication of advanced skin substitutes. We fabricated electrospun polylactic acid and poly(lactide-co-glycolic acid) nanofibrous membranes and coated them with fibrin or collagen I. Fibronectin was attached to a fibrin or collagen nanocoating, in order further to enhance the cell adhesion and spreading. Fibrin regularly formed a coating around individual nanofibers in the membranes, and also formed a thin noncontinuous nanofibrous mesh on top of the membranes. Collagen also coated most of the fibers of the membrane and randomly created a soft gel on the membrane surface. Fibronectin predominantly adsorbed onto a thin fibrin mesh or a collagen gel, and formed a thin nanofibrous structure. Fibrin nanocoating greatly improved the attachment, spreading, and proliferation of human dermal fibroblasts, whereas collagen nanocoating had a positive influence on the behavior of human HaCaT keratinocytes. In addition, fibrin stimulated the fibroblasts to synthesize fibronectin and to deposit it as an extracellular matrix. Fibrin coating also showed a tendency to improve the ultimate tensile strength of the nanofibrous membranes. Fibronectin attached to fibrin or to a collagen coating further enhanced the adhesion, spreading, and proliferation of both cell types. Keywords: skin-tissue engineering, nanocoating, nanofibers, skin cells, fibrin, collagen

There are two distinct facets of adequate fluid balance control in haemodialysis patients--estimation of dry weight (DW) as the target and adequate ultrafiltration (UF) strategy, i.e. the way to reach the target in a possibly symptom-free way. The article reviews the continuous blood volume monitoring (CBVM) based procedures to deal with the former facet-DW determination. The existing approaches are divided in three groups--methods defining certain alert value of relative blood volume (RBV) reduction, methods working with RBV response to constant UF rate, and methods evaluating dynamics of RBV response to UF pulse or chain of UF pulses. While the first and the third approaches are relatively easy to automate, the second group of methods are suitable mainly for observational evaluations only. All the discussed methods, without exception, need large-scale verification, as they all were evaluated in the majority by their authors only and on small patient cohorts. [ABSTRACT FROM AUTHOR]

This article reviews vascular access (VA) assessment methods and procedures. It gives an overview of the existing methods for bed-side VA assessment by means of pressures, recirculation and access flow measurement. Pros and cons of the methods are discussed and additional benefits of a combined recirculation and access flow measurement are explained. Present vascular access care guidelines are discussed, namely the K/DOQI and EVAS documents. Practical setup of a vascular access monitoring and surveillance system is illustrated with data from the authors' own unit where such a system has been in use since 1999. The issue of adequate target setting is analysed in view of published works on clinical impact of access surveillance system introduction (timely detection of access stenosis and access patency). Critical re-evaluation is needed especially in current QVA threshold and intervention timing. [ABSTRACT FROM AUTHOR]

Presents the discussion paper for hemodynamics and electrolyte balance. Synopsis of the discussion paper; Themes of the discussion; Effects of thermal energy transfer during treatment.

Dynamic arterial and venous pressures (PA, PV) are used as the simplest tools to assess vascular access quality (VAQ). An increased PV over three consecutive dialyses is believed to indicate a stenosis, a rule devised for synthetic grafts (AVG) but not adequately validated for AV fistulas (AVF). In this study dynamic PV and static intra-access pressure (calculated by means of the simplified formula PIA=(PA+PV)/2) changes were evaluated in 46 accesses in which balloon angioplasty had to eventually be performed. The whole group consisted of 30 forearm AVF, 5 upper arm AVF and 11 AVG. Pressures were compared in each patient at a time of satisfactory access flow (QVA) and immediately before the angioplasty and pressure difference over that period (deltaPV, deltaPIA) evaluated. Despite a significant drop in QVA over the follow-up interval in both AVF and AVG, the mean deltaPV and deltaPIA in AVF were only several mm Hg and the chosen threshold limit of 20 mmHg was exceeded in approximately 10% of patients only. The results in the AVG group were, however, very different: The mean deltaPV and deltaPIA were close to 20 mmHg and almost 60% of patients in the AVG group exceeded this limit. Evaluation of PIA did not improve stenosis detection in either group. It is concluded that PV and/or PIA monitoring may be useful to detect a stenosis in AVG but not in AVF. [ABSTRACT FROM AUTHOR]

As was shown in the previous part of the study, windshields are an important part of the passive safety means of modern low-floor trams with an extraordinary effect on pedestrian safety in a pedestrian-tram collisions. Therefore, maximum attention must be paid to the definition of tram windshield characteristics. This article describes a windshield crash test, from which data are obtained to verify the feasibility of the applied computational approaches. A developed analytical model is utilised for a simple description of the energy balance during collision with an illustrative definition of the important parameters of laminated glass as well as their clear physical interpretations. The finite element analysis (FEA) performed in Ansys software using two versions of material definition, namely a simpler (*MAT_ELASTIC with nonlocal failure criterion) and a more complex (*MAT_GLASS with brittle stress-state-dependent failure) material model, which are presented as suitable for obtaining a detailed description of the shattering process of laminated glass, which can also be used effectively in windshield engineering.

This article represents the first paper in a two-part series dealing with safety during tram-pedestrian collisions. This research is dedicated to the safety of trams for pedestrians during collisions and is motivated by the increased number of lethal cases. The first part of this paper includes an overview of tram face development from the earliest designs to the current ones in use and, at the same time, provides a synopsis and explanation of the technical context, including a link to current and forthcoming legislation. The historical design development can be characterised by three steps, from an almost vertical front face, to leaned and pointed shapes, to the current inclined low-edged windshield without a protruding coupler. However, since most major manufacturers now export their products worldwide and customisation is only of a technically insignificant nature, our conclusions are generalisable (supported by the example of Berlin). The most advantageous shape of the tram's front, minimising the effects on pedestrians in all collision phases, has evolved rather spontaneously and was unprompted, and it is now being built into the European Commission regulations. The goal of the second part of this paper is to conduct a series of tram-pedestrian collisions with a focus on the frontal and side impacts using a crash test dummy (anthropomorphic test device-ATD). Four tram types approaching the collision at four different impact speeds (5 km/h, 10 km/h, 15 km/h, and 20 km/h) were used. The primary outcome variable was the resultant head acceleration. The risk and severity of possible head injuries were assessed using the head injury criterion ( HIC 15 ) and its linkage to the injury level on the Abbreviated Injury Scale (AIS). The results showed increasing head impacts with an increasing speed for all tram types and collision scenarios. Higher values of head acceleration were reached during the frontal impact (17-124 g) compared to the side one (2-84 g). The HIC 15 values did not exceed the value of 300 for any experimental setting, and the probability of AIS4+ injuries did not exceed 10%. The outcomes of tram-pedestrian collisions can be influenced by the ATD's position and orientation, the impact speed and front-end design of trams, and the site of initial contact.

Purpose: Low back pain is a significant socio-economic problem which is expected to deepen. Degenerative disc disease is considered to be one of its main causes. Unsuccessful conservative treatments usually lead to surgical treatments, including methods providing pain relief by vertebral fusion in the affected segment. However, this leads to changes in biomechanics, which is why approximately 30 years ago total disc replacements appeared. This work aims at determining the current state of treatments with this kind of replacement, comparing the results with those of fusion methods and assessing why fusion continues to dominate. Current treatments of degenerative disc disease by advanced procedures (regenerative and gene therapy, 3D printing) is also examined and evaluated, and future developments are considered., Methods: A critical review based on available scientific articles from online databases. The main keywords used were "lumbar", "total", "disc" and "replacement", supplemented according to the individual, monitored areas ("follow-up", "fusion", "future" etc.). For the articles found through database search (n = 895), narrower selection was made and the result was 33 articles included in review., Review: Total disc replacements have not yet satisfactorily demonstrated that they are superior to fusion methods in long term follow-up. Advanced methods are in their infancy., Conclusions: Additional research and development of total disc replacements is still necessary. For implants, the 3D scan - 3D model - 3D printing chain and its related technologies are increasingly important. The development of regenerative procedures using induced pluripotent stem cells and gene therapies is important, but conservative treatments and primary prevention should also be developed because regenerative procedures and gene therapies apparently will not be used routinely until the future.

Clubfoot is one of the most common musculoskeletal birth deformities worldwide. The prevalence varies among individual countries and populations. There is a lack of nationwide incidence studies in Central Europe. We analyzed the incidence of clubfoot in the Czech Republic over 14 years. Patients born with clubfoot in the Czech Republic were identified using The National Registry of Congenital Anomalies. Demographic data were included. Data from 2000 to 2014 were collected and analyzed regarding gender and regional distribution. The study's chosen time frame was grounded on the condition of the Czech industry. Following extensive transformations in 1989, the industry eliminated highly non-ecological operations with significant environmental impact and related health risks. The incidence of clubfoot during the study period was 1.9 (95% CI 1.8-2.0) per 1000 births; males comprised the majority (59%). The incidence significantly differed among individual regions of the Czech Republic ( p < 0.001). The incidence in the Czech Republic was higher than in previous European studies. We found significant regional differences in incidence, which could indicate that there may be exogenous pathogenic factors. For this reason, we plan to follow up our work with an up-to-date study.

Background: Data on renal replacement therapy (RRT) for end-stage renal disease were collected by the European Renal Association (ERA) Registry via national and regional renal registries in Europe and countries bordering the Mediterranean Sea. This article provides a summary of the 2019 ERA Registry Annual Report, including data from 34 countries and additional age comparisons., Methods: Individual patient data for 2019 were provided by 35 registries and aggregated data by 17 registries. Using these data, the incidence and prevalence of RRT, the kidney transplantation activity and the survival probabilities were calculated., Results: In 2019, a general population of 680.8 million people was covered by the ERA Registry. Overall, the incidence of RRT was 132 per million population (p.m.p.). Of these patients, 62% were men, 54% were ≥65 years of age and 21% had diabetes mellitus as primary renal disease (PRD), and 84% had haemodialysis (HD), 11% had peritoneal dialysis (PD) and 5% had pre-emptive kidney transplantation as an initial treatment modality. The overall prevalence of RRT on 31 December 2019 was 893 p.m.p., with 58% of patients on HD, 5% on PD and 37% living with a kidney transplant. The overall kidney transplant rate was 35 p.m.p. and 29% of the kidney grafts were from a living donor. The unadjusted 5-year survival probability was 42.3% for patients commencing dialysis, 86.6% for recipients of deceased donor grafts and 94.4% for recipients of living donor grafts in the period 2010-14. When comparing age categories, there were substantial differences in the distribution of PRD, treatment modality and kidney donor type, and in the survival probabilities., (© The Author(s) 2021. Published by Oxford University Press on behalf of the ERA.)

Methods: Records of 10,000 QVA measurement performed in 549 patients over 20 years were used as retrospective and anonymized data source, making ethical commission involvement unnecessary. Two approaches are used to elucidate association of QVA changes with different factors: analyses of smaller cohorts in which both the QVA and the respective factor were measured (e.g. association of QVA with cardiac output (CO)), or-in case of rare phenomena-a form of a well illustrated case reports was used (e.g. association of QVA and Kt/V)., Results: Significant increase in CO after permanent VA creation (3-4-fold of the QVA value) was found. Impact of intradialytic CO changes on QVA is attenuated by relatively stable VA resistance compared to systemic resistance. Blood pressure impact is much stronger and it should therefore be noted at each QVA measurement. As reproducibility of different QVA measurement methods varies, use of the same method should be preferred. Direction of the arterial needle insertion in VA affects the QVA measured, especially in synthetic grafts, too. Also patient's own QVA variability may be quite high. All this makes KDOQI/EBPG recommended acceptable QVA drops too strict, they should be revised. In re-stenoses prone patients, measurement intervals should be shortened, too., Conclusion: QVA values are significantly affected by many factors. Their knowledge appears essential for safe and effective VA surveillance and management.

The article deals with the measurement of dynamic effects that are transmitted to the driver (passenger) when driving in a car over obstacles. The measurements were performed in a real environment on a defined track at different driving speeds and different distributions of obstacles on the road. The reaction of the human organism, respectively the load of the cervical vertebrae and the heads of the driver and passenger, was measured. Experimental measurements were performed for different variants of driving conditions on a 28-year-old and healthy man. The measurement's main objective was to determine the acceleration values of the seats in the vehicle in the vertical movement of parts of the vehicle cabin and to determine the dynamic effects that are transmitted to the driver and passenger in a car when driving over obstacles. The measurements were performed in a real environment on a defined track at various driving speeds and diverse distributions of obstacles on the road. The acceleration values on the vehicle's axles and the structure of the driver's and front passenger's seats, under the buttocks, at the top of the head (Vertex Parietal Bone) and the C7 cervical vertebra (Vertebra Cervicales), were measured. The result of the experiment was to determine the maximum magnitudes of acceleration in the vertical direction on the body of the driver and the passenger of the vehicle when passing a passenger vehicle over obstacles. The analysis of the experiment's results is the basis for determining the future direction of the research.

Background: The European Renal Association - European Dialysis and Transplant Association (ERA-EDTA) Registry collects data on kidney replacement therapy (KRT) via national and regional renal registries in Europe and countries bordering the Mediterranean Sea. This article summarizes the 2018 ERA-EDTA Registry Annual Report, and describes the epidemiology of KRT for kidney failure in 34 countries., Methods: Individual patient data on patients undergoing KRT in 2018 were provided by 34 national or regional renal registries and aggregated data by 17 registries. The incidence and prevalence of KRT, the kidney transplantation activity and the survival probabilities of these patients were calculated., Results: In 2018, the ERA-EDTA Registry covered a general population of 636 million people. Overall, the incidence of KRT for kidney failure was 129 per million population (p.m.p.), 62% of patients were men, 51% were ≥65 years of age and 20% had diabetes mellitus as cause of kidney failure. Treatment modality at the onset of KRT was haemodialysis (HD) for 84%, peritoneal dialysis (PD) for 11% and pre-emptive kidney transplantation for 5% of patients. On 31 December 2018, the prevalence of KRT was 897 p.m.p., with 57% of patients on HD, 5% on PD and 38% living with a kidney transplant. The transplant rate in 2018 was 35 p.m.p.: 68% received a kidney from a deceased donor, 30% from a living donor and for 2% the donor source was unknown. For patients commencing dialysis during 2009-13, the unadjusted 5-year survival probability was 42.6%. For patients receiving a kidney transplant within this period, the unadjusted 5-year survival probability was 86.6% for recipients of deceased donor grafts and 93.9% for recipients of living donor grafts., (© The Author(s) 2020. Published by Oxford University Press on behalf of ERA-EDTA.)

Decellularized human pericardium is under study as an allogenic material for cardiovascular applications. The effects of crosslinking on the mechanical properties of decellularized pericardium were determined with a uniaxial tensile test, and the effects of crosslinking on the collagen structure of decellularized pericardium were determined by multiphoton microscopy. The viability of human umbilical vein endothelial cells seeded on decellularized human pericardium and on pericardium strongly and weakly crosslinked with glutaraldehyde and with genipin was evaluated by means of an MTS assay. The viability of the cells, measured by their metabolic activity, decreased considerably when the pericardium was crosslinked with glutaraldehyde. Conversely, the cell viability increased when the pericardium was crosslinked with genipin. Coating both non-modified pericardium and crosslinked pericardium with a fibrin mesh or with a mesh containing attached heparin and/or fibronectin led to a significant increase in cell viability. The highest degree of viability was attained for samples that were weakly crosslinked with genipin and modified by means of a fibrin and fibronectin coating. The results indicate a method by which in vivo endothelialization of human cardiac allografts or xenografts could potentially be encouraged.

Aim: This study evaluates the effect of electrospun dressings in critical sized full-thickness skin defects in rabbits. Materials & methods: Electrospun poly-ε-caprolactone (PCL) and polyvinyl alcohol (PVA) nanofibers were tested in vitro and in vivo . Results: The PCL scaffold supported the proliferation of mesenchymal stem cells, fibroblasts and keratinocytes. The PVA scaffold showed significant swelling, high elongation capacity, limited protein adsorption and stimulation of cells. Nanofibrous dressings improved wound healing compared with the control group in vivo . A change of the PCL dressing every 7 days resulted in a decreased epithelial thickness and type I collagen level in the adhesive group, indicating peeling off of the newly formed tissue. In the PVA dressings, the exchange did not affect healing. Conclusion: The results demonstrate the importance of proper dressing exchange.

Background: This article summarizes the ERA-EDTA Registry's 2016 Annual Report, by describing the epidemiology of renal replacement therapy (RRT) for end-stage renal disease (ESRD) in 2016 within 36 countries., Methods: In 2017 and 2018, the ERA-EDTA Registry received data on patients undergoing RRT for ESRD in 2016 from 52 national or regional renal registries. In all, 32 registries provided individual patient data and 20 provided aggregated data. The incidence and prevalence of RRT and the survival probabilities of these patients were determined., Results: In 2016, the incidence of RRT for ESRD was 121 per million population (pmp), ranging from 29 pmp in Ukraine to 251 pmp in Greece. Almost two-thirds of patients were men, over half were aged ≥65 years and almost a quarter had diabetes mellitus as their primary renal diagnosis. Treatment modality at the start of RRT was haemodialysis for 84% of patients. On 31 December 2016, the prevalence of RRT was 823 pmp, ranging from 188 pmp in Ukraine to 1906 pmp in Portugal. In 2016, the transplant rate was 32 pmp, varying from 3 pmp in Ukraine to 94 pmp in the Spanish region of Catalonia. For patients commencing RRT during 2007-11, the 5-year unadjusted patient survival probability on all RRT modalities combined was 50.5%. For 2016, the incidence and prevalence of RRT were higher among men (187  and 1381 pmp) than women (101 and 827 pmp), and men had a higher rate of kidney transplantation (59 pmp) compared with women (33 pmp). For patients starting dialysis and for patients receiving a kidney transplant during 2007-11, the adjusted patient survival probabilities appeared to be higher for women than for men., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA.)

Dialysate conductivity is routinely used as a surrogate for dialysate sodium concentration. However, dialysis machine manufacturers apply different conductivity temperature correction coefficients. With the same conductivity in dialysis machines manufactured by different manufacturers, dialysate sodium may significantly differ. Also, electrolyte prescriptions are individualized (K, Ca, HCO3) and this is associated with another variation in dialysate sodium in the order of 1-5 mmol/L and both deviations are cumulative and chronic for each patient. Equivalence of the prescribed dialysate sodium and the concentration measured in it is not granted. Both variables differ and it is machine dependent! This paper analyses those variations from a technical point of view and suggests how to detect them and how to deal with or avoid them in clinical practice., (© 2018 S. Karger AG, Basel.)

Fibrillar collagen in tendons and its natural development in rabbits are discussed in this paper. Achilles tendons from newborn (~7 days) to elderly (~38 months) rabbits were monitored in intact (n tendons=24) and microtome sectioned (n tendons=11) states with label-free second harmonic generation microscopy. After sectioning, the collagen fiber pattern was irregular for the younger animals and remained oriented parallel to the load axis of the tendon for the older animals. In contrast, the collagen fiber pattern in the intact samples followed the load axis for all the age groups. However, there was a significant difference in the tendon crimp pattern appearance between the age groups. The crimp amplitude (A) and wavelength (Λ) started at very low values (A=2.0±0.6 µm, Λ=19±4 µm) for the newborn animals. Both parameters increased for the sexually mature animals (>5 months old). When the animals were fully mature the amplitude decreased but the wavelength kept increasing. The results revealed that the microtome sectioning artifacts depend on the age of animals and that the collagen crimp pattern reflects the physical growth and development.

Background: This article summarizes the European Renal Association - European Dialysis and Transplant Association Registry's 2014 annual report. It describes the epidemiology of renal replacement therapy (RRT) for end-stage renal disease (ESRD) in 2014 within 35 countries. Methods: In 2016, the ERA-EDTA Registry received data on patients who in 2014 where undergoing RRT for ESRD, from 51 national or regional renal registries. Thirty-two registries provided individual patient level data and 19 provided aggregated patient level data. The incidence, prevalence and survival probabilities of these patients were determined. Results: In 2014, 70 953 individuals commenced RRT for ESRD, equating to an overall unadjusted incidence rate of 133 per million population (pmp). The incidence ranged by 10-fold; from 23 pmp in the Ukraine to 237 pmp in Portugal. Of the patients commencing RRT, almost two-thirds were men, over half were aged ≥65 years and a quarter had diabetes mellitus as their primary renal diagnosis. By day 91 of commencing RRT, 81% of patients were receiving haemodialysis. On 31 December 2014, 490 743 individuals were receiving RRT for ESRD, equating to an unadjusted prevalence of 924 pmp. This ranged throughout Europe by more than 10-fold, from 157 pmp in the Ukraine to 1794 pmp in Portugal. In 2014, 19 406 kidney transplantations were performed, equating to an overall unadjusted transplant rate of 36 pmp. Again this varied considerably throughout Europe. For patients commencing RRT during 2005-09, the 5-year-adjusted patient survival probabilities on all RRT modalities was 63.3% (95% confidence interval 63.0-63.6). The expected remaining lifetime of a 20- to 24-year-old patient with ESRD receiving dialysis or living with a kidney transplant was 21.9 and 44.0 years, respectively. This was substantially lower than the 61.8 years of expected remaining lifetime of a 20-year-old patient without ESRD.

Objective: The human motion system reacts to both hypo and hyperactivity loads by changes to the rheological properties of tissues. This study deals with changes to the axial system (AS) compartment. Using the appropriate methodologies and mathematical-physical methods, these changes can be identified and quantified., Methods: This study describes the noninvasive TVS (Transfer Vibration through Spine) method, which was applied to assess the AS selected mechanical properties in various modes. A pilot study was conducted on a top-level twelve-year-old girl-gymnast. The data detection was carried out in three cycles, before and after a peak 3.5 hour training session and the next day, after resting, just before the next training., Results: Specifically, the values of selected rheological parameters, the AS damping coefficient b and viscosity μ, were obtained. The dynamics of their changes, in the stated load cycles, has also been shown. The damping coefficient b fell from the value of 0.626 to 0.324 before training and increased to 0.394 after resting. The viscosity coefficient μ showed a similar trend, namely falling from the value of 9.85 [Pa.s] to 2.15 [Pa.s] and then increasing to 3.8 [Pa.s] ., Conclusions: With its computational solution, the TVS method,is a diagnostic apparatus making it possible to classify AS properties, both quantitatively and qualitatively, or its chosen segments and their changes, respectively. It can be used in classifying, preventing and treating the consequences of extreme motion and relaxing modes. The TVS application also makes it possible to control AS states over therapeutic, recovery, ergonomic and other loading modes of the human locomotion system.

Background: This article provides a summary of the 2013 European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry Annual Report (available at http://www.era-edta-reg.org), with a focus on patients with diabetes mellitus (DM) as the cause of end-stage renal disease (ESRD)., Methods: In 2015, the ERA-EDTA Registry received data on renal replacement therapy (RRT) for ESRD from 49 national or regional renal registries in 34 countries in Europe and bordering the Mediterranean Sea. Individual patient data were provided by 31 registries, while 18 registries provided aggregated data. The total population covered by the participating registries comprised 650 million people., Results: In total, 72 933 patients started RRT for ESRD within the countries and regions reporting to the ERA-EDTA Registry, resulting in an overall incidence of 112 per million population (pmp). The overall prevalence on 31 December 2013 was 738 pmp (n = 478 990). Patients with DM as the cause of ESRD comprised 24% of the incident RRT patients (26 pmp) and 17% of the prevalent RRT patients (122 pmp). When compared with the USA, the incidence of patients starting RRT pmp secondary to DM in Europe was five times lower and the incidence of RRT due to other causes of ESRD was two times lower. Overall, 19 426 kidney transplants were performed (30 pmp). The 5-year adjusted survival for all RRT patients was 60.9% [95% confidence interval (CI) 60.5-61.3] and 50.6% (95% CI 49.9-51.2) for patients with DM as the cause of ESRD.

Phosphorus removal by hemoelimination procedure is a important mechanism to maintain phosphorus level in acceptable level in patients on dialysis. Phosphorus is removed by both diffusion and convection, but in clinical practice, it is not possible to differentiate the contribution of this two transport modalities. We used Gutzwiller formula to quantify the amount of removed phosphorus and compared it in low-flux hemodialysis (LFHD), high-flux hemodialysis (HFHD), and on-line hemodiafiltration (HDF). There were no significant differences in phosphorus predialysis concentration, duration of procedure, processed blood volume and ultrafiltration, e.g., factors, which could possibly influence phosphorus elimination. All three tested dialysis modes also did not differ in urea dialysis dose (Kt/V) as a parameter of small molecular weight removal (LFHD, 1.50 ± 0.04 vs HFHD, 1.5 ± 0.06 vs HDF, 1.5 ± 0.05). The amount of removed phosphorus in LFHD, HFHD, and HDF was 34.0 ± 1.2, 37.8 ± 1.6, and 38.3 ± 1.4 mmol, respectively. Statistically significant increase in phosphorus removal was seen only with use of high-flux membrane (HFHD and HDF) when compared with the low-flux one. No difference was, however, found between HFHD and HDF. It can thus be concluded that phosphorus removal in all three dialysis modes is a predominantly diffusive issue and contribution of convection to it is minor to negligible.

Background: This article summarizes the 2012 European Renal Association-European Dialysis and Transplant Association Registry Annual Report (available at www.era-edta-reg.org) with a specific focus on older patients (defined as ≥65 years)., Methods: Data provided by 45 national or regional renal registries in 30 countries in Europe and bordering the Mediterranean Sea were used. Individual patient level data were received from 31 renal registries, whereas 14 renal registries contributed data in an aggregated form. The incidence, prevalence and survival probabilities of patients with end-stage renal disease (ESRD) receiving renal replacement therapy (RRT) and renal transplantation rates for 2012 are presented., Results: In 2012, the overall unadjusted incidence rate of patients with ESRD receiving RRT was 109.6 per million population (pmp) (n = 69 035), ranging from 219.9 pmp in Portugal to 24.2 pmp in Montenegro. The proportion of incident patients ≥75 years varied from 15 to 44% between countries. The overall unadjusted prevalence on 31 December 2012 was 716.7 pmp (n = 451 270), ranging from 1670.2 pmp in Portugal to 146.7 pmp in the Ukraine. The proportion of prevalent patients ≥75 years varied from 11 to 32% between countries. The overall renal transplantation rate in 2012 was 28.3 pmp (n = 15 673), with the highest rate seen in the Spanish region of Catalonia. The proportion of patients ≥65 years receiving a transplant ranged from 0 to 35%. Five-year adjusted survival for all RRT patients was 59.7% (95% confidence interval, CI: 59.3-60.0) which fell to 39.3% (95% CI: 38.7-39.9) in patients 65-74 years and 21.3% (95% CI: 20.8-21.9) in patients ≥75 years.

It may be possible to regulate the cell colonization of biodegradable polymer nanofibrous membranes by plasma treatment and by the density of the fibers. To test this hypothesis, nanofibrous membranes of different fiber densities were treated by oxygen plasma with a range of plasma power and exposure times. Scanning electron microscopy and mechanical tests showed significant modification of nanofibers after plasma treatment. The intensity of the fiber modification increased with plasma power and exposure time. The exposure time seemed to have a stronger effect on modifying the fiber. The mechanical behavior of the membranes was influenced by the plasma treatment, the fiber density, and their dry or wet state. Plasma treatment increased the membrane stiffness; however, the membranes became more brittle. Wet membranes displayed significantly lower stiffness than dry membranes. X-ray photoelectron spectroscopy (XPS) analysis showed a slight increase in oxygen-containing groups on the membrane surface after plasma treatment. Plasma treatment enhanced the adhesion and growth of HaCaT keratinocytes on nanofibrous membranes. The cells adhered and grew preferentially on membranes of lower fiber densities, probably due to the larger area of void spaces between the fibers., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Central venous catheter (CVC)-related problems, risks and safety hazards are partly caused by different characteristics of the CVC-based access and their performance features. This chapter covers those issues in a chronological order, from factors related to the choice of the CVC, insertion site and insertion procedure itself, over those associated with CVC use and their monitoring up to safety hazards of interventional procedures. Not discussed are CVC infections as they are covered in a separate chapter in this book., (© 2015 S. Karger AG, Basel.)

Various types of nanofibers are increasingly used in tissue engineering, mainly for their ability to mimic the architecture of tissue at the nanoscale. We evaluated the adhesion, growth, viability, and differentiation of human osteoblast-like MG 63 cells on polylactide (PLA) nanofibers prepared by needle-less electrospinning and loaded with 5 or 15 wt % of hydroxyapatite (HA) nanoparticles. On day 7 after seeding, the cell number was the highest on samples with 15 wt % of HA. This result was confirmed by the XTT test, especially after dynamic cultivation, when the number of metabolically active cells on these samples was even higher than on control polystyrene. Staining with a live/dead kit showed that the viability of cells on all nanofibrous scaffolds was very high and comparable to that on control polystyrene dishes. An enzyme-linked immunosorbent assay revealed that the concentration of osteocalcin was also higher in cells on samples with 15 wt % of HA. There was no immune activation of cells (measured by production of TNF-alpha), associated with the incorporation of HA. Moreover, the addition of HA suppressed the creep behavior of the scaffolds in their dry state. Thus, nanofibrous PLA scaffolds have potential for bone tissue engineering, particularly those with 15 wt % of HA., (© 2013 Wiley Periodicals, Inc.)

Background: This article provides a summary of the 2011 ERA-EDTA Registry Annual Report (available at www.era-edta-reg.org)., Methods: Data on renal replacement therapy (RRT) for end-stage renal disease (ESRD) from national and regional renal registries in 30 countries in Europe and bordering the Mediterranean Sea were used. From 27 registries, individual patient data were received, whereas 17 registries contributed data in aggregated form. We present the incidence and prevalence of RRT, and renal transplant rates in 2011. In addition, survival probabilities and expected remaining lifetimes were calculated for those registries providing individual patient data., Results: The overall unadjusted incidence rate of RRT in 2011 among all registries reporting to the ERA-EDTA Registry was 117 per million population (pmp) (n = 71.631). Incidence rates varied from 24 pmp in Ukraine to 238 pmp in Turkey. The overall unadjusted prevalence of RRT for ESRD on 31 December 2011 was 692 pmp (n = 425 824). The highest prevalence was reported by Portugal (1662 pmp) and the lowest by Ukraine (131 pmp). Among all registries, a total of 22 814 renal transplantations were performed (37 pmp). The highest overall transplant rate was reported from Spain, Cantabria (81 pmp), whereas the highest rate of living donor transplants was reported from Turkey (39 pmp). For patients who started RRT between 2002 and 2006, the unadjusted 5-year patient survival on RRT was 46.8% [95% confidence interval (CI) 46.6-47.0], and on dialysis 39.3% (95% CI 39.2-39.4). The unadjusted 5-year patient survival after the first renal transplantation performed between 2002 and 2006 was 86.7% (95% CI 86.2-87.2) for kidneys from deceased donors and 94.3% (95% CI 93.6-95.0) for kidneys from living donors.

Background: This study provides a summary of the 2010 European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry Annual Report (available at www.era-edta-reg.org)., Methods: This report includes data on renal replacement therapy (RRT) using data from the national and regional renal registries in 29 countries in Europe and bordering the Mediterranean Sea. Individual patient data were received from 27 registries, whereas 18 registries contributed data in aggregated form. We present incidence and prevalence of RRT, transplant rates, survival probabilities and expected remaining lifetimes. The latter two are solely based on individual patient records., Results: In 2010, the overall incidence rate of RRT for end-stage renal disease (ESRD) among all registries reporting to the ERA-EDTA Registry was 123 per million population (pmp) ( n = 91 798). The highest incidence rate was reported by Turkey (252pmp) and the lowest reported by Montenegro (21 pmp). The overall prevalence of RRT for ESRD at 31 December 2010 among all registries reporting to the ERA-EDTA Registry was 741 pmp ( n = 551 005). The prevalence varied from 124 pmp in Ukraine to 1580 pmp in Portugal. The overall number of renal transplantations performed in 2010 among all registries was 29.2 pmp ( n = 21 740). The highest overall transplant rate was reported from Spain, Cantabria (73 pmp), whereas the highest transplant rate for living donor kidneys was reported from the Netherlands (28 pmp). For patients who started RRT between 2001 and 2005, the unadjusted 5-year patient survival on RRT was 46.2% [95% confidence interval (CI) 46.0-46.3], and on dialysis 38.6% (95% CI 38.5-38.8). The unadjusted 5-year patient survival after the first renal transplantation performed between 2001 and 2005 was 86.6% (95% CI 86.1-87.1) for deceased donor kidneys and 94.1% (95% CI 93.4-94.8) for living donor kidneys.

Objective: For the evaluation of neck injury the relative distance was observed between a marker placed on the forehead and a marker placed on the shoulder and also by change of the angle. To compare the severity of head injury a value of maximum head acceleration was used, HIC and a 3 ms criterion. All criteria were related to the activity of musculus sternocleidomastoideus and musculus trapezius in a situation of expected or unexpected impact., Materials and Methods: The situation was recorded using a Qualisys system, head acceleration of probands in three axes was recorded using the accelerometer, activity of neck muscles was monitored by a mobile EMG., Results: Maximum head acceleration was 12.1 g for non-visual and 8.2 g for visual. HIC36 was 5.7 non visual and 4.0 for visual. 3-ms criterion was 11.5 g for non-visual and 7.8 g for visual. The average time of muscle activation of the observed group without visual perception is 0.027 s after hitting an obstacle, with visual perception 0.127 s before the crash., Conclusions: Kinematic values indicate more favourable parameters for neck injuries for visual. Head injury criteria show an average decrease of about 30% for visual. We can conclude that the visual perception means a significant increase in pre-activation of the observed muscle group of almost 400% and lower activation in both following phases of approximately 40%.