Biomedical subjects

K W Hancock

Publications and source records attributed to K W Hancock.

54 records · Page 3Linked to original sources

PubMed1976

Significance of low body weight in ovulatory dysfunction after stopping oral contraceptives.

In a group of patients who developed ovulatory dysfunction on stopping oral contraception the mean body weight of those with previosly regular cycles was significantly lower than that of women who had had ovulatory dysfunction beforeoral contraception and also that of a control group. Women of low body weight may be at particular risk of developing post-pill amenorrhoea even when there is no history pointing to ovulatory dysfunction. This should be considered when selecting a form of contraception in such women.

Amenorrhea↗

PubMed1976

Effect of length of gestation on maternal cellular immunity to human trophoblast antigens.

Maternal lymphocyte reactivity to human trophoblast antigens was studied in placentas of gestational ages 8 to 14 weeks and 32 to 34 weeks, respectively. Significant trophoblast lysis became apparent after 24 hours' incubation in the latter case compared with a time lag of 72 hours in the terminated gestations. Maternal cellular immunity, therefore, was not detected during the first 3 1/2 months of pregnancy, but was detectable by the time of parturition. The possible significance is discussed with respect to the antigenic stimulus and survival of the fetal allograft.

Antigens↗

PubMed1976

Plasma solute concentrations during gonadotrophin-induced ovulation.

The effects of ovulation induction on some plasma solute concentrations were investigated serially in eleven women, nine of whom conceived in that cycle. Increasing oestrogen output during the follicular phase was associated with decreasing levels of osmolality, urea, total protein and the albumin free protein fraction. Smaller decreases in the concentrations of sodium, potassium, chloride, carbon dioxide combining power (CO2CP) and albumin were not statistically significant. The luteal phase was marked by a rise in osmolality and a fall in CO2CP but no other significant changes. Levels of osmolality, sodium and potassium fell in early pregnancy when oestrogen output was further increased. These results appear consistent with an oestrogen induced expansion of the extracellular fluid compartment by retention of water in excess of solute, which might also account for the similar changes in pregnancy.

Blood Proteins↗

PubMed1976

Haematological changes during ovulation-induction by gonadotrophins.

The oestrogen response to ovulation-induction by gonadotrophins initiates a preovulation rise in total leucocytes and promotes fluid retention. In consequence of the latter, cyclic changes occur in blood haemoglobin and the haematocrit. The level of oestrone excretion in the follicular phase of induced cycles indicates that multiple follicular development probably occurs, and this also appears to affect the luteal phase. It seems likely, therefore, that the data present a rather exaggerated picture of the situation which obtains in normal menstrual cycles.

Blood↗

PubMed1975

Antigenicity of trophoblast and possible antigen-masking effects during pregnancy.

The interaction between cultured human trophoblast cells and materanl lymphocytes was used as an in vitro model to investigate trophoblast antigenicity. Cytotoxic effects in the trophoblast monolayer were apparent after 72 hr incubation and depended on the presence of non-lymphoid cell types in addition to lymphocytes. Lysis of trophoblast was preceded by blast cell formation and apparently involved close contact between the maternal cells and the trophoblast cells. The nature of the cytotoxic reaction suggested the presence of histocompatibility factors on trypsinized trophoblast cells. This manifestation could be due to removal of fibrinoid or enhancing antibody from the cultured cells. The ability of trypsinized trophoblast cells to synthesize mucoprotein was investigated by the Hale colloidal iron test and found to be unimpaired. The effect of maternal serum on the recognition of human trophoblast antigens by maternal lymphocytes was used as an in vitro model to investigate the occurrence of enhancing antibody in maternal serum. The cytotoxic effects of maternal lymphocytes on trophoblast were completely prevented by the presence of maternal serum, this protective effect being reduced significantly by removal of IgG from the maternal serum. A slight protective effect of allogeneic pregnancy serum was also observed. It is suggested that these findings support a role for immunological enhancement in maintaining the foetal allograft.

Antigens↗

PubMed1974