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Detection of adenosine triphosphate (ATP) by bioluminescence is used, for instance, in the food industry and in hospitals to assess the hygiene status of surfaces. The aim of this laboratory study was to investigate the feasibility of the ATP method for estimating the cleanability of resilient floor coverings from biological soil. The surfaces were worn using a Soiling and Wearing Drum Tester, and soiled and cleaned with an Erichsen Washability and Scrubbing Resistance Tester. In the laboratory test carried out with the bioluminescence method, most of the new and worn floor coverings that were biologically soiled were cleaned efficiently. According to this study, the semiquantitative ATP screening method can be used for hygiene monitoring of flooring materials. No correlation was found between cleanability and contact angles or surface topography measured using a profilometer. However, by revealing local irregularities and damage on surfaces, scanning electron micrographs appeared useful in explaining differences in cleanability.

Diamond-like, tetrahedrally bonded amorphous carbon (ta-C) coating was used to enhance the wear resistance of laboratory-made microstructured poly(vinyl chloride) (PVC) surfaces. Formulation of PVC samples was kept simple; they contained only stabilizer and plasticizer added to PVC. Two sizes of microstructures were imprinted on PVC. Both smooth and microstructured PVC surfaces were coated with amorphous diamond and the surfaces were characterized by spectroscopic ellipsometry, AFM and contact profilometry. In addition, water contact angles were measured. The plasticizer, plasticizer concentration and amorphous carbon coating affected the topography of the microstructure and the water contact angles on surfaces. The ta-C-coated microstructured surfaces were worn with a soiling and wearing drum tester to study their wearing behavior. Surface topographies were measured with a profilometer after wearing studies.

A quantitative radiochemical measuring procedure was used to investigate soil adhesion on laboratory-made polyvinyl chloride (PVC) surfaces. The materials contained different plasticizers and microstructures. Both the quality and amount of plasticizers and the microstructure affected the cleanability of the PVC samples. The surface topography and structures were examined with a contact angle meter, atomic force microscopy (AFM) and a contact profilometer.

The aim of this investigation was to examine the effect of surface topography of different compositions and surface coatings of glazed ceramic tiles on their cleanability. The cleanability was estimated with color measurements. Contact angle measurements were used to describe the surface properties and profilometry and electron microscopy to describe the topography. The effect of additional coatings on the surface properties was compared by applying experimental zirconia and titania coatings as well as a commercial fluoropolymer coating on one of the experimental and all reference glazes. The results show that there were clear differences between the soiling tendencies of the glazes. Generally the topography measurements show that the rougher was ceramic glaze, the more soil adhered on its surface.

Adhesion of soil on glazed surfaces and their cleanability depends on chemical composition, phase composition, and roughness of the surface. The surface can be glossy consisting mainly of a smooth glassy phase. A matt and rough surface consists of a glassy phase and one or more crystalline phases. The origin and composition of the crystalline phases affect the chemical resistance and the cleanability of the surface. Fifteen experimental glossy and matt glazes were soaked in a slightly alkaline cleaning agent solution. The surfaces were spin-coated with sebum, i.e. a soil component typical for sanitary facilities. After wiping out the soil film in a controlled manner, the surface conditions and the soil left were evaluated with colour measurements, SEM/EDXA and COM. The results show that wollastonite-type crystals in the glaze surfaces were attacked in aqueous solutions containing typical cleaning agents. This corrosion led to significant decrease in the cleanability of the surface. The other crystal types observed, i.e. diopside and quartz crystals were not corroded, and the cleanability of glazes containing only these crystals was not changed in the cleaning agent exposures. Also the glassy phase was found to be attacked in some formulations leading to a somewhat decreased cleanability. The repeated soiling and cleaning procedures indicated that soil is accumulated on rough surfaces and surfaces which were clearly corroded by the cleaning agent.

The tendency to soil and cleanability of ten commercial plastic floor coverings: eight vinyl (PVC) floor coverings, one vinyl composite tile and one plastic composite tile, were examined. Floor coverings were soiled with inorganic, organic and biological soil. The cleanability was measured both by bioluminescence of ATP (adenosine triphosphate) and colorimetrically. The surface topography was studied by AFM, SEM and with a profilometer. From the 2D- and 3D-profilometric measurements several characteristic parameters of the surface profiles were extracted. The tendency to soil and cleanability were compared with the characteristics of the surface. A weak correlation was found between roughness and soilability but no correlation between roughness and cleanability. Roughness had no correlation with contact angle.

A new method to study the wear of floor coverings is presented. Surfaces were worn in a drum based on a new standard proposal. A test device called a “hexapod” walks along the floor coverings, which are placed on the wall of the drum containing sand. This walking mimics the real situation better than the current European standard EN 660-2 abrasive wear test for floor coverings. The proposed method was applied to testing the durability of 15 commercial floor coverings. The results were compared with the standard abrasive test EN 660-2. No correlation between the two methods was obtained, showing convincingly that the two tests represent different kinds of wearing mechanisms. Profilometry measurements were performed to obtain information about wearing. Mean waviness did not correlate with wearing.

In this study different substitution methods for the replacement of missing data values were inspected for the use of these cases in a neural network based decision support system for acute appendicitis. The leucocyte count had the greatest number of missing values and was used in the analyses. Four different methods were compared: substituting means, random values, nearest neighbour and a neural network. There were great differences in the substituted leucocyte count values between different methods and only nearest neighbour and neural network agreed about most of the cases. The importance of the substitution method for the final diagnostic classification of the patients by the neural network based decision support system was found to be small.

Four different neural network algorithms, binary adaptive resonance theory (ART1), self-organizing map, learning vector quantization and back-propagation, were compared in the diagnosis of acute appendicitis with different parameter groups. The results show that supervised learning algorithms learning vector quantization and back-propagation were better than unsupervised algorithms in this medical decision making problem. The best results were obtained with the learning vector quantization. The self-organizing map algorithm showed good specificity, but this was in conjunction with lower sensitivity. The best parameter group was found to be the clinical signs. It seems beneficial to design a decision support system which uses these methods in the decision making process.

The aim of this randomized study was to compare the neonatal outcome in infants who have been exposed in utero to indomethacin with that in infants exposed to a β -adrenergic agonist, nylidrin hydrochloride. Eighty pregnant women threatened with preterm labor between 24 and 34 weeks of gestation were enrolled in the study. An intravenous infusion of nylidrin or enterally administered indomethacin was given for a maximum of 72 hours. If preterm labor recurred, all parturient patients were treated with nylidrin. Indomethacin prolonged gestation significantly more than the β-adrenergic agonist (6.6 weeks vs 4.5 weeks; p = 0.04). Ten of the forty-two infants exposed to indomethacin and 2 of the 45 infants exposed to nylidrin had bronchopulmonary dysplasia (24% vs 5%; p = 0.02). Among the 28 infants delivered within 120 hours after the start of treatment, the incidences of respiratory distress syndrome (82% vs 29%; p = 0.02), bronchopulmonary dysplasia (73% vs 6%; p = 0.0006), and necrotizing enterocolitis or focal intestinal perforation (27% vs 0%; p = 0.03) were higher among those exposed to indomethacin than among those exposed to nylidrin. We infer that administration of indomethacin to pregnant women threatened with premature labor is associated with an increased risk of bronchopulmonary dysplasia in their infants if delivery occurs early. (J P EDIATR 1994;124:782-8)

A retrospective follow-up (range 9.4-22 years, mean 13 years) study of 83 patients with grade I-III (WHO) bladder carcinomas was performed. Nuclear area (mean +/- SD 59.7 +/- 18.7 microns2) and the SD of nuclear area (mean +/- SD 19.7 +/- 13.4 microns2) were determined by using morphometric methods. The SD of nuclear area and histopathological grade exhibited a clearly significant relation, the relation between grade and nuclear area was weaker. The number of recurrences in the bladder and the recurrence-free period were not significantly related to histopathological grade, mean nuclear area or SD of nuclear area. The progress in nodal or metastatic stage could be predicted by histopathological grade, mean nuclear area and SD of the nuclear area. Prediction of crude survival, however, was not efficient. When only bladder cancer deaths were included in the analysis, histopathological grade (p less than 0.001), mean nuclear area (p = 0.011) and SD of the nuclear area (p = 0.001) showed a significant relation to survival. Grade II tumors could be divided into two prognostically different groups using nuclear area and SD of the nuclear area as classifiers. The results suggest that morphometric parameters are as good as histopathological grade in predicting long-term prognosis of bladder carcinomas, and better than the histopathological grade in predicting progress in nodal (N) or metastatic (M) stage.

Estimation of mitotic activity by counting the number of mitotic figures per high power fields is subject to many sources of error. The microscope fields vary in size in different microscopes, which makes comparisons arbitrary. Also the areas covered by neoplastic and non-neoplastic tissue in the microscope image vary in different tumors. We found that each microscope could easily be characterized in terms of the size of the microscope field at 40x objective magnification (usually at ocular magnification of 10x). We also found that the number of mitotic figures can be related to the area covered by neoplastic tissue in the microscope field. The resulting index, the volume corrected mitotic index (M/V-index) will express the mitotic activity as the number of mitotic figures per square millimeter of neoplastic tissue in the microscope fields. The M/V-index will not be subject to the variation in volume fractions of neoplastic tissue between different neoplasms. With the M/V-index the mitotic activity as measured in different microscopes can be compared reliably. The value of the method is demonstrated in a series of ovarian tumors.

The DNA ploidy of breast cancer tissue from paraffin blocks was measured by flow cytometry in 122 patients. In this material there was a difference in lymph node involvement and in the presence of distant metastases between diploid and aneuploid tumors. Diploid tumors were smaller than aneuploid tumors. Aneuploid tumors were more common in postmenopausal than in premenopausal women. Near tetraploid tumors were found in older patients rather than tumors with other ploidy patterns. The ploidy pattern was not associated with survival during the mean follow-up of 4.1 years. We specially studied the S-phase fraction (SPF) which was distinctly higher in aneuploid tumors than in diploid tumors. Also near tetraploid, hypertetraploid and multiploid tumors showed higher SPF than diploid tumors. The median of SPF in our material was 8.5%. Positive axillary lymph nodes were found in 32% of the patients who had tumors with an SPF below the median and in 46% of those with tumors above the median (SPF greater than 8.5%). The difference, however, was not statistically significant. In our material the SPF of the tumor did not show a significant association with survival. However, longer follow up time is needed for firm conclusions on the predictive value of cell DNA on survival.

Risk factors associated with coronary heart disease were surveyed in a multicentre study carried out in 1979 among children living in different parts of Finland. The survey included analyses of plasma lipids and cholesteryl ester (CE) fatty acids as well as a dietary interview by a 48-hour recall method. The present report gives the plasma fatty acid compositions obtained from 181 3-year-old and 226 12-year-old children and their relations to dietary factors and other plasma lipids. The mean percentages (±SD) of CE linoleate in the 3- and 12-year-old children were 49.2 ± 5.2 and 51.0 ± 5.0%, respectively. Differences in CE fatty acid composition between the various regions of Finland were relatively small, but there was a trend to higher proportions of polyunsaturated fatty acids in western and urban compared with eastern and rural communities. Among different dietary constituents the daily intake of margarine + oils or butter had the greatest effect on plasma CE fatty acid composition. There was a highly significant positive correlation between the dietary P/S ratio and the percentage of CE linoleate in plasma.

A morphometric study of the coronary arteries of 175 autopsied children showed that stenosing lesions were frequent. The lesions were sometimes very thick even in the newborn, indicating that they can appear rapidly. These changes were partly, due to insudation inside the intimal layer, but the thickening of the whole longitudinal muscle layer was chiefly due to smooth muscle cell proliferation. The topography of the changes was similar to that of arteriosclerosis in later life. A very significant association was found between infections and the formation of a thickened arterial wall ( P It was considered that changes of this kind — although initially partly reversible — may predispose to arteriosclerosis. These observations call for further studies on the correlation between arteriosclerotic heart disease and infections.

We compared the effects of mild hypercholesterolemia and repeated endotoxin infusions on the biochemical composition of aortic intima and inner media of 24 piglets divided into 4 groups 5 days after weaning: controls on normal diet (group I); normal diet and endotoxin (group II); fat-supplemented diet (group III); and fat-supplemented diet and endotoxin (group IV). It was found that mild hypercholesterolemia increased the concentration of arterial esterified cholesterol and the relative amount of the fraction containing chondroitin sulphates A and C in total glycosaminoglycans. Endotoxin infusions partly prevented the increase of serum cholesterol caused by the fat-supplemented diet but had no independent effect on the arterial biochemical composition; nor did they affect the biochemical changes caused by hypercholesterolemia. When the results of all groups were combined, chondroitin sulphates A and C showed a significant positive correlation with the concentration of arterial esterified cholesterol and the percentage of linoleic acid in arterial cholesteryl esters. Serum total cholesterol did not correlate with arterial cholesterol fractions, but the ratio of high density lipoprotein-cholesterol to total serum cholesterol showed a negative association with arterial esterified cholesterol. The present findings indicate that (1) mild hypercholesterolemia is atherogenic in young piglets, and (2) changes in arterial glycosaminoglycan composition might be one of the earliest biochemical alterations in atherogenesis.

The variation sources relevant to a diagnostic morphometric study were analysed. The influence of each source was estimated in two experiments, performed in systems applying computer assisted interactive morphometry. In the first experiment one observer measured the areas of a large number of nuclei in a section from a grade II transitional cell carcinoma of the bladder. In the second experiment two groups of researchers, from Ancona and Kuopio, measured one field from five different samples of transitional cell tumours (including the case of grade II carcinoma). It turned out that pure interobserver variation was responsible for about a half of the total variation present in the diagnostic system. When the variation characteristics of the diagnostic system had been determined, the number of nuclei that had to be measured to reach a defined level of accuracy could be estimated. Such an estimate was also dependent on the predefined expectancy probability of reaching a correct estimate. The study showed that group morphometry (statistical, investigative morphometry) and diagnostic morphometry must be understood as two different approaches in histopathology. By applying group morphometry, good research results can be gathered with cruder measurements than in diagnostic morphometry. Because investigations in group morphometry are more standardized than in diagnostic morphometry, a larger number of structures has to be measured in diagnostic histopathology for the same level of accuracy.

Three cases of radiation-related chronic heart disease are reported. All three patients had been treated for Hodgkin's disease with a mantle technique six to ten years earlier. Ten years after radiation treatment, a 34-year-old woman had dyspnea during exercise. Her heart was enlarged, and an ECG showed a RBBB. An echocardiogram showed pericardial effusion. Right-sided catheterization revealed an infundibular stenosis. A 31-year-old man had chest pain nine years after radiation. An ECG showed complete RBBB and an exercise stress test signs of ischemia; a coronary angiogram showed three proximal stenoses; and an echocardiogram revealed pericardial effusion. A 12-year-old boy had angina pectoris six years after radiation; one year later, he suffered an acute posterior infarction. Two weeks later he died suddenly. An autopsy showed a severe fibrotic and calcified narrowing of the proximal part of the left main coronary artery. Regardless of the patient's age, radiation-related cardiac complications must be kept in mind. Echocardiograms and, in cases of chest pain, exercise stress tests should be a part of routine postradiation follow-up.

E. Coli endotoxin was administered to 6 piglets from a litter of 10. Three days after the endotoxin stimulus 3 piglets showed definitive morphological evidence of endothelial damage to their left coronary artery. The proximal parts of the coronary artery were severely damaged. In scanning electron microscopy, the changes varied from disappearance of the microvilli to complete exfoliation of the endothelial cells. In cases of severe endothelial cell damage transmission electron microscopy revealed severe changes or even signs of cell death in the inner medial smooth muscle cells. Only of the piglets died prematurely. We are sufficiently encouraged to continue testing the theory that repeated endothelial cell damage initiates stenosing lesions in the coronary arteries.