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Biomedical subjects

G Steinmann

Publications and source records attributed to G Steinmann.

31 records · Page 2Linked to original sources
PubMed1982

Morphologic findings in lymph nodes after occlusion of their efferent lymphatic vessels and veins.

Cervical lymph nodes of rabbits were congested for 24 hours, 7 days, and 14 days by occlusion of the nodal veins, efferent lymphatics, or both. The lymph nodes were examined by histologic and morphometric methods, and the results were compared with findings in control nodes. The present study demonstrated that the vascular sinus transformation (VST), observed first in human lymph nodes, is reproducible experimentally. Complete occlusion of both the veins and lymphatics led to a marked increase in volume of the nodes and often to total necrosis of their parenchyma. Incomplete occlusion of the veins combined with complete occlusion of the lymphatics or complete occlusion of the lymphatics alone resulted in VST as early as 7 days after the operation. In the first stage of VST, proliferation of the subendothelial tissue accompanied by proliferation of blood capillaries was noted. The proliferation started from the capsular side of the marginal sinus and from the trabecular side of the intermediate sinuses. Subsequently, the sinuses transformed into a framework of channels resembling blood capillaries. Without occlusion of the efferent lymphatics, VST did not develop. Complete or incomplete occlusion of the veins combined with complete occlusion of the lymphatics resulted in a pronounced thickening of the capsule, sclerosis of the medullary sinuses, depletion of lymphocytes in the nodal parenchyma, and cavernous dilation of the medullary sinuses. After occlusion of the lymphatics alone these changes were less extensive. Occlusion of veins alone caused only moderate thickening of the capsule and slight sclerosis of nodal parenchyma, but no VST. Total necrosis of the parenchyma occurred only after combined complete occlusion of nodal veins and lymphatics.

Animals↗
PubMed1981

T-cell growth factor (interleukin 2) and terminal transferase activity in human leukemias and lymphoblastic cell lines.

Mononuclear blood cells from patients with different types of leukemia, and from controls as well as cells from established lymphoblastic cell lines were analyzed with respect to terminal transferase (TdT) activity and T-cell growth factor (TCGF; Interleukin 2, IL-2), to determine the significance of TCGF production and response as functional markers for human leukemias. The data obtained so far suggest that the aberrant proliferation and lack of maturation observed in these leukemias may be associated with or be the result of a break-down in cellular-mediated control of proliferation.

Acute Disease↗
PubMed1981

T- and B-cell responses in patients with malignant pleural effusions.

Lymphocytes of lymphocyte-rich pleural effusions and venous blood from 16 cancer patients, 7 patients with benign pleural effusions and blood from 23 normal blood donors, were examined for cytological features, rosette-forming capacity, immunofluorescent staining, and PHA-stimulated DNA synthesis. Total protein and immunoglobulin levels were also determined. Metastatic effusions revealed approximately 40% higher content of immunoglobulins G, A and M (P less than 0.002) as well as of total protein (P less than 0.005) than non-metastatic pleural effusions. However, the serum of the non-cancer patients contained approximately 50% higher level of Ig than in cancer patients (P less than 0.001). Whilst there was no significant difference in the relative T- or B-cell contents of pleural effusions between cancer and non-cancer patients (P greater than 0.05) spontaneous proliferation of lymphocytes was significantly increased (P greater than 0.01), which led to a lower PHA-stimulated transformation index in pleural effusions from cancer patients than in all other lymphocyte sources examined (P less than 0.001).

Adult↗
PubMed1981

Ultrastructural demonstration of terminal deoxynucleotidyl transferase (TdT).

Using an electronmicroscopic peroxidase-antiperoxidase technique in combination with a three-step fixation procedure according to Willingham, the ultrastructural site of terminal deoxynucleotidyl transferase (TdT) could be shown in cells of a human lymphoblastic leukemia cell line (MOLT 4). TdT appeared in the cytoplasm of the cells associated with large membrane bound granules from 150 to 600 nm in diameter usually arranged in aggregates. TdT-positive spaces were completely segregated form the rest of the cytoplasm and seemed to be interconnected by a tubular system. No TdT was detected in the nuclei.

Cell Compartmentation↗
PubMed1980

Factors in the cytological diagnosis of alveolar cell carcinoma.

Cytologic specimens of 23 patients suffering from histologically confirmed alveolar cell carcinoma (bronchiolo-alveolar carcinoma) were examined with respect to 47 objective and subjective criteria by two independent cytologists. The following characteristics were found: typical clustering of tumor cells (concretion = tightly packed cells, often finger-like packing or rosette-formation), hyperchromasia of the nucleus, size of tumor cells like or larger than alveolar macrophages, narrow ranges of nucleus-cytoplasm ratios (mean: 0.675; SD: 0.100) despite polymorphism of tumor cells, folding of the nuclear membrane, and signs of phagocytic activity (vacuolation, excentric position of the nucleus, erythrophagocytosis). A factor analysis of the results of examinations revealed six underlying factors of diagnosis. These factors are considered to be especially important for the validity of the diagnosis of a alveolar cell carcinoma and the occurrence of misinterpretations: yield of tumor cells in the specimen, type of clustering of the tumor cells degree of preservation, qualitative attributes of the nucleus, qualitative attributes of the cytoplasm, and quantitative measurements of the size of tumor cells.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMedDate not supplied

[Demonstration of terminal deoxynucleotidyl transferase in histological sections].

Terminal deoxynucleotidyl transferase (TdT) is a unique DNA-polymerase which is restricted to a few organs (thymus, bone marrow and blood). Therefore, the enzyme is suited for the role of a tumor marker in all other organs. The immunohistological demonstration, hitherto, was mainly hampered by the lack of potent and specific antibodies and by the readiness of the enzyme to diffuse. Now, these problems are solved. The immunohistological demonstration of TdT can be used to classify acute leukemias and lymphoblastic non-Hodgkin-lymphomas of children and to early recognize relapse situations.

Acute Disease↗
PubMedDate not supplied

Effect of methods of sample taking on the cytologic diagnosis of lung tumors.

By the evaluation of unselected cytologic specimens taken by different methods, the possible effect of sampling on the cytologic diagnosis was analyzed. A statistically significant tendency was established for certain tumors to be better diagnosed by certain methods of sampling. In order of the increasing radicality of the method, the following significant coincidences were found and discussed: Sputum for the diagnosis of bronchialalveolar cell carcinoma and epidermoid carcinoma (cornified cells); Bronchial washing for oatcell (undifferentiated) carcinoma and epidermoid carcinoma (moderately cornified cells); Bronchial brushing for epidermoid carcinoma (not cornified cells) and large cell (undifferentiated) carcinoma; Transthoracal needle aspiration for polymorphic carcinoma and metastasis; and Pleural effusion for the diagnosis of metastasis, bronchogenic adenocarcinoma and mesothelioma. If the clinical features indicate a certain tumor type, the data give evidence that it is advantageous to adjust the method of sample taking to the expected tumor type as far as possible. In the case of necessary re-examinations, transthoracic needle aspiration and bronchial brushing should especially be used, in addition to the self-evident examination of material produced spontaneously, i.e., sputum and pleural effusion, because of the relatively high expected value of these methods for positive diagnoses in re-examinations.

Biopsy, Needle↗