The effect of bilirubin on long-term mortality in patients with chronic total coronary occlusion.

AIM: We intended to investigate the association of bilirubin with total mortality in patients with chronic total coronary occlusion (CTO). METHODS: We included 172 patients who underwent coronary angiography due to stable angina pectoris and had CTO. We checked the viability of patients after 9 years of follow-up. RESULTS: Direct bilirubin levels were significantly lower in the non-viable group. We revealed age (OR = 1.045, 95% C.I: 1.009‒1.083; p = 0.015) and direct bilirubin concentrations (OR = 0.029, 95% C.I: 0.002‒0.435; p = 0.029) as independent predictors of mortality. Direct bilirubin value of > 0.2 mg/dL was associated with decreased mortality with a sensitivity of 85 %, and a specificity of 46 %. CONCLUSION: Serum direct bilirubin concentrations independently predict total mortality in patients with chronic total occlusion over 9 years of follow-up (Tab. 1, Fig. 2, Ref. 23).

Is SCUBE1 helpful to predict the arterial thrombotic risk in patients with multi-ple myeloma: a preliminary study.

BACKGROUND: Signal peptide-CUB-EGF-like domain-containing protein 1 (SCUBE1) is expressed in vascular endothelium and human platelets. SCUBE1 levels are increased in acute arterial thrombosis. Multiple myeloma patients are also at increased risk of arterial thrombotic events. This study aimed to measure SCUBE1 levels in newly diagnosed multiple myeloma patients and to define whether SCUBE1 could be a useful marker determining the arterial thrombotic risk. METHODS:   SCUBE1 levels of 32 newly diagnosed multiple myeloma patients and 41 healthy control subjects were measured by enzyme-linked immunosorbent assay. RESULTS: Plasma SCUBE1 levels of multiple myeloma patients and control subjects were 6.22 ± 0.9 and 7.95 ± 1.1 ng/ml, respectively. In the patient group, SCUBE1 levels were significantly lower compared to control subjects (p <0.001). CONCLUSIONS: SCUBE1 level measuring does not help to predict the arterial thrombotic risk in multiple myeloma patients. The significantly lower levels of SCUBE1 in multiple myeloma patients are likely to be due to defective platelets and/or increased TNF-α cytokines and is another proof of platelet dysfunction seen in these patients. HIPPOKRATIA 2019, 23(1): 21-24.

Metallic molybdenum disulfide nanosheet-based electrochemical actuators.

Actuators that convert electrical energy to mechanical energy are useful in a wide variety of electromechanical systems and in robotics, with applications such as steerable catheters, adaptive wings for aircraft and drag-reducing wind turbines. Actuation systems can be based on various stimuli, such as heat, solvent adsorption/desorption, or electrochemical action (in systems such as carbon nanotube electrodes, graphite electrodes, polymer electrodes and metals). Here we demonstrate that the dynamic expansion and contraction of electrode films formed by restacking chemically exfoliated nanosheets of two-dimensional metallic molybdenum disulfide (MoS2) on thin plastic substrates can generate substantial mechanical forces. These films are capable of lifting masses that are more than 150 times that of the electrode over several millimetres and for hundreds of cycles. Specifically, the MoS2 films are able to generate mechanical stresses of about 17 megapascals-higher than mammalian muscle (about 0.3 megapascals) and comparable to ceramic piezoelectric actuators (about 40 megapascals)-and strains of about 0.6 per cent, operating at frequencies up to 1 hertz. The actuation performance is attributed to the high electrical conductivity of the metallic 1T phase of MoS2 nanosheets, the elastic modulus of restacked MoS2 layers (2 to 4 gigapascals) and fast proton diffusion between the nanosheets. These results could lead to new electrochemical actuators for high-strain and high-frequency applications.

The use of artificial neural network for prediction of dissolution kinetics.

Colemanite is a preferred boron mineral in industry, such as boric acid production, fabrication of heat resistant glass, and cleaning agents. Dissolution of the mineral is one of the most important processes for these industries. In this study, dissolution of colemanite was examined in water saturated with carbon dioxide solutions. Also, prediction of dissolution rate was determined using artificial neural networks (ANNs) which are based on the multilayered perceptron. Reaction temperature, total pressure, stirring speed, solid/liquid ratio, particle size, and reaction time were selected as input parameters to predict the dissolution rate. Experimental dataset was used to train multilayer perceptron (MLP) networks to allow for prediction of dissolution kinetics. Developing ANNs has provided highly accurate predictions in comparison with an obtained mathematical model used through regression method. We conclude that ANNs may be a preferred alternative approach instead of conventional statistical methods for prediction of boron minerals.

(K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 ferroelectric ceramics.

Recent progress in (K0.44, Na0.52, Li0.04)O3-based ceramics (KNN) with special emphasis on(K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 (KNN-LT-LS) is reviewed concisely. The base KNN and its compositional derivatives are analyzed in terms of dopant-property relationships, which are then extended to the ternary derivatives. The effects of processing conditions such as humidity, precursor purity, and oxygen partial pressure during sintering are elaborated on from a phenomenological perspective. It is also shown that the spontaneous polarization is sensitive to the processing route chosen for synthesis (mixed oxide versus perovskite routes). Special attention is devoted to the discussion of the morphotropic phase boundary (MPB) dilemma in the KNN-LT-LS system, where it is shown that the origin of high piezoelectric activity is actually due to a polymorphic transition at room temperature. It is shown that prototype transducers based on pure and 1 mol% Ba2+ doped KNN-LT-LS exhibit performance metrics comparable to those fabricated using PZT-5H. Overall, KNNLT- LS ceramics show great promise for lead-free applications, although issues such as temperature dependence of properties and strong sensitivity to processing conditions remain as the 2 major challenges.

Piezoelectric-electrostrictive monolithic bi-layer composite flextensional actuator.

We propose a new type of flextensional actuator comprised of an electromechanically active element which is a piezoelectric-electrostrictive monolithic bi-layer composite (PE-MBLC) capped by truncated thin brass sheets. The PE-MBLC contains equal amounts of 0.65[Pb(Mg(1/3)Nb(2/3))O(3)]-0.35PbTiO(3) and 0.9[Pb(Mg(1/3)Nb(2/3))O(3)]-0.1PbTiO(3) by volume, and is obtained by a co-sintering process. With applied E(max) = 10 kV/cm unipolar drive, the maximum axial displacement (u(33)) produced by the uncapped and capped PE-MBLC is 11 and 21 microm, respectively. The hysteresis in unipolar u(33) at 0.5 E(max) is 4.6% for the uncapped PE-MBLC, while that for the capped one is 11%. Under bipolar excitation, the maximum u(33) for uncapped is 11.6 microm at +E(max) and 6.6 microm at +E(max) with an asymmetry factor (zeta) of 1.75 for which u(33) < 0 for all E < 0. Under bipolar excitation, the maximum u(33) at +E(max) for the capped PE-MBLC is 19 microm while that for -E(max) is 8 microm with zeta = 2.4, for which u(33) > 0 at -E(max) but is smaller than the u(33) at +E(max). The origins of the observed asymmetry in u(33) are discussed in the context of symmetry superposition and deformation mechanics of the endcaps.

The effects of heparin on DLD-1 colon cancer cell line.

BACKGROUND: Patients with cancer are frequently treated with anticoagulants, including heparin, to prevent or to treat the deep vein thrombosis. It has been indicated that heparin affects the survival of patients with cancer. Also, the apoptotic and antiproliferative effects of heparin on some cancers has been demonstrated. Experimental studies support the hypothesis that cancer progression can be influenced by heparin, but the results of these studies are not conclusive. OBJECTIVES: We planned to investigate the effects of different concentrations of heparin in the colon cancer cell line DLD-1. METHODS: This study was done by the addition of heparin in different doses into colon cancer cell line DLD-1 in vitro. After an incubation period of 72 hours, study and control groups were evaluated for viable cell count, percentage of proliferating index and apopitosis percentage. RESULTS: The result of the viable cell count in the second and third study groups (98.35+/-27.3, 97.23+/-39.38) were low compared to the control group. The results of the proliferative index of study groups (46.47+/-10.44, 47.23+/-12.03, 45.55+/-14.2) were higher than the control group (40.62+/-9.28). The results of apoptosis in study groups (14.35+/-1.93, 16.47+/-7.25, 13.56+/-5.66) were lower compared to the control group (22.17+/-15.9). But these results were not statistically significant. CONCLUSION: Heparin has no significant anti-proliferative and apoptotic effects on colon cancer cells in vitro. Therefore, for clinical applications, more advanced studies are needed to examine the effect of heparin on colon cancer (Tab. 3, Fig. 3, Ref. 25). Full Text (Free, PDF) www.bmj.sk.

Paraelectric thin films by nanoscale engineering of epitaxy and planar anisotropy for microwave phase shifter applications.

Epitaxial and (110) oriented paraelectric thin films of Ba0.60Sro.40TiO3 were grown on (100) oriented NdGaO3 orthorhombic substrates, and the nonlinear dielectric properties were studied at 10 GHz along selected in-plane crystallographic directions in the film thickness range of 25-1200 nm. The measured dielectric properties show strong residual strain and in-plane directional dependence. For instance, the in-plane relative permittivity is found to vary from as much as 500 to 150 along [110] and [001], respectively, in the 600 nm film. Tunability was found to vary from as much as 54% to 20% in all films and directions. In a given film, the best tunability is observed along the compressed axis in a mixed strain state, 54% along [110] in the 600 nm film. It is shown that, by nanoscale manipulation of epitaxy and planar anisotropy, the return loss and phase shift in a paraelectric can be tuned over a rather wide range. The approach presented herein opens avenues for obtaining various degrees of phase shift on the same film, enabling one with an additional degree of freedom in device design and fabrication as well as multifunctionality.

The effects of VEGF and VEGFR-2 on survival in patients with gastric cancer.

Prognostic criteria of the patients with gastric cancer are of critical importance in their management and follow-up. Angiogenesis is essential for the growth and metastasis of solid tumors. Tumor angiogenesis is a multi-step interactive process, and vascular endothelial growth factor (VEGF) and its receptors have a major role in tumor angiogenesis. Thus, we investigated the effects of VEGF and VEGF receptor-2 (VEGFR-2, KDR) on survival in patients with gastric cancer. We analyzed 51 patients who had undergone total or subtotal gastric resection. The patients were divided into two subgroups according to their VEGF and VEGFR-2 (KDR) expression in resected specimens. There was no significant difference between sex, surgical method, lymph node metastasis, serosal invasion, hematogenous metastasis, chemotherapy status of the two subgroups. Mean follow-up time was 24.22 +/- 15.38 months. We found the survival rates of the patients with VEGF positive tumors to be significantly shorter than those of the patients with VEGF negative tumors. There was no significant difference between the survival rates of VEGFR-2 (KDR) positive and negative patients. It was established that the presence of VEGF expression was significantly associated with the short survival rates in patients with gastric cancer. Analysis of VEGF expression in resected specimens may provide additional guidance in determining the prognosis of such patients. If more extensive studies confirm the significance of VEGF and its receptors in gastric cancer, new therapeutic approaches targeting VEGF and its receptors may be considered in gastric cancer management.

Piezoelectric composites for sensor and actuator applications.

In the last 25 years, piezoelectric ceramic-polymer composites have been conceptualized, prototyped, fabricated, and implemented in an array of applications encompassing medical imaging and military missions, among others. A detailed snapshot of the materials used, and a detailed account of the major innovative methods developed in making various piezoelectric ceramic-polymer composites are presented. The salient aspects of processing of such composites are summarized, and structure-processing-property relations are described using connectivity as the unifying central concept. Computer-aided design (CAD)-based fabrication methods, which result in composites whose structural complexity surpass that of composites obtained with traditional methods, are described to introduce the reader to novel concepts in processing of piezocomposites. A brief survey of some recent advances made in modeling of (0-3), (1-3), and (2-2) composites also is provided.

Electrostrictive properties of nanosize PbTiO(3).

Properties of nanosize PbTiO(3) are discussed from the standpoint of the effects of crystallite size on electrostrictive behavior. Experimental results based on crystallite size-dependent primary and secondary order parameters (spontaneous polarization and strain) show that the critical crystallite size (CCS) for the stabilization of the cubic paraelectric phase at 298 K is around 15 nm. The CCS inversely scales with the cubic-tetragonal transition temperature (T(tr)). Electrostrictive coefficients exhibit an order of magnitude increase at 28 nm, which is attributed to the anharmonicity of the perovskite lattice. First order calculations indicate that the increase in the electrostrictive coefficients offsets the decrease in spontaneous polarization and results in an increase in piezoelectric moduli suggesting that piezoelectric activity could, in principle, be observed in the nanosize regime.