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R Ettlin

Publications and source records attributed to R Ettlin.

12 recordsLinked to original sources
PubMed1991

Some fundamental aspects of morphometry in clinical pathology, demonstrated on a simple, multipurpose analysis system.

The aim of this study was (1) to investigate the value of morphometry, (2) to fix a set of parameters suitable for analyzing diagnostic problems, and (3) to create a general strategy for data storage and for user-friendly data management. The intrinsic value of morphometry lies in the fact that in contrast to other morphologic methods, it permits the presentation of findings in the form of numbers. The following set of morphometric parameters, in the broad sense of the term morphometry, is standard in our laboratory: planimetric parameters (shape descriptors), parameters of the gray value histogram (descriptors of the general gray value distribution), texture parameters (descriptors of the correlation between various image segments), invariant moments (descriptors of the size and localization of textural image segments) and densitometric parameters. The introduction of morphometric procedures into the daily routine is facilitated if data registration and evaluation are performed separately. Original data generated by direct measurement are primary or raw data, which are stored as such. In a separate, second step these raw data are used to compare more or less complex morphometric parameters, which are called "secondary data". A system designed for separate data registration and evaluation can easily be adapted to new methodologic developments. For instance, primary data on objects (gray values, coordinates of the contour) measured one time in the past can be reused at any other time for computing new features from these data. This procedure is comparable to the possibilities in immunohistochemical staining: new immunohistochemical stains can be applied to newly prepared sections of old tissue blocks.

Computer Communication Networks↗
PubMed1991

The significance of morphometric methods in cytologic diagnostics: differentiation between mesothelial cells, mesothelioma cells and metastatic adenocarcinoma cells in pleural effusions with special emphasis on chromatin texture.

Opinions differ widely as to the value of morphometric techniques for differentiating between mesothelial cells, mesothelioma cells and metastatic adenocarcinoma cells in pleural effusions. The significance of the changes in the chromatin structure to differentiate between these three cell types was stressed by various scientific groups only qualitatively, and until now no group has used digital methods to quantify chromatin structures. The controversy about the value of morphometric methods was the reason for conducting the following study. We wanted to investigate (i) the importance of various planimetric and texture parameters as well as invariant moments as morphometric discriminators; and (ii) to set up a data structure to make possible the further diagnostic use of the multivariate morphometric analyses method for other applications. The present findings show that nuclear size and form are not the decisive factors in differentiating between reactive cells and mesothelioma cells, but pixel related texture parameters and invariant moments are. All parameter types used showed differences between reactive cells and cells of adenocarcinoma metastases. Invariant moments and shape descriptors, but not texture parameters are used to discriminate between mesothelioma cells and cells of adenocarcinoma metastases.

Adenocarcinoma↗
PubMed1990

[Prerequisites for the application of statical morphometry in diagnostics].

The aims of the present paper were: 1. to test a set of parameters suitable for quantifying morphological features; 2. to create a generally valuable strategy for data storage and for a user friendly data management; 3. to examine the parameter set and the conception for an optimal data management by the quantification of cytological specimens of pleural effusions. The significance of a distinction between "primary parameters" (data directly captured during the measurement) and "secondary data" (data calculated from the primary data) is explained. In the first step of classification of the cytological specimens 81.8% of the patients with reactive alterations of mesothelial cells (n = 11) and 100% of the patients with tumours (mesotheliomas and metastasis of adenocarcinomas) (n = 19) were correctly classified with the aid of a little "expert system". In the second step (discrimination between mesotheliomas (n = 6) and metastasis of adenocarcinomas (n = 13] all patients were correctly classified.

Cytodiagnosis↗
PubMed1989

A simple "expert system" for morphometric evaluation of cells in pleural effusions.

Quantitation in diagnostic pathology serves to improve both diagnostic reliability and the prognosis of various malignant tumors. Unfortunately, flexible, user-friendly, reasonably priced and compatible morphometric systems are hardly available on the market. A modular Apple II PC-based system was therefore developed in-house. It records stereologic, planimetric and digital image analysis data and calculates secondary parameters. Detailed statistical analyses can be performed, after data transfer, on larger computers. A typical application of diagnostic morphometry is to determine whether, and with which probability a patient with an unclear histopathologic finding can be assigned to one or more groups of patients with known diseases and prognoses. To this end morphometric data of the patient under investigation are compared with other patient data stored in an expert system. This paper describes the concept of an expert system carried out on the Apple II PC system mentioned above and outlines the evaluation procedures. Invariant moments were used to describe nucleus textures. Results obtained from the cytological analysis of pleural effusions demonstrate that with this approach it is possible to differentiate between normal mesothelium, mesothelioma and metastases of adenocarcinomas.

Adenocarcinoma↗
PubMed1989

Digital image analysis in cytological diagnosis: a morphometric analysis on pleural mesotheliomas.

In the course of the last years digital image analysis has become increasingly important in the field of quantitative pathology. This may be due to the technical development of computers which have now reached a high user-friendly standard. In the present paper we present: (1) the development of a simple system for the measurement of digital image analysis; (2) the development of a general data structure applicable to various measurements and classification strategies; and (3) the analysis of the value of invariant moments (IM) as regional descriptors to distinguish mesothelial cells from mesothelioma cells in cytologic smears of pleural fluid. The results show that the invariant moments contain information concerning the geometric distribution of the grey values of the pixels as well as the staining intensity. The invariant moments present combination parameters and are therefore ideal morphometric parameters. With the invariant moments 7 out of 7 patients with mesotheliomas and 8 out of 11 control subjects could be assigned correctly in a nonparametric discriminant analysis procedure.

Cell Nucleus↗
PubMed1987

A semiautomatic image analyzing system based on an APPLE II or IIe personal computer.

A new semiautomatic image analyzing system based on an APPLE II or IIe personal computer is described. The configurations of the hardware and software are extensively explained. The possibilities of applying the system are demonstrated by different examples taken from various projects in biological research and clinical pathology. The system is designed to fulfil the following requirements: (1) stepwise realization as a unit-by-unit system according to individual needs and interests, (2) acquisition and calculation of morphometric parameters, (3) provision of solutions for the greatest possible number of given problems in clinical and experimental pathology, (4) direct connection of the system to host computers for on-line data transfer and evaluation, and (5) optimum cost-benefit ratio by manifold application possibilities for the individual hardware and software elements. The advantages of the unit-by-unit system with personal computers outweigh in many respects the disadvantages (for example, increased file handling and limited capacity) in comparison with the closed automatized image evaluation system, particularly with regard to costs, flexibility and compatibility. The system is being further developed in collaboration with Kontron Bildanalyse GmbH, Eching/Munich, FRG.

Animals↗
PubMed1983

Development of the acrosome and alignment, elongation and entrenchment of spermatids in procarbazine-treated rats.

Intraperitoneally administered procarbazine caused, among other features previously reported (Russell et al., 1983), specific defects in the acrosome of cap phase spermatids of the rat seminiferous epithelium. The effect of procarbazine was to fragment and eventually cause resorption of the acrosomes of a small number of steps 5--9 spermatids. Although the acrosome was lost, close union of the leaflets of the nuclear envelope underlying the acrosomal sac was maintained as was the marginal fossa and acrosomal zonule. Spermatids at steps 8 and 9 of development, which had lost their acrosomes, showed nuclei which were eccentric within the cell--a feature which normally occurs at these steps of spermiogenesis in acrosome intact cells. Even without an acrosomal sac, the plasma membrane of these cells (in stage VIII) became orientated to the region of the nuclear membrane which would have underlaid the acrosome. Although abundant, Sertoli ectoplasmic specialization did not become aligned with the spermatid head. The spermatid failed to become orientated within the seminiferous epithelium and failed to enter the crypts within the Sertoli cell as usually occurs during the elongation process. Thus, the presence of an acrosome is not likely related to the formation of an eccentric nucleus or the alignment of the surface of the nucleus which would normally underlay the acrosome with the cell's plasma membrane (internal alignment). The presence of an acrosome may be related to the alignment of the spermatid head with the ectoplasmic specialization, which in turn may influence the orientation and positioning of the late spermatids within the seminiferous epithelium (external alignment) and their position within recesses of the Sertoli cell. This study also suggests a role for the manchette in the process of elongation of the spermatid.

Acrosome↗
PubMed1983

Morphological pattern of response after administration of procarbazine: alteration of specific cell associations during the cycle of the seminiferous epithelium of the rat.

Procarbazine, an anti-cancer agent, administered intraperitoneally to adult, male rats induced a characteristic morphological pattern of response in the seminiferous epithelium. Seminiferous tubules of rats receiving 100 mg/kg procarbazine and higher dosages displayed spermatids which were less mature than those normally found within seminiferous tubules which show a particular cell association. Early spermatids in steps 1-7 of spermiogenesis appeared arrested in their development and were present in cell associations which had advanced normally. The most probable cause of this apparent germ cell arrest was a retardation of acrosomal development since procarbazine is known to affect RNA and consequently protein synthesis. Other features which indicated defective RNA synthesis were the presence of abnormal spermatid nucleoli and abnormally configured chromatoid bodies. This study demonstrates, in contrast to what is indicated by present dogma, that apparent and temporary germ cell arrest may occur under certain deleterious conditions. It also illustrates that particular cell types within a cell association may be out of synchrony with the remainder of the cells in a cell association.

Animals↗
PubMed1982

Histological changes during regression induced by retinoic acid in a transplantable rat chondrosarcoma.

Daily oral treatment with retinoic acid (100 mg/kg bodyweight) induced regression of a transplantable rat chondrosarcoma. In a previous biochemical investigation we have shown that the tissue breakdown is preceded by the loss of proteoglycan. The present study describes the histological changes induced by retinoic acid. A decrease in the intensity of metachromatic staining with toluidine blue was noted already after 1 day and the discoloration was almost complete after 4 days correlating with the loss of proteoglycan. Especially in the perichondrium there was a rapid proliferation of fibroblasts and monocytes. Osteoclast-like cells were missing, but tumor nodules were eroded and split up by penetrating perichondrium. After 4 days of treatment larger necrotic areas were found, initially in the center of tumor nodules only. In other areas the majority of tumorous chondroblasts survived. Tumor nodules appeared partly mesenchyma-like with some fibroblast-like cells suggesting a dedifferentiation of chondroblasts by retinoic acid. we believe that tumor regression induced by retinoic acid involved proteoglycan degradation by chondroblasts themselves and chondroclast-like activity of monocytes and fibroblasts.

Animals↗
PubMed1980

Electrocardiographic changes in rats during chronic treatment with antidepressant and neuroleptic drugs.

Five antidepressants, 3 phenothiazines and 5 butyrophenone neuroleptics were administered to rats orally at maximally tolerated doses for 22 weeks. The electrocardiogram (ECG) was recorded weekly. In animals treated with antidepressants quinidine-like changes of the atrioventricular and intraventricular conduction developed. There were also elevation of T-wave and right rotation of the electrical axis. Dibenzepine had the least effect on the ECG. In the group of phenothiazines chlorpromazine induced tachycardia and thioridazine widening of the QRS complex. Prothipendyl had no effect. ECG-changes induced by some of the butyrophenone derivatives were tachycardia and widening of the QRS-complex. In rats treated with protriptyline the ECG changes were correlated with drug concentrations in serum and myocardial tissue. The studies provided a quantitative assessment of the cardiac effects of clinically proven psychotropic drugs. They will be useful as a baseline for the preclinical evaluation of new derivatives.

Animals↗