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Biomedical subjects

T Ekfors

Publications and source records attributed to T Ekfors.

At least 55 records · Page 3Linked to original sources
PubMed1981

Thymic morphology during in vitro culture.

Morphology of guinea-pig thymic fragments was studied sequentially during in vitro organ culture by using light and electron microscopy and 3H-thymidine autoradiography. In culture the fragments became alymphoid. Thymic lymphocytes started to disappear first at the corticomedullary border, which gradually broadened, giving rise to the alymphoid epithelial fragments. As the lymphoid cells disappeared the thymic epithelium began to transform into a keratinized squamous epithelium. The keratinization started in the cells surrounding the Hassall's corpuscles, causing the enlargement of the corpuscles and finally total keratinization of the cultured epithelial fragments. In autoradiographic studies cell proliferation could be observed in uncultured thymuses at the cortical pericapsular area. In cultured alymphoid fragments labelled cells were distributed diffusely in the epithelium. Later labelling was concentrated to epithelial cells transforming to keratinized epithelium. Ultrastructural studies similarly showed transformation of the epithelial cells to squamous keratinized epithelium. The observation support the view that Hassall's corpuscles are derived from the keratinized thymic epithelium and that their existence is connected to the normal function of the epithelium.

Animals↗
PubMed1980

Asymmetric biphasic voltage stimulation of the osteotomized rabbit bone.

An experimental study was performed to determine the effect of electric current on the healing of osteotomies in the antebrachium of the rabbit. Starting with the assumption that the waveform of biphasic asymmetric voltage simulates the asymmetric pattern of stress-induced physiological electrical potentials in normal bone, biphasic asymmetric voltage was applied to the osteotomized radius or ulna. The effects of the electrical stimulation were evaluated by means of X-rays and histological studies. The voltage supplied induced periosteal proliferation whether implanted, insulated electrodes were employed or uninsulated external transfixation pins were used as electrodes. The stimulation had not only osteogenic but also chondrogenic effect. The external callus formation at the osteotomy sites and around the transfixation pins proved to be greater in the stimulated animals than in the controls.

Animals↗
PubMed1979

Pregnancy and small cell carcinoma of the uterine cervix.

A fatal case of a 22-year old pregnant patient with small cell cervical cancer is reported. The fulminant course of the disease was attributable more to the histological type of the tumour than to the pregnancy. Delay in diagnosis as a result of the pregnancy created a problem emphasized, by difficulty of cytological examination due to the very small size of the cancer cells.

Adult↗
PubMed1978

Malignant histiocytosis. Histiocytic medullary reticulosis.

Three cases of malignant histiocytosis occurring in children aged 2 months, 10 months and 14 years, are described. In all children the diagnosis was based on anaemia, granulocytopenia or thrombocytopenia, splenomegaly and marked erythrophagocytosis by bone marrow and lymph node atypical histiocytes. Two children aged 10 months and 14 years, underwent splenectomy after which combined chemotherapy with cyclophosphamide, vincristine and prednisone (COP) was started. In the older child a complete remission was achieved. The younger child died soon after the onset of the treatment. The youngest child was treated with bleomycin, adriamycin, cyclophosphamide, vincristine and prednisone (BACOP). He died of pneumonia and sepsis two months after the start of the treatment.

Adolescent↗
PubMed1977

Yersinia enterocolitica infection complicated by glomerulonephritis.

A case of mild glomerulonephritis in a 24-year-old man with clinical and immunohistological findings associated with Yersinia enterocolitica serotype 3 infection is described. The role of IgA in the pathogenesis of glomerulonephritis associated with mucosal infection is briefly discussed. Although attempts to demonstrate Y. enterocolitica 3 antigen in the biopsy specimen were unsuccessful, the glomerular deposits of immunoglobulins and complement suggest immune pathogenesis.

Adult↗
PubMed1975

Collagen metabolism in rat lungs during chronic intermittent exposure to oxygen.

Collagen metabolism was studied in rat lungs during prolonged intermittent exposure to oxygen. After an initial of 2-d exposure to oxygen, the rats alternately breathed air and oxygen in 24-h periods up to 30 d. Lung histology showed perivascular edema as an early sign of oxygen toxicity. Increased capillary permeability was followed by a marked perivascular leukocytosis that was prominent between the 5th and 11th d of the treatment. During the further course of the experiment, the inflammatory response gradually diminished, and finally a network of collagen fibres filled the perivascular areas. The inflammatory process elevated the amounts of DNA and RNA in lung tissue, and the ratio of RNA to DNA was maximal on the 5th day. Studies on metabolism of lung collagen with intraperitoneally injected 3H-proline as label showed that, after the initial inflammatory reaction, both synthesis and degration of collagen were increased in oxygen-treated lungs. The increase in synthesis exceeded the rise in degradation and, therefore, collagen was accumulated. The activation of lung collagen synthesis coincided in time with a rise in the activity of lung protocollagen proline hydroxylase.

Animals↗
PubMedDate not supplied

Summer spores of birch rust fungus in Papanicolaou smears from healthy mass screening participants.

OBJECTIVE: To evaluate the origin and identification of mysterious particles in Papanicolaou smears from healthy, asymptomatic women participating in a local mass screening program. STUDY DESIGN: The material consisted of 16,000 cerricovaginal smears studied at the cytology laboratory of Pathology Laboratory of South-Western Finland Ltd. Unidentified particles were found in four apparently independent smears. All the slides were rescreened, but no further positive cases were found. RESULTS: Several swab samples were collected from the investigation room, but all were negative. Attempts at identification included numerous consultations. A telepathology consultation with the Cellular Division, Armed Forces Institute of Pathology, Washington, D.C., U.S.A., was conducted. Another teleconsultation with the reference laboratoryfor intestinal parasites in Iceland was conducted. Finally, the Aerobiology Unit, University of Turku, was consulted. The aerobiologist suggested that the particles were most probably summer spores of birch rust fungus (Melampsoridium betulinum). To confirm this we obtained a reference specimen of the fungus from the herbarium at the University of Turku. The morphology of the spore particles was identical to that in the cervicovaginal smears, proving that the smears were contaminated with birch rust fungus spores. CONCLUSION: Birch rust is ubiqutitous in Finland. Outside the hospital window there is a wide lawn behind which, at a distance of 70 m, there is a forest of birch trees. It is most likely that the rust spores flew in through the open window, to settle down on the surface of material that was used in sample taking. Airborne dust may cause misleading and surprising artefacts. Protection of specimens and instruments against dust should minimize the problem.

Basidiomycota↗