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P Rother

Publications and source records attributed to P Rother.

At least 37 records · Page 2Linked to original sources
PubMed1984

[Quantitative and qualitative aspects of the representation of aging curves for the histological composition of the human submandibular gland by empirical regression].

A discussion of the possibilities is given of parametric and of nonparametric description of measured aging processes. As examples serve the counted volume portions of different histological structures in the human submandibular gland. As best suited approach the nonparametric evaluation of data by empirical regression is recommended. It is studied which qualitative changes are shown by the empirical regression curves if the sample size will be modified. For this the original sample size of 42 measured values is reduced in 2 steps to 35 and 29 values by removing at random firstly 7 and secondly additional 6 values. The tendencies in the aging courses represented by empirical regression curves will hardly altered by these reductions whereas a nonrandom elimination of outstanding points yields to marked changes in the calculated empirical regression curves. The influence of different local sample variances and densities of the measured points on the shape of the aging curves is stressed.

Adolescent↗
PubMed1984

[Dynamics of the distribution of variables in morphology].

This paper discusses examples of exponentially distributed, Poisson-distributed, and binomially distributed random variables from morphology and describes secular and historical processes as well as phenomena of aging as factors of the dynamics of such distributions, the major focus being on tests of morphometric variables for the existence of normal distributions. In those cases where hypotheses of the existence of particular distributions of random morphometric variables are established it is necessary that consideration be given to metrological and stereological factors pertaining to the process of measuring and the geometry of the structures being measured, respectively. Karyometric results are used to demonstrate the splitting of a single statistical population into several populations as a result of the process of aging of the human organism.

Aged↗
PubMed1983

[Application of three-dimensional contingency tables to histology].

With examples of the morphology of parathyroid glands the application of threedimensional contingency tables to histology is shown. On 138 human parathyroid glands the following qualitative characteristics were established out of among other points: sex, position, predominating type of structure and predominating cells. By analysis of threedimensional contingency tables it has been investigated, if, taking into consideration the position, the sex, or taking into consideration the sex, the position influence the type of structure and the predominating cells of the organs. In both cases it was found a total independence as well as an uneven distribution of cells and types of structure respectively.

Female↗
PubMed1983

[Dependence of the number of chromocenters on age and size of cell nucleus].

On Feulgen-stained slides of adult rats' liver we determined the biggest and the smallest diameters each of 200 nuclei of hepatocytes. By using the table of Marzotko we got the real volume of the nuclei. Besides the volume we found the number of chromocentres in the nuclei. We also investigated the Feulgen-stained nuclei of mucous epithelium of buccal cavity of an adult man. The purpose of this study is to determine the number of chromocentres (1) in relation to the size of the nucleus and (2) in relation to the age of the cell. According to our investigation we found out that there is (1) a positive correlation between the number of chromocentres and the size of the nucleus and (2) a negative correlation between the number of chromocentres and the age of the cell. Both are statistically significant.

Adult↗
PubMed1983

[Morphometrically definable aging velocities of cells and tissues].

We determined aging changes of the nucleus-cytoplasm-relation in the epithel of the human epiglottis and intestine of rats. The results were compared with data about the proliferation of connective tissue and the decrease of muscle cells in the wall of the intestine and in the ciliary muscle. We adapted exponential functions to the measured results. For comparing the several equations and the derivable aging velocities, the nucleus-cytoplasm-relation must be transformed into nucleus volume rate of the total cell volume. Similarities in the decrease of the aging speed in the course of life and in the value of the exponent of the aging function by W. Beier (approximately 0,03) were demonstrated.

Aging↗
PubMed1983

[Application of terms of probability theory in embryology and teratology].

The aim of the paper was to show that accurate morphological statements can be made with the help of simple concepts of the theory of probability. Binomial distribution was used to find out whether the number of male and female births in large families was random or whether a particular disposition to boys/girls was to be assumed. It was found that the relation was random as a rule. A second question was that of the connection between a number of simultaneous variations and deformities. After the injection of trypan blue, combined deformities were studies in rats and found to be independent of each other, i.e. all had been directly caused by trypan blue.

Abnormalities, Severe Teratoid↗
PubMed1982

[Wilhelm His Senior--the life and work of the important Leipzig morphologist].

The paper describes the life, work and personality of Wilhelm His, the prominent morphologist who taught at Leipzig University between 1872 and 1904. It therefore contains details from the history of medicine in the second half of the last century. Mention is made of the character features which made the work of Wilhelm His so successful and brought him worldwide recognition--a ceaseless thirst for knowledge, enormous diligence and an unwavering love of truth.

Anatomy↗
PubMed1982

[Morphometric studies of the aging of human submaxillary glands (author's transl)].

Morphometric examinations were made on hematoxylin-stained paraffin sections of 43 human submaxillary glands, in order to determine and describe histological changes of this organ during the aging thereof. The number of fat cells per unit area increases in the first decades, whereas that of the striated ducts decreases. Obviously, striated ducts differentiate earlier than serous acini, with the former thus being less subject to involution with aging than the latter. In old age, the nuclei of the epithelial cells of serous acini and striated ducts are characterized by the formation of certain classes of size, of which the association with polyploidization is, however, questionable. In a 44-year-old male, differences in the size of nuclei between different striated ducts of one section, which were due perhaps to functional peculiarities, indicated the existence of inactive and active glandular regions. The volume density of serous acini decreases continuously in the course of life, while that of the striated ducts decreases in the first decennia only. On the other hand, there was observed a continuous increase in the volume density of fat cells in the entire course of life and an increase of the volume density of connective tissue in the second half of life. The mucous fractions were observed to increase up through the fifth decade of life, after which they were seen to decrease continuously.

Adolescent↗
PubMed1981

[Speed of and sex differences in the aging process in human tissue].

By means of the point counting method we determined the decrease of musculature and the increase of the connective tissue in the ageing ciliary muscle of the human eye and in the tunica muscularis of the small intestine as well as the increase of fatty tissue in human parathyroid glands during life. The paper describes the changes found by adaptation of exponential functions to the series of marks and reveals the implications resulting concerning the speed of the histological biomorphosis in the individual part of life as well as on their theoretical final stage. The speed of ageing permanently decreases from birth to death and aims at zero. There are only small differences between the observed parts of muscles and connective tissue, respectively, of very old people and the calculated values for "immensely" old people. Human parathyroid glands age markedly different to sex. The sexual divergence of the biomorphosis may be among others be morphometrically demonstrated on the basis of the increase of the interstitial fatty tissue.

Adipose Tissue↗
PubMed1981

[On the strategy of measuring in gerontology (author's transl)].

By the point counting method and empirical regression we investigated the aging changes in volume densities of histological structures in 43 human thyroid glands and in 42 human submandibular glands. Especially we wanted to show, how the change of the most important errors influences the shape of our aging curves. We had to take into consideration the statistical error, the error caused by the structural heterogenity, and the error caused by the interindividual variability. It was shown, that an increase of the exactness of measuring as well as a consideration of the structural heterogenity in the organs do not change the course of aging curves and 42 or 43 cases were sufficient for our investigations.

Adolescent↗
PubMed1980

[Determination of body height from fragments of the femur].

Presenting a major problem in connection with reconstructing the height of body from the dimensions of long or pipe bones are the circumstances under which damage is caused thereto in mass accidents such as, for example, plane crashes. Such accidents often result in long bones being fractured completely, so that it is not possible for them to be directly used for reconstructing the height of body. In such cases, use can be made of the methods described by Steel (1970) who determined segments for such long bones as the femur, tibia, and humerus and also set up formulas by use of linear regression analyses, which enable the lengths of single fragments of bones to be used for estimating the overall length of bones which can then be substituted into equations for reconstructing the height of body. The procedure has been verified statistically, and suitable formulas have been established for the femur, which is the bone that lends itself particularly well to estimations of the height of body. When using these formulas, the residual variance is generally as great as 10 cm. Accordingly, it appears inappropriate for public medicolegal officers to calculate a height of body which is beset by a range of variation that is as great as this. Therefore, the 2nd part of this paper presents a possible way of determining the stature of a human body from individual segments of the femur. The limits of these size groups have been determined for data to be recorded in identity cards and other personal documents. The method is based upon the calculation of conditional probability distributions for given lengths of segments.

Adult↗
PubMed1980

[Classes of nuclear size of human hepatocytes in aging].

The objective of these studies was to follow the development in human liver parenchyma of the size classes of nuclei and determine the variations with age in the volumes and numbers of individual classes. A total of 400 parenchymal liver cell nuclei were measured on each one of 8 micron thick sections of 10 livers obtained from subjects of all age groups. For this, we used the Pictoval type of micro-projection apparatus (VEB Carl Zeiss Jena) at a magnification of 3000 times. The largest and smallest diameters of nuclear sections were determined, and the volumes in micron3 were ascertained using a table published by Marzotko (1966). The decomposition of mixed distributions was by the graphic method of Daeves and Beckel (1958). The results obtained can be summarized as follows: 1. Whereas the nuclei in a seven-year-old boy contained the diploid or normal double complement of chromosomes, the proportion of this "regular class" was seen to drop to 70 percent in old age. 2. The proportion of the tetraploid size class was observed to increase to 20 percent. 3. Hypertetraploid nuclei were clearly seen to increase in proportion (to about 10 percent) even in old age. 4. Diploid nuclei increased in size up to the time of life between youth and old age. There was observed real nuclear growth. In old age, they are subject to shrinkage. 5. Tetraploid nuclei also seem to grow smaller in old age. 6. In the discussion an attempt is made to explain the process of formation of nuclear size classes and show the functional importance of polyploidization of parenchymal liver cell nuclei. The latter seems to be a quantitative increase of the genetic possibilities.

Adolescent↗
PubMed1980

[The suitability of the graphic decomposition methods of Daeves and Beckel for mixed distributions in nuclear variation statistics].

The object of these studies was to determine the value of the graphic method of DAEVES and BECKEL (1958) for decomposition of mixed distributions in karyometry and to compare this method with a numerical one, published by HEROLD (1971). The former is as good as the latter, the only disadvantage of the graphic method is the loss of time by reason of the fact that employment of computers is not possible.

Aged↗
PubMed1979

[Histometric volume determination in aging human thyroid glands and possible errors of this method].

We made histometric volume analyses of hematoxylin and eosin stained paraffin sections of 43 human thyroid lobes by means of the electric integrating apparatus Eltinor 4 A (Optische Werke Rathenow). We investigated ageing changes of the relative amounts of epithel, colloid and connective tissue in the total volume. The volume density of colloid rises up to the 3rd decade, thereafter it shows a small decrease. On the contrary, the amount of epithelial cells decreases until the 3rd decade. The data concerning connective tissue exhibit an increasing trend up to senility. During such measurements errors appear, which are called, among others, total error, systematic and statistic error. We estimated these errors and demonstrated possibilities of their diminution.

Adolescent↗
PubMed1978

[Investigations on the aging processes of the humerus by means of histomorphometry, regression and factor analysis (author's transl)].

Histomorphometric measurements were made on bone sections prepared from osseous material removed from the diaphysial center of 70 macerated humeri obtained from persons in their third to ninth decades of life. The diameters of osteons and Haversian canals, the densities of Haversian and Volkmann's canals and osteocytes, and the proportions by volume of special and interstitial lamellae were determined. The parameters were checked for age dependence and subjected, together with previously determined macroscopic dimensions of the same left humeri, to regression analyses. Influencing variables entering into the most suitable formula for age determination include the cross-sectional area of the medullary space in the diaphysial center as well as the smallest diameters of osteons and Haversian canals. Factor analysis of the complex structure of characteristics yielded 4 factors, namely, the age factor, size factor, structural factor, and nutritional factor. Also discussed are the processes of internal transformation of adult bones.

Adult↗
PubMed1978

[The aging changes of biological variability (author's transl)].

1. Examples are given to justify the concept that biological variability is dependent on age. 2. It appears possible that the variability of fundamental parameters of those with a strong genetic fixation increases toward the middle of the life span and decreases again in the senium. 3. The variability of most variables increases with age. The more complex the variables, the greater the increase. 4. Originally unitary statistical populations may split up into several populations in the course of life. These will then require separate statistical treatment. 5. Our considerations seem to have some significance for the economical planning of tests and the selection of test persons.

Adaptation, Biological↗
PubMed1977

[The determination of age and sex from measure of the humerus (author's transl)].

On a total of seventy left humeri of persons in their third to ninth decades of life thirty different bone dimensions were determined macroscoically and checked for age dependence. Strong dependence on age was shown only by the weight and volume of the humerus as well as by the areal and thickness dimensins of the center of the shaft. These were used to set up multidimensional linear regression functions by which it is possible for the age of persons past thirty to be estimated with defined accuracy. Also calculated were discriminant functions which allow the sex of a person to be identified to be determined from three dimensions of the left humeral head, and these are the size of the caput at the cartilage-to-bone interface, the transverse and vertical diameters of the caput humeri or head of the humerus. Of the 49 cases studied only three were found to be in the region of overlap of the dimensions used for calculation. Consequently, the formula would not allow unknown humeri or skeletons, respectively, to be identified as belonging to either male or female persons in 6 percent of the cases only. The results of additional examinations made of 198 right humeri were less accurate and showed a decrease of the sexual dimorphism of bone with age.

Adolescent↗