Multidisciplinary surgical approach to renal cancer with vena cava invasion and pulmonary embolism.

INTRODUCTION: Renal cancer is unique for many reasons. One reason is that renal cell carcinoma can grow directly into the drainage veins of the kidney, which enter the inferior vena cava leading to the heart. This growth of tumor cells into the veins is called a tumor thrombus and is a locally aggressive renal cancer. The present article informs about the experience of our cardiac surgery department together with the transplant surgery department in successful surgical removal of a kidney with tumor, with invasion into the inferior vena cava, right atrium of the heart and pulmonary artery in two case reports. CASE REPORTS: A 32 years old female without significant history, with suddenly evolving dyspnea was urgently admitted to hospital. Her condition was suspected to be caused by pulmonary artery embolisation. The diagnosis was confirmed by CT scan which revealed unknown tumor mass of the right kidney and tumor embolisation in inferior vena cava and pulmonary artery. The patient was urgently operated by a vascular surgeon and cardiothoracic surgeon. They successfully performed left radical nephrectomy and total thromboembolectomy of the tumorous masses from vena cava inferior and pulmonary artery. The postoperative course was without complications, postoperative CT revealed no residual masses, and the patient was discharged in a good condition from the hospital. A 58 years old male with arterial hypertension suffered from orchiepididymitis. CT scan showed a tumor of the left kidney with propagation of tumorous masses to inferior vena cava and pulmonary artery. In elective surgery the vascular surgeon and cardiothoracic surgeon successfully performed left radical nephrectomy with total thromboembolectomy of the tumorous masses from inferior vena cava and pulmonary artery. After surgery a temporary paralytic ileus and an episode of atrial fibrillation occurred. Both are common postoperative complications related to the given surgical procedure. Follow-up CT scan showed no residual tumor or thrombus in inferior vena cava and pulmonary artery. Echocardiography revealed persistent dilation of right compartments of the heart with good systolic functions of both ventricles. The patient was discharged from hospital in a good condition. CONCLUSION: Surgical removal of renal tumor and tumor thrombus - radical nephrectomy with tumor thrombectomy - can be a curative treatment and can ensure long-term survival of the patient. Depending on the extent of the tumor thrombus, these operations can be performed in different ways - mini-invasive, robotic or open. When open surgery is used, it is possible to perform the procedure with or without extracorporeal circulation (cardiopulmonary bypass - CPB) depending on the extent of the disease.

Impact of the venting via vena cava inferior on the outcome of liver transplantation.

BACKGROUND: The liver transplantation is a standard treatment method for the indicated group of patients with a final hepatic failure. The aim of this paper was to compare two reperfusion methods of implanted liver, non-venting and venting vena cava, and to evaluate the impact of both techniques on the post reperfusion syndrome. METHODS: We compared two groups of patients: non-venting (n = 42) and venting (n = 41). We monitored bilirubin, liver enzymes and hemodynamic changes after reperfusion. We recorded monitored parameters immediately prior to the transplantation, during and after the reperfusion and on the 1st postoperative day. All liver grafts were used from the donors after a brain death. RESULTS: We did not find a statistically significant difference in input monitored parameters. We detected significant changes of pH after reperfusion in both monitored groups. We determined a significantly better saturation in the non-venting group, bigger consumption of fresh frozen plasma and thrombo-concentrate in the non-venting group, a significantly higher value of total bilirubin and a lower value of Quick's time in the non-venting group. CONCLUSION: Venting via vena cava inferior did not impact the perioperative and early postoperative course of liver transplantation in our group of patients. However, further analyses are required (Tab. 2, Fig. 3, Ref. 20).

Substituent Pattern Effects on the Redox Potentials of Quinone-Based Active Materials for Aqueous Redox Flow Batteries.

Quinone-based, aqueous redox flow batteries are a promising technology for large-scale, low-cost energy storage. To understand the influence of substituent and substituent pattern effects of quinone-based derivatives on the redox potential, a screening study was performed that included benzoquinone, naphtaquinone, and anthraquinone derivatives. The order of substituent influence is -OH>-Me/-OMe for decreasing the redox potential and -F<-SO3 - <-CN, -NO2 for increasing the redox potential, which is in agreement with general expectations. We found that the consideration of resonance and inductive effects design strategies of redox-active materials can be extended by the ability of intramolecular hydrogen bond formation, steric hindrance, and energetic differences of conformers for oxidized and reduced species. Due to the complexity and overlap of these effects, theoretical screening studies can provide guidance for the design of new molecular materials. In addition to the redox potential, other parameters such as stability, solubility, and kinetic rate constant or synthetic accessibility are crucial to consider.

Endovascular treatment of aorto-hepatic bypass thrombosis following liver transplantation.

Hepatic artery thrombosis is the most common vascular complication after liver transplantation. Early thrombosis is treated by surgical revascularization; if not feasible, there is need for urgent retransplantation. Late thrombosis is diagnosed mostly when clinical symptoms or graft dysfunction are present, in which case the only possible therapy is retransplantation. We present a case of a young patient with late thrombosis of an aorto-hepatic bypass, in whom we successfully used thrombolytic therapy with stent-graft placement.

Analysis of microscopic bone properties in an osteoporotic sheep model: a combined biomechanics, FE and ToF-SIMS study.

The present study deals with the characterization of bone quality in a sheep model of postmenopausal osteoporosis. Sheep were sham operated ( n = 7), ovariectomized ( n = 6), ovariectomized and treated with deficient diet ( n = 8) or ovariectomized, treated with deficient diet and glucocorticoid injections ( n = 7). The focus of the study is on the microscopic properties at tissue level. Microscopic mechanical properties of osteoporotic bone were evaluated by a combination of biomechanical testing and mathematical modelling. Sample stiffness and strength were determined by compression tests and finite-element analysis of stress states was conducted. From this, an averaged microscopic Young's modulus at tissue level was determined. Trabecular structure as well as mineral and collagen distribution in samples of sheep vertebrae were analysed by micro-computed tomography and time-of-flight secondary ion mass spectrometry. In the osteoporotic sheep model, a disturbed fibril structure in the triple treated group was observed, but bone loss only occurred in form of reduced trabecular number and thickness and cortical decline, while quality of the residual bone was preserved. The preserved bone tissue properties in the osteoporotic sheep model allowed for an estimation of bone strength which behaves similar to the human case.

Influence of texture and grain misorientation on the ionic conduction in multilayered solid electrolytes - interface strain effects in competition with blocking grain boundaries.

Interface strain and its influence on the ionic transport along hetero-interfaces has gained a lot of attention over the last decade and is controversially discussed. We investigate the relaxation of mismatch induced interfacial strain as a function of the degree of orientation/texture of the columnar crystallites and assess the impact on the oxygen ion conductivity in Er2O3/YSZ multilayer systems. Results from X-ray diffraction clearly show, that the width of the strained hetero-interface region increases with an increasing degree of orientation of the crystallites. The combined impact of film texture and strain at the hetero-interfaces of the film on the ionic conductivity however is not easily deduced from these measurements. The samples with the highest degree of orientation, i.e. with only one azimuthal variant, show strong anisotropic electrical properties. In samples with a lower degree of orientation, i.e. samples with a fiber texture, anisotropic properties cannot be detected, possibly due to a geometrical averaging of the electrical properties. The expected strain induced monotonic increase of the ionic conductivity with decreasing layer thickness and thus increasing interfacial influence could only be detected for samples with a fiber texture and a considerable degree of crystallite misorientation. This leads to the important conclusion that the texture and therefore the nature of the grain boundaries and their network influence the ionic conductivity of the multilayer thin films in the same order of magnitude as the misfit induced interface strain. Thus, the potential design of strain-controlled ionic conductors requires additionally the control of the microstructure in terms of grain orientation.

[Experience with hepatoblastoma treatment in small children - the use of preoperative 3D virtual analysis MeVis for liver resections]. / Skúsenosti s liecbou hepatoblastómu u najmensích detí - vyuzitie predoperacnej 3D virtuálnej analýzy MeVis pri resekciách pecene.

INTRODUCTION: Hepatoblastoma is an uncommon but most frequent liver cancer in infants and children. The therapy is complex, including neoadjuvant, surgical, and adjuvant therapy. For surgery, the presence of a specialized surgeon and an anaesthesiologist is required. For planning the surgery, the 3D analysis MeVis is currently available. The objective of the work is the assessment of a group of children operated for a liver hepatoblastoma and the assessment of contribution of a pre-surgery virtual 3D analysis MeVis for a surgeon. METHODS: It represents a retrospective assessment of the operated children for the given diagnosis. Upon confirming the disease, the patients underwent neoadjuvant therapy, and then the MeVis analysis of a liver, a surgery, and an adjuvant therapy. The oncologic treatment was performed according to the SIOPEL recommendations. RESULTS: In the period of 2012 to 2016, we treated 5 infant patients with the diagnosed hepatoblastoma. The children were at the age between 4 and 37 months, 4 girls, 1 boy. The size of tumours according to the SIOPEL classification was PRETEXT II to IV. All children underwent a surgery without any complications and without any signs of post-operative failure of the post-resection remnant of the liver. The functional volume of the post-resection remnant of the liver was between 28%70% according to the MeVis analysis. During the long-term monitoring, one patient underwent lung metastasectomy, all children are currently without any signs of relapse of the disease. CONCLUSION: In case of quick catching and correct management of a hepatoblastoma, the results of therapy are very good. For successful treatment, a surgeon experienced in liver resection, presence of a specialized paediatric anaesthesiologist, and a paediatric oncologist are is required. The exact volumetric analysis MeVis is a contribution for a pre-operational review of the finding, and for the preparation of the surgery. The disease is uncommon, and therefore, the groups of patients are small. Due to that reason, the treatment should be centralized to a specialized department.Key words: hepatoblastoma MeVis volumetry liver resection.

[The use of negative pressure wound therapy in the fixation of split-thickness skin grafts]. / Pouzitie podtlakovej terapie pri fixácii meshovaných volných kozných transplantátov.

INTRODUCTION: Negative pressure wound therapy is one of the latest methods of dealing with complicated healing wounds. It promotes granulation, mechanically attracts the edges of the wound, removes secretions, reduces the number of bacteria in the wound and reduces swelling. In addition to its use to start and enhance the healing process, this method is also important in the fixation of split-thickness skin grafts in non-ideal conditions. The goal of this article is to establish basic indications for negative pressure fixation of meshed split-thickness skin grafts in non-ideal conditions in the wound and to assess the impact of contamination of wounds on engraftment using vacuum therapy. Additional goals are to verify the use of this method of fixation in defects of various etiologies (trauma, ischemia), to optimize and determine the advantages and disadvantages of fixation of grafts using this method in clinical practice, and to evaluate the effectiveness of fixation of meshed split-thickness skin grafts. METHODS: Set of 89 operated patients of both sexes, various ages, etiologies of defects, in non-ideal conditions; statistical evaluation of the percentage of engraftment, depending on the etiology of the defect, microbial contamination and location of the defect. Measured in vivo using a centimeter measure at the point of maximum length and width. RESULTS: Our set of 100% engraftments of StSG included 68 persons, 65 males and 24 females, in the following age groups: up to 30 years 11 persons; 3050 years 19 persons; 5070 years 38 persons; and above 70 years 21 persons, with negative microbial contamination of the defect in 20 cases, contamination with one germ in 33 cases, contamination with two germs in 22 cases and contamination with three germs in 14 cases. We obtained 100% engraftment in 68 cases, 9099% engraftment in 7 cases, 8089% engraftment in 5 cases, 7079% engraftment in 7 cases, and the 6069% and 5059% sets of engraftment were combined because of the low number of patients in this set. 51 of the patients had a traumatic origin of their defect, 22 had an ischemic origin of their defect and 16 had a different origin of their defect. We found a significant relationship between contamination and the percentage of engraftment, as well as dependence between patient age and the percentage of engraftment. CONCLUSION: Negative pressure fixation of meshed split-thickness skin grafts seems to be a convenient method of fixation in patients with defects of various origins in non-ideal conditions; this method increases the percentage of engraftment and apparently reduces the time required for fixation of the graft and the length of hospitalisation. We obtained 100% engraftment of StSG using negative pressure fixation. We concluded that traumatic origin had no effect on the percentage of engraftment, while ischemic origin had a significant effect on engraftment. Also, negative contamination of the defect had a positive effect on StSG engraftment, and contamination wit three microbial germs had a significant negative effect on the percentage of StSG engraftment using negative pressure fixation.Key words: negative pressure therapy - NPWT plastic surgery skin grafts complicated wounds.

Correlation of electrochromic properties and oxidation states in nanocrystalline tungsten trioxide.

Although tungsten trioxide (WO3) has been extensively studied since its electrochromic properties were first discovered, the mechanism responsible for the coloration or bleaching effect is still disputed. New insights into the coloration mechanism of electrochromic, nanocrystalline WO3 are provided in this paper by studying thin WO3 films combining the electrochemical and spectroscopic techniques. By employing in situ UV-Vis transmission spectroscopy at a fixed spectral band pass during electrochemical experiments, such as cyclic voltammetry, a two-step insertion process for both protons and lithium ions is identified, of which one step exhibits a significantly higher coloration efficiency than the other. To obtain a better understanding of the insertion process AxWO3 (A = H, Li,…) thin films were studied at different stages of intercalation using UV-Vis and X-ray photoelectron spectroscopy. The results show that the first step of the intercalation process represents the reduction from initial W(6+) to W(5+) and the second step the reduction of W(5+) to W(4+). We found that the blue coloration of this nanocrystalline tungsten trioxide is mainly due to the presence of W(4+) rather than that of W(5+).

Coherency strain and its effect on ionic conductivity and diffusion in solid electrolytes--an improved model for nanocrystalline thin films and a review of experimental data.

A phenomenological and analytical model for the influence of strain effects on atomic transport in columnar thin films is presented. A model system consisting of two types of crystalline thin films with coherent interfaces is assumed. Biaxial mechanical strain ε0 is caused by lattice misfit of the two phases. The conjoined films consist of columnar crystallites with a small diameter l. Strain relaxation by local elastic deformation, parallel to the hetero-interface, is possible along the columnar grain boundaries. The spatial extent δ0 of the strained hetero-interface regions can be calculated, assuming an exponential decay of the deformation-forces. The effect of the strain field on the local ionic transport in a thin film is then calculated by using the thermodynamic relation between (isostatic) pressure and free activation enthalpy ΔG(#). An expression describing the total ionic transport relative to bulk transport of a thin film or a multilayer as a function of the layer thickness is obtained as an integral average over strained and unstrained regions. The expression depends only on known material constants such as Young modulus Y, Poisson ratio ν and activation volume ΔV(#), which can be combined as dimensionless parameters. The model is successfully used to describe own experimental data from conductivity and diffusion studies. In the second part of the paper a comprehensive literature overview of experimental studies on (fast) ion transport in thin films and multilayers along solid-solid hetero-interfaces is presented. By comparing and reviewing the data the observed interface effects can be classified into three groups: (i) transport along interfaces between extrinsic ionic conductors (and insulator), (ii) transport along an open surface of an extrinsic ionic conductor and (iii) transport along interfaces between intrinsic ionic conductors. The observed effects in these groups differ by about five orders of magnitude in a very consistent way. The modified interface transport in group (i) is most probably caused by strain effects, misfit dislocations or disordered transition regions.

Plasma electrochemistry in ionic liquids: deposition of copper nanoparticles.

We report on the synthesis of copper nanoparticles in two different water- and air-stable ionic liquids using plasma electrochemical deposition. The copper nanoparticles were deposited in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py(1,4)]Tf(2)N) and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]Tf(2)N). To get information on the dimensions of the particles made, we have applied in situ transmission electron microscopy (TEM) (particles in ionic liquid). The chemical composition was investigated by ex situ X-ray photoelectron spectroscopy (XPS). We found that the copper particles produced in [Py(1,4)]Tf(2)N were larger in size compared to the particles obtained in [EMIm] Tf(2)N (roughly 20 vs. 10 nm). The chemical composition of the particle surface differs too. In both cases the particles are partly oxidised leading to a CuO shell, but the particles obtained in [Py(1,4)]Tf(2)N carry a lot of residues from the ionic liquid.

Elastic strain at interfaces and its influence on ionic conductivity in nanoscaled solid electrolyte thin films--theoretical considerations and experimental studies.

Ionic transport in solids parallel to grain or phase boundaries is usually strongly enhanced compared to the bulk. Transport perpendicular to an interface (across an interface) is often much slower. Therefore in modern micro- and nanoscaled devices, a severe influence on the ionic/atomic transport properties can be expected due to the high density of interfaces.Transport processes in boundaries of ionic materials are still not understood on an atomic scale. In most of the studies on ionic materials the interfacial transport properties are explained by the influence of space charge regions. Here we discuss the influence of interfacial strain at semicoherent or coherent heterophase boundaries on ionic transport along these interfaces in ionic materials. A qualitative model is introduced for (untilted and untwisted) hetero phase boundaries. For experimental verification, the interfacial oxygen ionic conductivity of different multilayer systems consisting of cubic ZrO(2) stabilised by aliovalent dopands (YSZ, CSZ) and an insulating oxide is investigated as a function of structural mismatch. Recent results on extremely fast ionic conduction in YSZ/SrTiO(3) thin film systems ("colossal ionic concuctivity at interfaces") is discussed from the viewpoint of strain effects.

Influence of interface structure on mass transport in phase boundaries between different ionic materials: Experimental studies and formal considerations.

ABSTRACT: Internal and external interfaces in solids exhibit completely different transport properties compared to the bulk. Transport parallel to grain or phase boundaries is usually strongly enhanced. Transport perpendicular to an interface is usually blocked, i.e., transport across an interface is often much slower. Due to the high density of interfaces in modern micro- and nanoscaled devices, a severe influence on the total transport properties can be expected. In contrast to diffusion in metal grain boundaries, transport phenomena in boundaries of ionic materials are still less understood. The specific transport properties along metal grain boundaries are explained by structural factors like packing densities or dislocation densities in the interface region. In most studies dealing with ionic materials, the interfacial transport properties are merely explained by the influence of space charge regions. In this study the influence of the interface structure on the interfacial transport properties of ionic materials is discussed in analogy to metallic materials. A qualitative model based on the density of misfit dislocations and on interfacial strain is introduced for (untilted and untwisted) phase boundaries. For experimental verification, the interfacial ionic conductivity of different multilayer systems consisting of stabilised ZrO2 and an insulating oxide is investigated as a funtion of structural mismatch. As predicted by the model, the interfacial conductivity increases when the lattice mismatch is increased.

Ionic conductivity and activation energy for oxygen ion transport in superlattices--the semicoherent multilayer system YSZ (ZrO2 + 9.5 mol% Y2O3)/Y2O3.

The oxygen ion conductivity of YSZ (ZrO(2) + 9.5 mol% Y(2)O(3))/Y(2)O(3) multilayer systems is measured parallel to the interfaces as a function of temperature between 350 and 700 degrees C. The multilayer samples are prepared by pulsed laser deposition (PLD). The film thicknesses, the crystallinity, the texture and the microstructure are investigated by SEM, XRD, HRTEM and SAED. To separate the interface contribution of the total conductivity from the bulk contribution the thickness of the YSZ and Y(2)O(3) layers is varied systematically. The total conductivity of the YSZ films increases when their thickness is decreased from 0.53 microm to 24 nm. It depends linearly on the reciprocal thickness of the individual layers, thus on the number of YSZ/Y(2)O(3) interfaces. This behaviour results from the parallel connection between individual conduction paths in the bulk and the interfacial regions. The activation energy for the ionic conductivity decreases from 1.13 to 0.99 kJ mol(-1) by decreasing the thicknesses of the individual YSZ layers. HRTEM studies show that the YSZ/Y(2)O(3) interfaces are semicoherent. The correlation between interface structure and ionic conduction is discussed.

Control of the surface morphology of solid electrolyte films during field-driven growth in a reactive plasma.

Experiments on the generation of non-equilibrium surface patterns on ion-conducting thin films (AgCl, silver chloride) during field-driven growth in chlorine rf plasmas are reported. The growth experiments are performed in a vacuum flow reactor in the temperature range between 320 K and 450 K, at chlorine gas pressures in the order of 100 Pa, and by applying current densities in the order of 1 mA cm(-2). The surface morphology of product films is documented by scanning electron microscopy and analysed in terms of typical surface patterns. A large variety of different surface morphologies (often finger-like or dendritic) is prepared with a high lateral uniformity and good reproducibility. A theoretical stability criterion is derived on the basis of a linear stability analysis. The model-type experiments confirm this formal stability criterion: (a) The growth of the product surface is morphologically stable, if the plasma exhibits a higher conductivity than the growing solid. (b) The typical wavelength of the surface patterns that are formed during growth is proportional to the reciprocal root of the electric current. (c) The periodicity of the surface patterns decreases when the temperature is increased, and the growth rate of a surface instability grows with increasing temperature. All theoretical predictions are confirmed by corresponding experimental results.

[Vascular complications after pancreatic transplantation]. / Cévní komplikace po transplantaci pankreatu.

Transplantation of pancreas is presently the only way of treating diabetes of the 1st type, capable to secure a long-term normoglycemia. In spite of the fact that the surgical technique and tactics of the whole intervention has been standardized over the last years, surgical complications and more specifically vascular complications still pose a certain risk of the graft loss. The thrombosis of vessels of the transplanted pancreas occurred in our group in 4.1 per cent of cases. The other rare complications included a false aneurysm of the supplying artery and stenosis of the out-coming vein from the pancreatic graft. Both these complications were successfully treated by a radio-invasive approach. A refinement of the surgical technique and the introduction of new immunosuppressive drugs manifests favorably in decreasing occurrence of vascular complications after the transplantation of pancreas.