Search PubMed⌕ Search

Biomedical subjects

D J Ruiter

Publications and source records attributed to D J Ruiter.

At least 253 records · Page 14Linked to original sources
PubMed1982

Epidermal Langerhans cells in erythrokeratodermia variabilis. Histochemical and ultrastructural investigations before and after treatment with etretinate (RO 10-9359).

The distribution of epidermal Langerhans cells (LC) in erythrokeratodermia variabilis (EKV) was investigated using enzyme-histochemical (ATPase) and immunohistochemical (anti-T6 and anti-HLA-Dr) techniques. Biopsy specimens from lesional skin of five patients were examined before and 8 weeks after treatment with etretinate (RO 10-9359). In addition, electron microscopy studies were carried out in two of these cases. The number of ATPase-positive dendritic cells in lesional epidermis appeared to be remarkably reduced in comparison with normal skin from healthy subjects. After treatment, the number of ATPase-positive dentritic cells had increased but still remained below normal values. Similar but less striking results were found for anti-T6-stained specimens. The HLA-Dr antigen appeared to be unsuitable as a marker for comparative quantitative studies because of the highly variable expression of this antigen in the control specimens. Electron microscopy studies revealed LC in the basal and suprabasal layers of the lesional epidermis. Both before and after treatment, the LC exhibited a normal ultrastructure. In view of the clinical and histologic normalization of the skin lesions during treatment, these findings suggest that the decreased number of epidermal LC may be related to the abnormal keratinization that occurs in EKV.

Adenosine Triphosphatases↗
PubMed1982

Dendritic reticulum cell sarcoma? Four cases of a lymphoma probably derived from dendritic reticulum cells of the follicular compartment.

This paper describes the histological picture of four tumours of the follicular compartment of the lymph node, in which the proliferating cell appeared to be the dendritic reticulum cell (DRC). This assumption was based on the results of light microscopical, ultrastructural, immunological, and enzymehistochemical investigations. The tumour cells resembled DRC's closely in (1) the striking pattern of interdigitations and occasional tight junction-like contacts between the neoplastic cells on electron microscopical analysis; (2) presence of receptors for the activated third component of complement on the membrane of the cells; (3) absence of monoclonal immunoglobulins and T-cell antigen on the surface and of lysozyme, alpha 1-antitrypsin or alpha 1-antichymotrypsin in the cytoplasm of the neoplastic cells. Moreover, (4) the tumour cells showed moderate alpha-naphtyl acetate esterase, weak to absent acid phosphatase and (with one exception) strong 5-nucleotidase activity. Furthermore, (5) the neoplastic cells expressed Ia-like antigens on the surface in all four cases. The relation with follicle centre cell lymphomas, the differential diagnosis and clinical data are discussed.

Adult↗
PubMed1982

Major histocompatibility antigens and mononuclear inflammatory infiltrate in benign nevomelanocytic proliferations and malignant melanoma.

The presence of major histocompatibility antigens in malignant melanoma and benign nevomelanocytic lesions and the nature of associated mononuclear inflammatory cells were studied in situ by using monoclonal antibodies and an immunoperoxidase technique. HLA-A,B,C (HLA) and beta 2-microglobulin (beta 2m) were found on malignant melanocytes in primary cutaneous and metastatic melanomas. In contrast, HLA antigens were not identified on nevomelanocytes in benign hyperplasia or nevocellular nevi, although in some cases faint staining for beta 2m was present. The staining of nevomelanocytes for HLA and beta 2 was variable in cases of nevomelanocytic dysplasia. The degree of mononuclear cellular response correlated with the expression of HLA (or beta 2m) on nevomelanocytes. Most of the inflammatory cells were identified as T cells. The majority of T cells were of helper/inducer phenotype, whereas a lesser number were phenotypically suppressor/cytotoxic T cells. The findings suggest that expression of HLA may be involved in triggering or eliciting a cellular immune response against dysplastic or malignant nevomelanocytes.

Adult↗
PubMed1982

Sarcoidosis of the liver, complicated by bleeding oesophageal varices.

Case report of a 57-year-old woman with pulmonary and hepatic sarcoidosis. As a rare complication, portal hypertension developed and first became manifest as bleeding from oesophageal varices. A portocaval shunt was successfully performed and the patient remained in stable condition after a follow-up of two years.

Esophageal and Gastric Varices↗
PubMed1982

The implications of subjective recognition of malignant cells in aspirations for the grading of prostatic cancer using cell image analysis.

A pilot study of selective morphometry was performed in smear preparations from fine needle aspirates of six cytologically graded prostatic carcinomas. Given the instruction to select carcinoma cells with large nuclei for measurement, cytotechnologists and a cytopathologist differed in the selection of cells from grade III tumors. The cytotechnologists had discarded large bare atypical nuclei because they assumed that these were degenerated cells. Transmission electron microscopy, using an open-face embedding technique, demonstrated, however, that these cells were not degenerated but were poorly differentiated carcinoma cells that had lost their cytoplasm during smear preparation. It is obviously of great importance for the morphometric discrimination of grade I and grade III carcinomas that such bare atypical nuclei be included in the selections of cells to be measured. Our data indicate that the measurement of 20 selected cells per smear preparation is sufficient for accurate morphometric grading and that such measurements are reproducible.

Biopsy, Needle↗
PubMed1981

Secreting peritoneal mesothelioma. Report of a case with cytological, ultrastructural, morphometric and histological studies.

A 29 year old woman, living in an area with a high level of asbestos exposure, developed the clinical features of peritoneal mesothelioma. The quantitative cytological features differed from those of other mesotheliomas described in the literature in that the tumor cells had a large amount of vacuolated cytoplasm and an extremely low N/C ratio, resulting in a "benign" appearance. The ultrastructural study provided evidence for the production and accumulation of secretory products (mucolipids) by the tumor cells. Treatment with chemotherapy and radiation resulted in temporary remission, lasting for 20 months. However the patient then developed pulmonary involvement of the carcinomatosa a form and pleural tumors. The cytological pattern and the morphometric features of the metastatic floating malignant mesothelial cells in the pleural fluid closely resembled those of the primary peritoneal tumor. This case appears to be an example of secretory peritoneal mesothelioma with a bad prognosis, not withstanding the well-differentiated appearance of the tumor cells.

Adult↗
PubMed1981

Malignant lymphoma of true histiocytic origin: histiocytic sarcoma. A morphological, ultrastructural, immunological, cytochemical and clinical study of 10 cases.

Ten tumors of true histiocytic origin (Histiocytic Sarcoma) are presented. The tumor cells were identified as histiocytes by immunological, cytochemical and ultrastructural criteria (cytoplasmic lysozyme activity, presence of C3 and Fc gamma receptor, strong acid phosphatase and alpha-naphthyl acetate esterase activity, presence of lysosomes, absence of cell junctions and evidence of phagocytosis). The tumors identified in this way showed the following histological characteristics: diffuse proliferation of large tumor cells with ample cytoplasm, containing granular or occasionally diffuse diastase resistant PAS positive material, erythrophagocytosis, and haemosiderin pigment. The large or enormous nuclei were irregular, with occasional deep indentations, sharply defined nuclear membrane, coarse chromatin and conspicuous nucleoli. Despite the uniformity of these criteria differences in presence of alpha 1-antitrypsin, alpha 1-antichymotrypsin and 5 Nucleotidase activity and the number of lysosomes in the cytoplasm were found. The findings are suggestive of a spectrum of cytological in these Histiocytic Sarcomas. The clinical picture ranged from monolocalization in a lymphoid organ to that of a diffuse Malignant Histiocytosis. The relationship between good response to therapy and complete remission and the absence of alpha 1-antitrypsin and a high number of lysosomes is discussed.

Adult↗
PubMed1981

Chemodectoma (paraganglioma) of the larynx.

Two cases of chemodectoma of the larynx, 1 benign and 1 malignant, are reported. Initially both tumours caused diagnostic problems but the diagnosis could be confirmed by silver staining and electron microscopy. So far only 25 cases of laryngeal chemodectoma have been reported in the literature. Clinically, the diagnosis should be considered when a persistent, smooth, non-inflammatory intralaryngeal swelling, particularly with a reddish-blue colour, is encountered. A final histological diagnosis can only be made with additional histochemical techniques and electron microscopy.

Aged↗
PubMed1980

Diffuse cutaneous mastocytosis with multiple cutaneous mastocytomas. Report of a case with clinical, histopathological and ultrastructural aspects.

A patient with diffuse cutaneous mastocytosis, present since birth, developed several cutaneous mastocytomas without any symptoms after puberty. Although the histological picture of the tumours, showing nuclear atypia, mitotic figures and varying metachromasia of the granules, raises suspicion of systemic involvement, this has not appeared so far. The absence of symptoms could be due to the synthesis of an abnormal secretory product by the mast cells, which is supported by the absence of oedema and dilated blood vessels in the presence of extensive degranulation and by the unusual ultrastructural picture of the mast cell granules, i.e. little electron density with the almost complete absence of lamellar and crystalline structures.

Adult↗
PubMed1980

Metastatic skin calcification. A rare phenomenon in dialysis patients.

Calcification of the skin could not be demonstrated in 60 skin biopsy specimens, selectively obtained from 30 chronic hemodialysis patients; 21 of these patients had metastatic calcification at other sites. These results support the proposed rarity of metastatic skin calcification in patients with chronic renal failure. The cause of this phenomenon is not precisely known.

Adolescent↗
PubMed1979

Legionnaires' disease: case report with special emphasis on electron microscopy and potential risk of infection at autopsy.

A case of Legionnaires' disease (LD) is presented in which the diagnosis was made initially by EM and later confirmed by specific immunofluorescence of formalin-fixed, paraffin-embedded lung tissue. The possibility of an infection with Legionella pneumophila during autopsy is suggested by the fact that the pathologist who performed the post-mortem examination developed signs and symptoms of an upper respiratory tract infection 2 weeks afterwards. Approximately 4 weeks after the onset of his illness a significant antibody titre against L. pneumophila was found in his serum, whereas 6 months later the antibody titre was insignificant.

Aged↗
PubMed1977

Aneurysmal bone cyst and telangiectatic osteosarcoma. A histopathological and morphometric study.

In a series of 105 cases of aneurysmal bone cyst, 18 showed an unusually high level of mitotic activity and/or increased nuclear pleomorphism which complicated the differential diagnosis with respect to telangiectatic osteosarcoma. An attempt was made to use semi-automatized morphometric and histophotometric techniques to establish objective morphological differences between these unusual cases of aneurysmal bone cyst and 16 cases of telangiectatic osteosarcoma. Three cases (two of aneurysmal bone cyst and one of telangiectatic osteosarcoma) proved unsuitable for analysis. In 24 of the remaining 31 cases (77%) a computerized discriminant analysis permitted correct discreimination with a high degree of certainty on the basis of quantitative nuclear characteristics determined in paraffin sections. In the other 7 cases the diagnosis was less certain (3), doubtful (2) or erroneous (2). The relevant nuclear characteristics were (in ascending sequence of discrimination): the largest nuclear surface area, the mitotic index, and the percentage of nuclear sections exceeding an arbitrarily chosen limit of 60 micron2. The criterion of nuclear size for discrimination between these benign and malignant lesions could be applied for two reasons: firstly, because a group of extremely large nuclei occur in malignant cases, and secondly, because the average nuclear size is larger in malignant than in benign lesions. The extremely large nuclei occur as only a small percentage of the total nuclear population. The other variables investigated, i.e., cellularity and nuclear contour ratio, did not contribute greatly to the differentiation. In 11 cases, the average nuclear Feulgen extinction was estimated as an additional variable.

Adolescent↗
PubMed1977

Correlation of scintigraphy with short interval autopsy in malignant focal liver disease: a study of 59 cases.

The accuracy of scintigraphy in focal liver disease was evaluated by comparing the scintigraphic and autopsy findings in 59 patients. The interval between scintigraphy and autopsy was not more than a few weeks. The overall agreement rate was 49 in 59 (83%), with four out of 26 (15%) false positive and six out of 33 (18%) false negative reports. Defects smaller than 2 1/2 cm were the principal source of false negative reports. The accuracy of interpretation in cases with liver weights up to 2000 g was significantly (P less than 0.025) lower than for higher weights. Detection of a single focal lesion by scintigraphy was found to be unreliable (only two out of 13 correct). Estimation of spleen weights by scintigraphy was disappointing. Liver weight estimates were somewhat more satisfactory.

Adult↗
PubMed1977

Aneurysmal bone cysts: a clinicopathological study of 105 cases.

A clinicopathological review of 105 cases of aneurysmal bone cyst is reported. Age and sex distribution and localization were in agreement with two previously reported large series. Recurrence occurred in 30.5% of all the cases and in 34.2% of those treated by curettage. Proved incompleteness of surgical removal was an important factor in recurrence (12 out of 17 cases or 70.6%). The recurrence rate was significantly (P2 less than 0.01) higher in cases with a mitotic index of seven or more per 50 fields (X 750) than in those with a lower mitotic index. In relation to the recurrence rate, no statistically significant differences were found between the age groups less than or equal to 15 and greater than 15 years, between the combination age and lesion size, or between four localization groups. The cyst wall and the septa consist of a superficial layer of cellular fibroblastic and histiocytic tissue in which multinuclear giant cells are present, covering a deeper situated zone of less cellular fibrous tissue. This typical layered architecture was found at one or more places in 93 (88.6%) out of 105 cases. However, layered architecture may also be found in cases of teleangiectatic osteosarcoma. It is suggested that the group with a high risk of recurrence be treated more radically, i.e., with cryosurgery.

Adolescent↗
PubMed1975

Fibrinolytic activity in aneurysmal bone cysts.

Euglobulin fibrinolytic activity of cyst fluid from six patients with aneurysmal bone cysys was considerably higher than that of arterial and venous blood of the corresponding patients. The high fibrinolytic activity was associated with a very low concentration of fibrinogen and a low concentration of plasminogen. Correspondingly, a high plasminogen activator activity was found in cyst tissue related to endothelial lining. It is suggested that fibrinolysis is an important factor in the maintenance and expansion of the aneurysmal bone cyst.

Adolescent↗