Oxygen plasma functionalization of parylene C coating for implants surface: nanotopography and active sites for drug anchoring.

The effect of oxygen plasma treatment (t=0.1-60 min, pO2=0.2 mbar, P=50 W) of parylene C implant surface coating was investigated in order to check its influence on morphology (SEM, AFM observations), chemical composition (XPS analysis), hydrophilicity (contact angle measurements) and biocompatibility (MG-63 cell line and Staphylococcus aureus 24167 DSM adhesion screening). The modification procedure leads to oxygen insertion (up to 20 at.%) into the polymer matrix and together with surface topography changes has a dramatic impact on wettability (change of contact angle from θ=78±2 to θ=33±1.9 for unmodified and 60 min treated sample, respectively). As a result, the hydrophilic surface of modified parylene C promotes MG-63 cells growth and at the same time does not influence S. aureus adhesion. The obtained results clearly show that the plasma treatment of parylene C surface provides suitable polar groups (C=O, C-O, O-C=O, C-O-O and O-C(O)-O) for further development of the coating functionality.

Microstructure evolution in hot worked steel after heating to semi-solid state.

Metal alloys can be formed successfully in a partially liquid state if they display a particular globular microstructure. The article presents an analysis of a study carried out of the development, by means of the strain-induced melt-activated method, of such a microstructure for an X210CrW12 steel. Hot rolled samples, with subsequent cooling, were heated to the temperature range at which the liquid and solid phases coexist in the material. The spheroidal shapes for solid particles, required for semi-solid processing, were found. The investigations were carried out using scanning electron microscopy in combination with energy dispersive spectroscopy.

Quantitative misorientation characteristics of interphase boundaries in composites.

Specific crystallographic correlations between neighbouring grains in composites were established by the use of selected area electron diffraction in the transmission electron microscope. However, it was the development of orientation mapping techniques that made it possible to obtain a quantitative description of the distribution of boundaries between the grains of both the same phase and different phases. This study shows that orientation topography measurements made by electron backscatter diffraction in the scanning electron microscope allowed determination of the crystallographic relationships between grains of different phases. An alumina-based composite with a content of 10 vol% tungsten carbide was chosen for investigations. Misorientation distribution functions were calculated to describe the distribution density of misorientations with respect to the nearest neighbouring measured point located in the grain of the second phase. The analysis of misorientation distribution functions permitted the evaluation of preferences for some special crystallographic correlations between the grains of composite matrix and inclusions as well as shares of interphase boundaries characterized by those correlations.

Liver regeneration after anatomical resections.

BACKGROUND: The authors present the results of investigation of liver regeneration after partial parenchyma resection. MATERIAL AND METHODS: 20 patients (16 females, 4 male) aged 31-67 years were operated on because of metastatic colon cancer (7 cases), cavernous hemangioma (6 cases), hepatocellular carcinoma (1), alveococcosis (2), metastases of malignant melanoma (1), gall bladder carcinoma (1), FNH (1) and mucous cystadenocarcinoma (1). The resection according to anatomical segments by Couinaud were performed. Spiral CTs including liver volumetry were taken before and 30 days after the operation. on the 7-th day after the surgery, liver biopsy was performed and the material was examined under light and electron microscope. RESULTS: There was no postoperative mortality. We observed transient elevation of transaminases, bilirubin levels and decrease of albumin level. Control spiral CT revealed increased liver volume in 15 cases (75 percent). In 16 cases (80 percent), electron microscopy investigations showed regeneration of the liver (mitotic figures). CONCLUSIONS: Our material shows that hyperplasia as well as blood vessel and bile duct neogenesis play a very important role in liver regeneration process.

Effects of calcitonin and calcitonin gene-related peptide on 3H-thymidine incorporation into DNA of rat thyroid lobes in vitro.

The effects of a 4 h incubation of rat thyroid lobes, in the presence of calcitonin (CT) and calcitonin gene-related peptide (CGRP) on the incorporation of 3H-thymidine into DNA, were investigated. In other groups the thyroid lobes were incubated during exposure to CT and thyrotropin (TSH), and to CGRP together with TSH. All concentrations of CT (10(-6)-10(-8) M) revealed a tendency towards lowering 3H-thymidine uptake, but the effect was not statistically significant. The influence of CGRP was dose-dependent; the lowest concentration of CGRP (10(-9) M) significantly enhanced DNA synthesis in the incubated rat thyroids; an intermediate dose of the peptide (10(-8) M) had no effect, while the highest concentration of CGRP (10(-7) M) decreased 3H-thymidine incorporation. Calcitonin (10(-7) M), as well as CGRP (10(-8) M), suppressed the stimulatory effect of TSH on 3H-thymidine incorporation.

[Morphologic evaluation of coronary thrombosis in the course of recent myocardial infarction]. / Ocena morfologiczna zakrzepicy tetnic wiencowych w przebiegu swiezego zawalu miesnia serca.

Post-mortem studies of 50 cases of death in the course of recent myocardial infarction were made to analyse relations between coronary thrombosis and myocardial necrosis. We assessed and compared severity of necrotic changes in the myocardium in relation to thrombotic changes in the coronary vessels. Our results show an enhancement and evolution of thrombotic changes with time elapsing from the infarct completion and possible causal relations between a thrombus and infarct.

Measurement of autoantibodies against human eye muscle plasma membranes in Graves' ophthalmopathy.

Antibodies that reacted with plasma membranes of human eye muscle but showed no binding to plasma membranes of human skeletal muscle were identified in serum of patients with Graves' ophthalmopathy. Rabbit antithyroglobulin serum at a dilution of 1 X 10(-3) to 20 X 10(-3) had no effect on the binding of these antibodies to eye muscle membrane antigens. There was no correlation between antihuman eye muscle plasma membrane antibodies and antihuman thyroid membrane antibodies or antibodies against thyroglobulin. It is suggested that specific antibodies against eye muscle membranes are present in Graves' ophthalmopathy and that this disease might represent a distinct autoimmune disorder.

Simple and sensitive method for estimation of antithyroid plasma membrane antibodies in the serum of patients with autoimmune thyroid diseases; comparison with other assays.

The ability of protein A from Staphylococcus aureus to interact with Fc fragments of IgG was used to estimate the antithyroid plasma membrane antibodies in sera of patients with Graves' disease. The results were expressed as an antithyroid plasma membrane antibodies (ATMA) index. The ATMA index estimated in 60 healthy blood donors varied from 0.57 to 1.28, with a mean value of 0.99, SD theta 0.20. The ATMA index in hyperthyroid untreated Graves' disease varied from 1.80 to 8.0, with a mean value of 4.7. Autoantibody binding to thyroid plasma membranes could be inhibited by (Fab)2 fragments obtained from the serum of patients with Graves' disease but not by (Fab)2 fragments obtained from the serum of healthy blood donors. The influence of rabbit antithyroglobulin and antimicrosomal antibodies on the ATMA index estimation has been evaluated. The ATMA index estimation was compared with the thyrotrophin binding inhibiting immunoglobulins (TBII) index and with the adenyl cyclase stimulating activity of immunoglobulins obtained from 92 hyperthyroid Graves' patients. The ATMA index was positive in 97%, the TBII index in 62% and TSI in 35% of cases. This method using protein A could also be used for estimation of ATMA in other autoimmune thyroid disorders.

Influence of antiganglioside antibodies on thyrotrophin binding and adenyl cyclase activity of thyroid plasma membranes.

Antibovine thyroid ganglioside antibodies developed in rabbits inhibit thyrotrophin binding to human thyroid plasma membranes. These antibodies are specific for gangliosides as was shown by the liposome agglutination technique. Antiganglioside antibodies did not stimulate basal adenyl cyclase activity in bovine thyroid plasma membranes, but most antiganglioside antibodies inhibit the activity of thyrotrophin stimulated adenyl cyclase. Antiganglioside antibodies react well with bovine thyroid plasma membranes and have considerable cross-reactivity with porcine and human thyroid plasma membranes. Rabbits which develop antiganglioside antibodies after some time have detectable levels of autoantithyroglobulin antibodies in their serum although the preparation used for imminisation did not contain any thyroglobulin or protein material.

[Interdependence between hormonal disorders, stage of development and degree of malignancy of prostatic cancer. 1]. / L'interdépendance entre les troubles hormonaux, le stade d'évolution et le degré de malignité du cancer de la glande prostatique. Première partie.

The aim of this study was to determine whether in human clinical practice destruction of the prostate gland by a malignant process is accompanied by a fall in serum testosterone and dihydrotestosterone levels. Mean serum testosterone and dihydrotestosterone levels were significantly lower and LH levels notably higher in patients with metastases than in those without metastases. No notable differences were found between serum testosterone and dihydrotestosterone levels in relation to the degree of malignancy of the tumours. Concentrations of relatively inactive androgens (DHA and delta-4-androstenedione) in the serum were normal. The fall in serum concentration levels with later increase in LH levels is probably caused by malignant destruction of the prostate gland.