Search PubMed⌕ Search

Biomedical subjects

P Selby

Publications and source records attributed to P Selby.

136 records · Page 8Linked to original sources
PubMed1983

Treatment of advanced malignant melanoma with high-dose melphalan and autologous bone marrow transplantation.

Twenty-eight patients with advanced life-threatening metastatic malignant melanoma were treated with high dose (140-260 mgm-2) intravenous melphalan and autologous bone marrow. Cyclophosphamide "priming" 300 mgm-2 i.v. was given to 19 patients one week previously and this resulted in clinical but not histological evidence of amelioration of gastrointestinal toxicity. In 11 patients (43%) there was evidence of tumour response to treatment and in 2 patients complete remissions were observed. However in most patients, responses were short-lived and no patient lived longer than 17 months from start of treatment or 24 months from first recorded evidence of distant metastatic disease.

Adult↗
PubMed1979

[Control of sexually transmitted diseases in Senegal].

STD are an important public health problem in numerous developing countries. Although satisfactory diagnostic and therapeutic means are available, the incidence of STD is increasing. Among the causes for this are sociological factors, like the weakening of customs and the family unit, and the development of tourism, which stimulates prostitution. There is a marked ignorance of the population in respect to STD. The Senegalese Government, WHO, and the Geneva-based Sandoz Institute launched in 1976 a joint programme of service, training and sesearch. The research aims at developing a preventive approach, especially through health education. While the three centers set up have accomplished good work locally, results are still disappointing from a public health point of view. Weak spots are in particular: - inadequacy of the social and contact-tracing services; -lack of action at the periphery and of integration with primary health care; -lack of coordination with other sectors (including police), and with professionals of various disciplines who should contribute to the socio-economic investigation of the problem. Several groups have recently been created in Senegal to support the project. An evaluation will soon be carried out. Such programmes should be implemented in other countries of the region.

Female↗
PubMed1979

Patterns of maturation in short-term culture of human acute myeloid leukaemic cells.

Leukaemic cells taken from the blood of patients with acute myelogenous leukaemia (AML) frequently proliferate in suspension culture without the addition of growth factors for a limited period only. After a 6--10-fold increase in total cells, cell numbers remain constant for a time and finally decline. The main cause for this limited growth in vitro is not, initially at least, cell death leading to a steady state, but maturation associated in its final stages with cessation of DNA synthesis. Two populations of AML cells from Patients St and Wi respectively were studied, and progressive maturation towards mature leucocytes was demonstrated by the gradual acquisition in culture by the growing blast cells of intracellular enzymes (lysozyme, arginase, acid phosphatase and esterase being measured), surface markers (Fc and C3 receptors), of lactoferrin by Wi cells and of colony-stimulating activity by St cells, as well as changes in Ia antigens, phagocytic properties, morphology and adhesiveness to plastic. With St cells, which carried a characteristic chromosome marker, maturation terminated in cells with the characteristic properties of macrophages. At an intermediate stage, non-adherent and still-dividing St cells acquired Fc and C3 receptors and enzymes characteristic of monocytes. Wi cells progressively became neutrophil-like, and again there was an intermediate population of dividing cells which had Fc and C3 receptors and proteins such as lactoferrin and esterases. characteristic of neutrophils.

Cell Adhesion↗
PubMed1979

Spontaneous regression of human acute myeloid leukaemia xenografts and phenotypic evidence for maturation.

A population of human AML cells which have a characteristic karyotypic marker was cryopreserved and then grown in short-term liquid culture for 2 weeks, during which time the cells increased about 7-fold in number and progressively acquired characteristics of macrophages. 10(7) cells obtained after 1 day in culture, when they were almost devoid of Fc receptors (Fc-), on inoculation into immune-deprived mice gave rise to tumours in more than 90% of the animals. However, after 13 days of culture, when almost all the cells had Fc receptors (Fc+), a similar inoculum did not grow as tumours. After 7 days in culture the cells were heterogeneous, and divided about equally into Fc+ and Fc- cells, both of which were replicating. The Fc- population was capable of producing tumours, whereas the Fc+ was not. Of 23 assessable xenograft tumours produced by the AML cells, 14 regressed completely, 4 grew progressively and 5 grew progressively after initial regression. Progressive tumours could be further transplanted. The regression may arise as a result of maturation in vivo similar to that seen in vitro.

Animals↗
PubMedDate not supplied

Therapeutic implications of a stem cell model for human breast cancer: a hypothesis.

A model for human breast cancer is proposed in which a subpopulation of relatively undifferentiated tumor stem cells gives rise to clones of cells by a process of exponential division. The progeny progressively become more differentiated but lose their proliferative potential. The model implies that breast cancers are heterogeneous with respect to differentiation features such as hormone receptors, both between different clones and within individual clones. Therefore, endocrine therapies are preferentially directed towards differentiated cells and are unlikely to be curative either in advanced disease or in the adjuvant setting. The reduction of differentiated cells by hormonal maneuvers may leave a population of more actively dividing tumor stem cells which are more sensitive to chemotherapy. Hormonal therapy followed by cytotoxic chemotherapy may be more likely to kill tumor stem cells than either form of therapy given alone.

Breast Neoplasms↗