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.

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.

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).

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.

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.

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

We investigate the relaxation of mismatch induced interface strain as a function of the texture and its influence on the ionic conductivity in YSZ/Er₂O₃ multilayer thin films.

Effect of Smoking on Development of New Onset Diabetes Mellitus after Transplantation (NODAT) of Kidney

Purpose: Cigarette smoking has adverse effects on kidney transplant recipients, causing cardiovascular disease, kidney function impairment, and cancer. New onset diabetes mellitus after transplantation (NODAT) represents serious complication of transplantation of solid organs.

Methods: In the group of 252 patients after kidney transplantation, we identified smokers and current non-smokers (the patient who has not been smoking or who is ex smoker) for the period of minimum 24 months. In the monitored period of 12 months after transplantation, we detected presence of NODAT in both groups. The group contained only those patients who did not have diabetes mellitus (of type 1 and 2) at the time of kidney transplantation.

Results: The group of smokers was composed of 88 patients (34.9 %) and non-smokers 164 patients (65.1 %). The average age of smokers was 52 years ± 12.4, and of current non-smokers it was 44.8 years ± 12.8 (P < 0.0001). The smokers had significantly lower body mass index (BMI) at the time of kidney transplantation (P = 0.0059) and also 12 months after transplantation (P = 0.0069), lower weight gain 12 months after transplantation (P = 0.0220) and larger waist circumference 12 months after transplantation (P < 0.0001).

Conclusion: In our group, smoking had no effect on development of NODAT, the smokers had lower values of BMI and waist circumference, however, the guideline development group feels that, as for the general population, success of smoking cessation can be enhanced by offering structured smoking cessation programs.

[The use of negative pressure wound therapy in the fixation of split-thickness skin grafts]

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.

[Experience with hepatoblastoma treatment in small children - the use of preoperative 3D virtual analysis MeVis for liver resections]

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.

Combining two redox active rare earth elements for oxygen storage – electrical properties and defect chemistry of ceria–praseodymia single crystals

The electrochemical properties of (Ce,Pr)O₂ single crystals were characterized to obtain reference data for the bulk system.

Role of the Three-Phase Boundary of the Platinum-Support Interface in Catalysis: A Model Catalyst Kinetic Study

A series of microstructured, supported platinum (Pt) catalyst films (supported on single-crystal yttria-stabilized zirconia) and an appropriate Pt catalyst reference system (supported on single-crystal alumina) were fabricated using pulsed laser deposition and ion-beam etching. The thin films exhibit area-specific lengths of the three-phase boundary (length of three-phase boundary between the Pt, support, and gas phase divided by the superficial area of the sample) that vary over 4 orders of magnitude from 4.5 × 10² to 4.9 × 10⁶ m m^–2, equivalent to structural length scales of 0.2 μm to approximately 9000 μm. The catalyst films have been characterized using X-ray diffraction, atomic force microscopy, high-resolution scanning electron microscopy, and catalytic activity tests employing the carbon monoxide oxidation reaction. When Pt is supported on yttria-stabilized zirconia, the reaction rate clearly depends upon the area-specific length of the three-phase boundary, l(tpb). A similar relationship is not observed when Pt is supported on alumina. We suggest that the presence of the three-phase boundary provides an extra channel of oxygen supply to the Pt through diffusion in or on the yttria-stabilized zirconia support coupled with surface diffusion across the Pt.

YSZ thin films with minimized grain boundary resistivity

The grain boundary resistance of nano-columnar yttria-stabilized zirconia thin films is almost completely eliminated near the film–substrate interface through substrate induced magnesium doping.

Graphene mediated improved sodium storage in nanocrystalline anatase TiO2 for sodium ion batteries with ether electrolyte

Synergy of graphene and diglyme electrolyte in significantly improving the sodium insertion electrochemistry of nanocrystalline titanium dioxide is demonstrated.

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.

From lithium to sodium: cell chemistry of room temperature sodium-air and sodium-sulfur batteries

Research devoted to room temperature lithium-sulfur (Li/S8) and lithium-oxygen (Li/O2) batteries has significantly increased over the past ten years. The race to develop such cell systems is mainly motivated by the very high theoretical energy density and the abundance of sulfur and oxygen. The cell chemistry, however, is complex, and progress toward practical device development remains hampered by some fundamental key issues, which are currently being tackled by numerous approaches. Quite surprisingly, not much is known about the analogous sodium-based battery systems, although the already commercialized, high-temperature Na/S8 and Na/NiCl2 batteries suggest that a rechargeable battery based on sodium is feasible on a large scale. Moreover, the natural abundance of sodium is an attractive benefit for the development of batteries based on low cost components. This review provides a summary of the state-of-the-art knowledge on lithium-sulfur and lithium-oxygen batteries and a direct comparison with the analogous sodium systems. The general properties, major benefits and challenges, recent strategies for performance improvements and general guidelines for further development are summarized and critically discussed. In general, the substitution of lithium for sodium has a strong impact on the overall properties of the cell reaction and differences in ion transport, phase stability, electrode potential, energy density, etc. can be thus expected. Whether these differences will benefit a more reversible cell chemistry is still an open question, but some of the first reports on room temperature Na/S8 and Na/O2 cells already show some exciting differences as compared to the established Li/S8 and Li/O2 systems.

Comment on “How to interpret Onsager cross terms in mixed ionic electronic conductors” by I. Riess, Phys. Chem. Chem. Phys., 2014,16, 22513

Onsager cross coefficients account for the interaction of ionic and electronic fluxes in mixed conductors.

Correlation of electrochromic properties and oxidation states in nanocrystalline tungsten trioxide

In nanocrystalline tungsten trioxide, the main coloration change can be attributed to the formation of W⁴⁺.

Applicability of ToF-SIMS for monitoring compositional changes in bone in a long-term animal model

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a well-established technique in material sciences but has not yet been widely explored for implementation in life sciences. Here, we demonstrate the applicability and advantages of ToF-SIMS analysis for the study of minerals and biomolecules in osseous tissue. The locally resolved analysis of fragment ions deriving from the sample surface enables imaging and differentiation of bone tissue and facilitates histology on non-stained cross sections. In a rat model, bilateral ovariectomy combined with either a multi-deficiency diet or steroid treatment was carried out to create osteoporotic conditions. We focused our study on the Ca content of the mineralized tissue and monitored its decline. Calcium mass images of cross sections show the progressive degenerative changes in the bone. We observed a decreased Ca concentration in the edge region of the trabeculae and a decline in the Ca/P ratio. Additionally, we focused on the non-mineralized matrix and identified fragment ions that are characteristic for the collagen matrix. We observed trabeculae with wide ranges of non-mineralized collagen for the diet group owing to an impaired mineralization process. Here, the advantage of coeval monitoring of collagen and minerals indicated an osteomalacic model rather than an osteoporotic one.

An EMF cell with a nitrogen solid electrolyte--on the transference of nitrogen ions in yttria-stabilized zirconia

The mobility and electrochemical activity of nitrogen inside and/or at the surface of ionic compounds is of fundamental, as well as of possibly practical, relevance. In order to better understand the role of nitrogen anions in solid electrolytes, we measured the transference number of nitrogen in yttria-stabilized zirconia (YSZ) by a concentration cell technique as a function of oxygen activity at different temperatures in the range of 1023 ≤T/K≤ 1123. YSZ doped with 1.9 wt% of N (YSZ:N) turned out to have an appreciable nitrogen transference number, which increased from 0 to 0.1 with decreasing oxygen activity in the range of -20 < log a(O(2)) < -14. The stability of N in YSZ:N, however, has yet to be elucidated under oxidizing conditions.

Mesoporous TiO(2): comparison of classical sol-gel and nanoparticle based photoelectrodes for the water splitting reaction

This paper describes a systematic comparison of the photoelectrochemical properties of mesoporous TiO(2) films prepared by the two most prevalent templating methods: The use of preformed, crystalline nanoparticles is generally considered advantageous compared to the usage of molecular precursors such as TiCl(4), since the latter requires a separate heat treatment at elevated temperature to induce crystallization. However, our photoelectrochemical experiments clearly show that sol-gel derived mesoporous TiO(2) films cause an about 10 times higher efficiency for the water splitting reaction than their counterparts obtained from crystalline TiO(2) nanoparticles. This result indicates that for electrochemical applications the performance of nanoparticle-based metal oxide films might suffer from insufficient electronic connectivity.

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.

Graphical abstract

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.