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Biomedical subjects

B Daunter

Publications and source records attributed to B Daunter.

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

The reversal immune surveillance hypothesis: part II.

The first part of the reversal immune surveillance hypothesis (RISH. I) describes the conceptual framework of the immune system as a homoeostatic mechanism for the control of cell differentiation and replication. The thymic dependent lymphocytes (T-cells) are considered to be tissue specific and identify aberrations in the cell surface pattern (antigens), that represent that particular cell type. The T-cells may then recruit antibody forming B-lymphocytes (B-cells) to produce antibodies (humoral response) to the cell surface antigens in order to return the cell surface pattern to its correct state. The antigens may also be removed from the cell surface as immune complexes by the complement system, which under normal conditions does not cause cell lysis. The cellular arm of the immune system, that of killer cells or activated macrophages are considered to be primarily involved with tissue remodelling. Whether or not the humoral or cellular arm of the immune system is activated depends upon the antigens displayed by the stimulating cell. The proposed system, which is self monitoring, is considered to have evolved from the invertebrates through to the vertebrates to become more complex in the mammals. Therefore the immune system is considered to be based on the identification of self and self-foreignness, rather than on foreignness per se.

Animals↗
PubMed1981

A comparison of the physicochemical properties of carcinoembryonic antigen in extracts of tumour tissue, ascitic and cyst fluid from ovarian cancer.

In view of the reported disagreement in the physicochemical properties of ovarian carcinoembryonic antigen (CEA), this study was undertaken to compare the properties of CEA obtained from extracts of ovarian tumour tissue, ascitic fluid and cyst fluid. On the basis of molecular weight estimation and binding properties with Concanavalin A and wheat germ lectin, ovarian CEA from these three sources appeared similar, and also possessed similar properties to those of colonic CEA. On isoelectric focusing, however, it was found that the isoelectric point of CEA from tumour tissue and cyst fluid differed from that from ascitic fluid. It is most likely that this is due to a loss of sialic acid from the CEA released into ascitic fluid.

Ascites↗
PubMed1980

The beta-subunit of chorionic gonadotrophin as a tumour marker in gestational trophoblastic disease.

The clinical usefulness of the serum level of the beta subunit by radioimmunoassay was evaluated in 96 patients with gestational trophoblastic disease. The measurement of the hormone-specific beta subunit has allowed a better understanding of the activity of the various types of disease, with a correlation between the initial serum levels and the different subtypes of hydatidiform mole, and the ability to predict the development of malignant sequelae. The phenomenon of trophoblastic persistence after uterine evacuation was confirmed: although the half-life of the beta subunit was 4 days during the early phase, there was an average period of 8 weeks before levels fell to negative and 12 weeks was the limit for spontaneous regression. The serial beta subunit levels were found to provide an accurate indication of the clinical course of the disease in untreated and treated patients, and treatment could be withheld after 3 consecutive weekly negative values.

Choriocarcinoma↗
PubMed1979

The reversal immune surveillance hypothesis.

The proposed reveral immune surveillance hypothesis is based on the identification primarily of self and secondarily of foreignness, unlike the original hypothesis that is based on the identification of foreignness per se. The proposed system is considered to have evolved from the invertebrates through to the vertebrates to become more complex in the mammals, and involves the identification of cell types by lymphocytes through the cell type surface pattern and major histocompatibility antigens. The identification of self and associated foreignness by the immune system is required for the regulation of cell differentiation and replication, and because of this design, the ability of the immune system to destroy foreignness can be regarded as a natural consequence. The reversal immune surveillance hypothesis explains why spontaneously occurring tumours may not be antigenic, in the sense of eliciting their own destruction, and is consistent with the destruction of tumour cells that display significant amounts of viral antigens or gross antigenic changes induced by carcinogenic agents. It is also able to explain the stimulation and inhibition of tumour development.

Animals↗
PubMed1976

The scanning electronmicroscopy of human cervical mucus in the non-pregnant and pregnant states.

The ultrastructure of the high viscosity phase of human cervical mucus was studied by scanning electronmicroscopy. In the normal woman, sequential mucus samples taken throughout the menstrual cycle showed a honeycomb-like structure with interconnecting channels separated by thin membraneous walls. The diameter of the channels in the mucus was 2 to 6 mum in the early follicular phase, 30 to 35 mum in the late follicular phase and 4 to 6 mum in the luteal phase. During the first trimester of pregnancy and also at the beginning and end of the menstrual cycle a compact, dense form of mucus structure was observed. In women using either copper-releasing or pharmacologically inert intrauterine contraceptive devices (IUCDs), the basic structure was similar to that seen in normal women. The channel diameters were normal in women using the inert IUCD but the mucus from women using a copper-releasing IUCD showed a slight decrease in the late follicular phase channel diameter which was dependent on the time the device had been in place. Globular appendages to the membraneous walls of the mucus were observed in the presence of a copper-releasing IUCD.

Cervix Mucus↗