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Biomedical subjects

P Pfitzer

Publications and source records attributed to P Pfitzer.

At least 55 records · Page 3Linked to original sources
PubMed1983

Ploidy in the hearts of elderly patients.

The DNA-ploidy of the left and right ventricular wall in 48 patients aged 80-98 years was investigated by scanning cytophotometry. The great variation in nuclear ploidy previously described in the heart muscle was shown to persist during the ninth decade. In addition, the percentage of nuclei with more than 2C DNA content in both ventricles correlated with the degree of coronary stenosis, and in the right ventricle with the presence and severity of pulmonary emphysema, and with the duration of digitalis therapy where this drug was given.

Aged↗
PubMed1983

Postnatal DNA-syntheses and mitoses in hearts of dwarf pigs.

Postnatal DNA synthesis and mitoses have been investigated in the heart muscle of 23 dwarf pigs by autoradiography and by light and electron microscopy. During the first weeks the average labelling indices of the myocardium decrease from 3.7 +/- 1.6% to 1.9 +/- 0.6%, while considerable individual variations are observed. The average mitotic indices decrease from 1.0 +/- 0.7% on the tenth to 0.2 +/- 0.1% on the 30th day. The number of two synchronous mitotic figures in the same cell increases from 7.5 to 32.5% in the first postnatal month and causes the mitotic development of nuclear rows. The period between 2 and 8 months after birth is characterized by low DNA synthesis at least in one of the investigated ventricular tissues.

Aging↗
PubMed1982

[Effects of long-term ventilation on the bronchial system. Bronchoscopic, cytologic and microbiological findings].

UNLABELLED: The effects of longterm ventilation were evaluated in 50 patients from a medical intensive care unit. The bronchial tract was investigated using repeated bronchoscopy and assessed by semiquantitative scoring. Prior to each endoscopy tracheal secretions were obtained for microbiological and cytological evaluation, in 20 patients histological analysis of the bronchial mucosa was done in addition. RESULTS: 1. Within 24-48 hours after initiation of respirator ventilation alterations of the bronchial mucosa occur. The extent progresses rapidly, however no further increase of progression is to be observed after ventilation of approximately 150-200 hours. 2. Endoscopic assessment of the severity of mucosal changes correlates well with cytological and histologic results. 3. In 34 patients microbial agents could be demonstrated. In 8 of them mucosal changes preceded demonstration of microbial organisms. The extent of mucosal changes is independent of category or count of pathogen. Endoscopic follow-up investigations of the bronchial tract affected by long-term ventilation serve both direct bronchial clearing and control of position of the intubation tube as well as assessment of mucosal alterations and control of treatment of bronchial infection.

Adolescent↗
PubMed1982

Flow cytometry of human testicular tissue.

Flow cytometry of testicular tissue from autopsies showed differences in the proportion of substained spermatozoa (1 CA), spermatids (1 CB), diploid 2C nuclei and premeiotic spermatozoa in the 4 C class. The evaluation of the histograms was performed with computer assistance. Healthy accident cases or those delivered in forensic medicine furnished the control values. Patients with hepatic cirrhosis showed a nearly complete loss of the haploid class, while cases with fatty degeneration of the liver demonstrated a reduction. Circulatory insufficiency in cases of acute shock resulted in an increase in the 4C values of meiotic prophase I and a decrease of spermatids. Spermatozoa were normal in these cases. After prolonged shock a nearly complete breakdown of spermatogenesis was observed. In cases of atherosclerosis an irregular degree of reduction was seen. Cancer patients showed a reduction of spermatogenesis in correlation to therapy.

Adult↗
PubMed1980

Amitosis: a historical misinterpretation?

"The problem of amitosis" (Bucher, 1971) has historical, theoretical, formal, and methodological aspects. Most cases of amitosis described during the past 125 years have proved to be misinterpretations of incomplete mitoses. Binucleate cells and occasionally dumbbell-shaped restitution nuclei are formed as the result of mitotic inhibitions, which increases with tissue differentiation. Until recently, binucleate cells in the myocardium have been interpreted as products of amitotic nuclear divisions, since mitoses are not found in human myocardium. However, mitoses are found in postnatal pig hearts fixed immediately after death. The mitotic index declines from 2.2% at day ten to 0.3% at day thirty during postnatal life. Delayed fixation yields degenerated prophase and telophase nuclei only. Thus the formation of binucleate myocardial cells and nuclear rows is the result of mitoses with impeded cellular divisions. To call these findings examples of amitosis is a misinterpretation.

Animals↗
PubMed1978

[Cell cultures as vitality test for preservation of kidneys by deep freezing (author's transl)].

Cytologic examinations of kidneys, which were frozen for preservation in a nitrogen atmosphere below 3 ata, show a considerable damage of the cells. This does not only occur by significant reduction in the amount of isolated cells, but also in the loss of the ability to form cell colonies. DNA measurements show, however, that after 3--4 days the DNA amounts in surviving cells are intact. In one of the cultures we even found DNA values, which stand for a DNA synthesis. Experiments with mechanical perfusion alone show that this procedure results in a severe damage of the cells, only about one-third of these cells being able to form colonies.

Animals↗
PubMed1978

[Contributions to the morphological basis of the cytology of the respiratory tract (author's transl)].

It is reported on 275 cases treated for bronchial carcinoma at the Surgical Departement of Düsseldorf University between 1970 and 1974. In all cases cytological as well as histological methods were used for diagnosis. These cases are complemented by 60 cases selected under cytological aspects from other sources. Localization by X-ray proved a central tumor in 11% and tumors in the different lobes in 89% of the cases. Tumors were more frequent in the upper lobes (54%) than in the lower lobes (30%), and more frequent in the right lung (58%) than in the left (42%). Cytological smears were positive or suspicious in 77% of the central carcinoma and in 60 and 56% in cases of roentgenologically peripheral localization. There is no difference found between tumors in the upper and lower lobes. Bronchial secretion renders less positive results for all histological types. This indicates a small area of origin for the cells investigated by this method. Metaplastic cell changes were observed in one third of all cases involving all histological types equally. Operation was possible in only 30% of the cytologically diagnosed cases in comparison to 52% of all cases. The 60 selected cases were composed of 48 primary and twelve secondary tumors. Probatory excision had been performed in 50%, 8% remaining negative even after repetition. 33% could only be verified by autopsy corresponding to 29% with sputa, bronchial aspirate and pleural effusion positive at the same time and therefore regarded as late stages. Negative results can be caused by fibrosis as well as obstruction, fibrosis not being a regular result of treatment with X rays. Differentiation of tumor types is possible in cytological smears. Sometimes differences in the same tumor are evident and occasionally the tumor type can be more distinct in the cytological preparations. Metastatic tumor cells are open to false classification. Tumor and tuberculosis were found in four of sixty cases. One false positive result was caused by cells ressembling cases of experimentally induced bronchiolization of alveoli by different noxa.

Bronchial Neoplasms↗
PubMed1977

Facultative polyploidy in endocrine tissues.

Adrenal tissue from 44 autopsies and 30 biopsies of thyroid gland were analyzed by flow--and scanning-cytophotometry. Most nuclei were diploid and the 4C fraction ranged from 1.9 to 6.1% according to the technique, but with no significant difference between controls and adenomas, hyperplasias, adenomatous goiters, or two carcinomas of the thyroid gland. The only significant increase of 4C fraction was found in normal adrenals of patients above 50 years of age (P less than 0,025). Similarly constant was the proportion of 8C nuclei which ranged from 0.5 to 1.3 per thousand. However, in one of 23 adenomatous goiters a total polyploidization was was observed. Comparable results in the literature show that the thyroid gland like the epithelium of seminal vesicles can facultatively become polyploidized, in contrast to the obligatory polyploid orgnas namely the liver and heart. This is not related to malignancy.

Adenocarcinoma↗
PubMed1977

Nuclear DNA of myocardial cells in the periphery of infarctions and scars.

In 20 hearts the enlargement of muscle fibers and the increase in nuclear DNA is studied in the periphery of fresh and healed infarctions. The data of attack is verified by ECG records in most cases, five had passed undiagnosed. Selective cytophotometry is performed by measuring the largest nucleus in each of 50 fields of comparable density. Since significant differences in polyploidization exist between the control regions of hearts of similar weight primarily regions of the same heart are compared. No differences are observed in five hearts with infarctions about one week old. After five to six months the enlargement of the fibers is significaant (P less than 0.0005) while the increase in polyploidy is still slight (P less than 0.15). In all cases with scars one to nine years old the enlargement of fibers is significant (P less than 0.0005) while the increase in DNA is significant in most of them (5 X P less than 0.0005, 3 X P less than 0.005, 2 X P less than 0.01). In a case with two lesions, one posterior five (P less than 0.0005) and one anterior seven years old (P less than 0.0005), there is still slight increase in polyploidy with age (P less than 0.1). In the five undiagnosed cases only one has no significant increase in DNA. There is no correlation found between the enlargement of fibers and the increase in polyploidy in this limited number of cases.

Adult↗
PubMed1977

Karyological and electron-microscopic studies in myocardial cells of primates after experimentally induced cardiac hypertrophy.

Precocious polyploidization in hypertrophic hearts of infants with congenital malformation can be reproduced banding the ascending aorta of young rhesus monkeys. Electron micrographs show hypoxic changes, signs of DNA, RNA, and protein synthesis as well as degenerative changes comparable to human hearts. Enforced polyploidization of cor pulmonale is found in rhesus exposed to coal quartz dust for 48 months. The pig heart, containing disturbed mitoses, serves as a model for incomplete mitoses. During evolution they became the rule for the myocardial cells of primates.

Animals↗
PubMed1976

[Analysis of DNA histograms by computer (author's transl)].

INTRODUCTION: Quantitative DNA cytophotometry, the study of morphology of chromosomes and cell kinetics are important approaches toward characterization of genetic information. Each approach has its own problems and limits. Difficulties with interpretation of DNA histograms arise from a lack of proper terminology, and from attempting to interpret them in terms of the existing terminologies for chromosomal analysis and cell kinetics. Aim of this research was to develop a computerized mathematical analysis of DNA histograms. MATERIALS AND METHODS: As a basis for the comparison of normal with those of tumor cell populations the DNA histograms of heart muscle cells were selected for the normal cell population from 14 normal hearts of adults, 16 hypertrophic hearts, 14 non-polyploidized hearts of children, and 14 hypertrophic hearts of children with congenital malformations. Normal diploid cell populations from 7 effusions were also included. The 24 populations of malignant cells consisted of primary tumors and metastatic effusions. DNA cytophotometry was performed on single nuclei in Feulgen stained preparations by means of the UMSP/XD 50 ZEISS. The approximation of the DNA histograms by linear combination of normal distributions was done according to spline-function and calculated by means of the IBM-375. RESULTS: The nuclear classes 2C, 4C, and 8C show no differences between the normal, left and right heart with respect to mean values (X), standard deviations (sx), variances (sX) and coefficients of variance (sx/X). However, coefficients of variance are smaller in hypertrophic (2.15 to 8.37%) than in normal hearts of adults (8.90 to 10.85%), and larger in hypertrophic heart of children (4.06 to 7.09%). The mean values of the DNA classes 2C, 4C, 8C, and 16C vary witin +/- 18.6% with a probability of 95.5%. Benign effusions contain only 2C and 4C nuclei with a variance of 4.00% and 8.75%, respectively. In DNA histograms of malignant cells, only one third has a first peak outside of 2C +/- 18.6%. In approximately one fifth of the histrograms the position of the second or third peaks deviates significantly from normal polyploid values. Since a large proportion of polyploid nuclei is limited to only a few normal tissues, pronounced polyploidy is suggestive of malignancy in all other tissues. If in the cases containing only two DNA classes, 2C and 4C, the populations are malignant, the proportion of 4C is more than 8% while in the corresponding benign populations the proportion of 4C atains only 2.97 +/- 2.5%. In some cases a few highly polyploidized nuclei not taken into a account by our computer program are suggestive of malignancy. In only one DNA histogram out of the 24 analysed, all of these criteria are negative. In six cases the computer analyses reveal two stemlines of tumor cells with corresponding polyploid values.

Adult↗