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Biomedical subjects

D Thorning

Publications and source records attributed to D Thorning.

36 records · Page 2Linked to original sources
PubMed1984

Liposarcomas. A histogenetic approach to the classification of adipose tissue neoplasms.

A series of atypical lipomas, well-differentiated/dedifferentiated liposarcomas, and myxoid/round cell liposarcomas were examined by light and electron microscopy in order to understand better the marked variation in histologic growth patterns exhibited by adipose tissue neoplasms. We found that they were composed of a mixture of adipocytes and nonfat-storing mesenchymal cells or were predominantly made up of only one of these cell types. From these and other published observations, we feel that 1) myxoid/round cell liposarcomas are composed of adipocytes; 2) spindle cell lipomas, atypical lipomas, and well-differentiated liposarcomas are composed of a mixture of the two cell types; and 3) the dedifferentiated regions of well-differentiated liposarcomas are composed of nonfat-storing mesenchymal cells. The basic structural differences of the two cell types and the quantitative variations when they occur in mixtures seem to account for the marked variations in neoplastic growth patterns.

Adipose Tissue↗
PubMed1982

Donor origin of the in vitro haematopoietic microenvironment after marrow transplantation in man.

The method for long-term culture of marrow cells in vitro as described by Dexter has recently been successfully applied to human marrow and is dependent on the development of an adherent stromal cell layer consisting of cells described as "endothelial-like cells, fat cells, and macrophages". The present study was designed to determine the origin and composition of the stromal cells forming the in vitro 'microenvironment' and maintaining haematopoiesis in long-term cultures grown from marrows of 14 patients who received marrow transplants from HLA identical siblings of the opposite sex. The presence of a Y chromosome was used as a marker to establish the donor or recipient origin of the cells. We found that the stromal cells became progressively donor in origin with time after transplantation and some reacted with antibody directed against factor VIII-associated antigen. In addition, donor-derived in vitro stromal cells synthesized both interstitial and basal lamina collagen types, indicating that the in vitro microenvironment is transplantable and composed in part of endothelial-like cells.

Adipose Tissue↗
PubMed1982

Histogenetic classification of lung carcinomas. small cell carcinomas studied by light and electron microscopy.

Forty-six small cell carcinomas of the lung identified by light microscopy were also studied by electron microscopy in an attempt to subclassify them histogenetically. Thirty were subclassifiable into neuroendocrine secretory, mucus secretory, or epidermoid categories on the basis of their differentiated structural features; 16 were too poorly differentiated to assign to any specific cell type and were designated null. In addition to histogenetic separation, electron microscopy revealed a spectrum of average cell differentiation within each subclass except null. The widest spectrum occurred in the most frequent subclass, the neuroendocrine group. This study clearly demonstrated that the light microscopic diagnosis of small cell carcinoma does not identify a morphologically homogeneous process. Whether histogenetic separation and/or some assessment of the relative degree of differentiation have any consistent clinical value remains to be shown; however, combined light and electron microscopy should improve the precision of the initial diagnosis over that of light microscopy alone.

Carcinoid Tumor↗
PubMed1981

Acquired trisomy 12 and absent Y chromosome in a patients with acute undifferentiated leukaemia.

A 60-year-old man developed pancytopenia and then acute leukaemia. The neoplastic cells in marrow were undifferentiated by electron microscopy and by immunological and cytochemical markers. The only other cells present in marrow were lymphocytes, plasma cells, macrophages and non-haematopoietic elements. Prior to chemotherapy, cytogenetic analysis of marrow cells showed two karyotypically distinct cell populations, one with 45,X,--Y and the other with a 46,X,--Y,+12 karyotype. All marrow cells stimulated by protein-A from staphylococcus aureus were 46,X,--Y,+12. Phytohaemagglutinin-stimulated cells were normal, 46,XY. These findings suggest strongly that most of the undifferentiated leukaemic cells were missing the Y chromosome. A subpopulation of these leukaemic cells also had trisomy 12. These observations and previously published findings suggest that trisomy 12 occurs non-randomly in haematological disorders, and in particular, may be associated with B-lymphoid malignancy.

Bone Marrow↗
PubMed1981

Spindle-cell lipoma. A clinical, light- and electron-microscopical study.

Five spindle-cell lipomas, all in male patients, were examined by light and electron microscopy. Four were located in the subcutaneous tissues of the upper back or posterior neck and one behind the left ear. They exhibited a spectrum of histological growth patterns. Electron microscopy demonstrated two distinct populations of tumor cells; one, a spindled non-fat-storing mesenchymal cell and the other a mature lipocyte. It is hypothesized that the spindled cells are analogous to the stellate mesenchymal cell of the primitive fat lobule.

Aged↗
PubMed1980

Peripheral neuroepithelioma: a light and electron microscopic study.

A primitive neuroectodermal tumor of peripheral nerve origin was examined by light and electron microscopy. The lesion arose in association with the S1 nerve root of the lumbosacral plexus in a 22-year-old female. Following a surgical biopsy, the patient received systemic chemotherapy; however, approximately one-and-a-half years later, she suffered a clinical relapse with locally recurrent tumor. An excisional biopsy was performed, and pathologic examination revealed progressive neuroblastic differentiation. The ultrastructural features of neoplastic Homer-Wright rosettes will be illustrated, and the non-specificity of cytoplasmic glycogen in the evaluation of "small round cell neoplasms" will be emphasized.

Adult↗
PubMed1980

Anthracycline cardiotoxicity: clinical and pathologic outcomes assessed by radionuclide ejection fraction.

A clinical syndrome of severe cardiomyopathy often accompanies administration of high doses of anthracycline agents. We studied 36 patients serially with radionuclide angiography. At three weeks following drug administration, 8 of 36 patients showed depression of ejection fraction (EF). All had received at least 280 mg/m2 of the drug and 7 had received more than 380 mg/M2. Definite clinical syndromes of congestive cardiomyopathy developed only in patients showing EF depression and in some patients, EF depression developed without signs of congestive heart failure. Ejection fraction studies at 5 minutes, 1 hour, 4 hours, 24 hours, 72 hours, and one week following drug administration showed no changes when compared to immediate preg-drug EF. Seven patients who died during the study underwent histologic examination. Only the single patient with a depressed EF showed histologic evidence of athracycline cardiotoxicity, although all but 1 of these patients had received at least 400 mg/M2. We conclude that serial radionuclide EF just prior to anthracycline administration is a potentially useful predictor of cardiac toxicity, and that EF depression and/or preservation of a normal EF should be weighed in the decision for administering a drug of this type at high dosage levels.

Antibiotics, Antineoplastic↗
PubMed1980

Liposarcoma metastatic to bone marrow presenting as myelophthisic anemia: a case report.

A case report of liposarcoma occurring in a man with probable hereditary multiple lipomata and metastasizing to bone marrow is presented. The neoplasm was studied by light and electron microscopy. The first evidence for metastatic disease was myelophthisic anemia. This unusual clinical occurrence is discussed briefly in conjunction with other neoplasms causing myelophthisis.

Anemia, Myelophthisic↗
PubMed1980

Effects of dietary acetate and bicarbonate on experimental atherosclerosis in rabbits.

Chronic hemodialysis, using acetate-containing dialysate, may accelerate the development of atherosclerosis in uremic patients. To assess the effect of acetate on plasma lipid levels and development of atherosclerosis, rabbits and rats were fed cholesterol-free semipurified atherogenic, Zn++-supplemented diets containing either 10% sodium acetate or sodium bicarbonate. Rabbit plasma cholesterol gradually increased during the 8-month study (58--485 mg/100 ml) but there was no significant difference between the acetate-fed and control groups. After 8 months, all rabbits had some degree of aortic intimal change. The changes involved a mean of 10% of the total aortic area. This involvement is much smaller than those previously reported and there was no significant difference between the acetate-fed rabbits and the control groups. Rabbit mortality was low (25%) and the mean weight increased from 1.7 to 2.7 kg. It is concluded that dietary acetate does not affect the rate and degree of development of hyperlipidemia and atherosclerosis. Furthermore, supplemental dietary Zn++ may have been responsible for the low rabbit mortality rate, weight gain and possibly the retarded development of atherosclerosis.

Acetates↗
PubMed1980

Benign lipoblastoma and myxoid liposarcoma: a comparative light- and electron-microscopic study.

A benign lipoblastoma and a myxoid liposarcoma were studied by light and electron microscopy. Both of these neoplasms had prominent plexiform vascular networks, early acquisition of fat by vascular pericytes, and progressive accumulation of fat by cells located away from the vasculature. Their component cells had investing basal laminae, pinocytotic vesicles, and cytoplasmic glycogen stores as well as cytoplasmic lipid. The process of neoplastic lipogenesis and the structural features of the neoplastic cells in both neoplasms resembled those of developing non-neoplastic fat tissue. The benign lipoblastoma appears to be analogous to developing fat, while the myxoid liposarcoma appears to recapitulate the actively proliferating zone of developing fat. The relationship between proliferating cells and the plexiform vascular network in all three processes is emphasized. We hypothesize that the vascular pericyte serves as a source for new fat storing cells.

Cytoplasm↗
PubMed1980

Respiratory distress syndrome from lymphangiography contrast medium.

Adult respiratory distress syndrome (ARDS) has been reported as a rare complication of lymphangiography with ethiodized oil. We report 2 patients who developed otherwise unexplained pulmonary edema after lymphangiography, and describe an animal model of pulmonary injury after an injection of ethiodized oil. We injected 0.25 ml/kg of body weight intravenously into 45 rabbits, and followed arterial blood gases and/or killed the rabbits randomly at various intervals for morphologic lung examination by light and electron microscopy. Within 24 h after injection, there was moderate hypoxemia from oil embolization, but only minimal lung edema. However, by 2 to 4 days after injections, hypoxemia was most severe and was accompanied by extensive alveolar and interstitial inflammation, hemorrhage, and edema. After 4 days, there was gradual blood gas and morphologic recovery, with complete restoration of normal anatomy by 6 wk. Our data showed that in rabbits, ethiodized oil can reproducibly cause delayed, severe pulmonary injury, thus supporting the clinical reports that ARDS may occur several days after lymphangiography.

Adult↗
PubMed1980

Mesotheliomas: a light- and electron-microscopical study concerning histogenetic relationships between the epithelial and the mesenchymal variants.

Mesotheliomas have variable histological patterns which may suggest a predominance of epithelial cells, a predominance of mesenchymal cells, or a mixture of epithelial and mesenchymal cells. An adenomatoid tumor of the testis, a fibrous mesothelioma, and an epithelial mesothelioma were studied by light and electron microscopy to search for evidence of a histogenetic link between the various cell types. Each neoplasm was composed of poorly differentiated spindle-shaped cells and variably differentiated cells having epithelial, mesenchymal, and combined epithelial and mesenchymal features. The differentiated neoplastic cells exhibited a spectrum of cytodifferentiation with typical mesothelial cells at one end, typical fibroblasts at the other end, and transitional forms in between. These observations are presented in detail as morphological evidence for a direct histogenetic relationship between the epithelial-appearing cells and the mesenchymal-appearing cells of human mesothelial neoplasms.

Adult↗
PubMed1979

Basal lamina of alveolar epithelium and capillaries: quantitative changes with aging and in diabetes mellitus.

Epithelial and capillary basal laminae (BL) of alveoli are significantly thicker in diabetics than they are in age-matched control subjects. The degree of thickening does not correlate significantly with patient age or with known duration of diabetes. The thickness of both types of BL in the lungs correlates significantly with thickness of BL in renal tubules and muscle capillaries. However, in muscle capillaries and in renal tubules, the BL deposits are 5 to 10 times greater than they are in the lungs. The effects of BL changes on pulmonary function remain to be explored.

Adolescent↗
PubMed1979

Characteristics of murine megakaryocytic colonies in vitro.

Characteristics of murine megakaryocytic colonies and their progenitor cells (CFU-m) were studied in vitro in agar gel. Colony growth required the presence of poke-weed-mitogen-stimulated spleen-conditioned medium. The number of colonies formed was linearly related to both the number of marrow cells plated and the amount of conditioned medium added. In addition, CFU-m were found in both the spleen and peripheral blood. Conditioned medium was also made without plasma, and this resulted in a cloning efficiency greater than that of conditioned medium prepared with plasma. The percentage of CFU-m in DNA synthesis was low (10%), as determined both in vivo and in vitro. Velocity sedimentation revealed that the majority of CFU-m sedimented at 4.3 mm/hr and had a tritiated thymidine (3H-TdR) suicide rate of 1.5 +/- 1.5%. A shoulder on the profile of CFU-m sedimented at approximately 6 mm/hr, with a suicide rate of 79 +/- 2%. Analysis of these data indicated that the majority of CFU-m were not in cycle or were in a long G1 period. The results suggest that CFU-m is a primitive progenitor, possibly closely related to murine splenic colony-forming units (CFU-s), analogous to erythroid bursts and granulocytic colony-forming units.

Animals↗
PubMed1975

Malakoplakia. Defect in digestion of phagocytized material due to impaired vacuolar acidification?

On the basis of light and electron microscopical findings in a case of malakoplakia of urinary bladder, (1) we concur with others that malakoplakia is a hyperplastic accumulation of histiocytes, and that the formation of Michaelis-Gutmann bodies is associated with incomplete digestion of phagocytized cell debris; (2) we hypothesize that digestion within phagolysosomes is impaired because of deficient acidification; and (3) we suggest that the defect in acidification in some cases may be related to treatment with drugs that affect the mechanism of phagocytic vacuolar acidification.

Carbonic Anhydrase Inhibitors↗