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Biomedical subjects

B S Thomas

Publications and source records attributed to B S Thomas.

At least 37 records · Page 2Linked to original sources
PubMed1988

Sex hormone-binding globulin and the natural history of breast cancer.

Low concentrations of SHBG in the blood appear to be related to rapid tumour growth rates whereas normal values are associated with slower rates. The inferences drawn from these and other experimental results are as follows: 1. It is no longer necessary to postulate that an abnormal endocrine environment is related to the risk of breast cancer. 2. Variation within the normal range of endocrine function may be sufficient to account for marked differences in the growth rates of transformed cells. 3. It is suggested that women whose tumours arise in an environment characterised by SHBG concentrations at the lower end of the normal range (and, hence, non-SHBG-bound oestradiol levels at the top end of the range) will tend to have an earlier age at diagnosis, a lower frequency of oestrogen-receptor positive tumours and a lower proportion of hormone responsive tumours than women with SHBG levels at the top of the range. 4. Case/control studies in which growth rates are not taken into account may be difficult to interpret.

Adult↗
PubMed1986

Thyroid function and the incidence of breast cancer in Hawaiian, British and Japanese women.

Serum-free thyroxine (FT4) concentrations are lower in Hawaiian and Hawaiian Caucasian women than in Hawaiian Japanese, Hawaiian Filipino, Hawaiian Chinese, and English and Japanese mainland women. There is a high inverse correlation between FT4 and risk of breast cancer in these ethnic groups. Thyroid-stimulating hormone (TSH) concentrations, which are inversely correlated with FT4, generally show the same relationship.

Adult↗
PubMed1986

Instructional computing in American nursing programs.

This paper summarizes more than a decade of progress on computing in nursing education and reports the results of a two-phase study of instructional computing in American nursing programs. The study reveals an enormous range of activity in nursing education, the importance of various barriers to growth and use of computers and the perceptions of deans and directors of potential remedies and the feasibility of each.

Computer-Assisted Instruction↗
PubMed1986

Identification of women at high risk of breast cancer.

Prospective studies of risk factors for breast cancer have been carried out since 1961 on a normal population which now comprises some 15,000 women. Classical (anamnestic) factors such as ages at menarche, menopause, or at first child, post-menopausal weight and high parity are not strong determinants of risk. Measurements of various aspects of endocrine function are more successful in identifying women at risk, as is assessment of mammographic parenchymal patterns but, again, these variables are not effective enough to make an intervention strategy imperative. However, the combination of classical, endocrinological, and radiological factors appears to achieve this aim. A substantial sub-set of women who have a four-fold risk of breast cancer may be identifiable.

Adult↗
PubMed1984

Urinary androgen and 17-hydroxylated corticosteroid metabolites and their relation to recurrence rates in early breast cancer.

The amounts of urinary androsterone and etiocholanolone are highly correlated with recurrence rates in patients with early breast cancer after treatment by mastectomy. A more efficient means of predicting the clinical course of the disease is obtained by using a ratio of these compounds to the amounts of individual 17-hydroxycorticosteroids in the urine. For instance, the ratio of androsterone to alpha-cortolone is particularly effective in identifying women with a high rate of recurrence, and this is largely independent of pathological stage and tumor grade.

17-Hydroxycorticosteroids↗
PubMed1984

Effect of prednisolone on hormone profiles during primary endocrine treatment of advanced breast cancer.

Various plasma hormones were measured in 13 pre- and 20 post-menopausal women with advanced breast cancer before and for 12 months after ovarian irradiation or during continuous administration of tamoxifen at a dose of 10 mg twice a day, respectively; some patients received additional prednisolone at a dose of 5 mg twice a day. These patients were taken from a larger clinical trial which demonstrated a higher response to primary endocrine therapy when prednisolone was added. Levels of dehydropiandrosterone sulfate were depressed in patients receiving prednisolone, confirming adrenal suppression. Estradiol levels were reduced in all patients, while luteinizing hormone and follicular stimulating hormone increased after ovarian irradiation, but all three hormones fell during tamoxifen administration; no further changes were caused by the addition of prednisolone. Prolactin and thyroxine remained constant throughout the study. There were no differences between responders and nonresponders in hormone profiles or in changes in the profiles after treatment.

Breast Neoplasms↗
PubMed1983

A prospective study of urinary androgen levels and ovarian cancer.

The three major urinary androgen metabolites, dehydroepiandrosterone (DHEA), androsterone (ANDRO), and aetiocholanolone (AETIO) were measured in 1,484 volunteer women between 29 and 60 years of age on the island of Guernsey from 1962-1967. Twelve of these women subsequently developed ovarian cancer after a median interval of 130 months and a minimum interval of 19 months. All three androgen levels in these women were lower than those in controls matched for age and menopausal status. The results were most striking for DHEA, where half of the cases were below the 27th percentile of their matched controls (p = 0.007, two-sided). The results for ANDRO were of marginal significance (p = 0.06), and those for AETIO were not significant (p = 0.33).

Adult↗
PubMed1983

Thyroid function in early breast cancer.

Serum 'free thyroxine' was measured as a thyroid function index (TFI) in 238 women with early breast cancer and 107 normal controls. The mean TFI was significantly lower in the cases compared with controls. The TFI was not related to pathological stage but correlated with histological grade, with the highest values found in well-differentiated (grade I) and the lowest in anaplastic tumours (grade III). A similar result was obtained with the urinary and androsterone:aetiocholanolone (5 alpha:5 beta) ratio in that the ratio was significantly lower in patients with grade III than in those with grade I tumours. These results indicate that thyroid hormones may be involved in tumour cell differentiation. Patients with low 5 alpha/5 beta ratios had significantly faster recurrence rates than those with high ratios. A similar trend was found for the TFI. The TFI decreases after mastectomy and at 12 months after operation is still below the pre-operative basal level.

Adult↗
PubMed1982

Urinary androgen metabolites and recurrence rates in early breast cancer.

Androsterone and aetiocholanolone were measured in urine specimens obtained from 218 women with early breast cancer. Patients who excreted less than the median amount of these steroids had a significantly higher recurrence rate (P less than 0.005) than patients excreting more than the median value. The relationship between androgen excretion and recurrence is stronger in pre-menopausal women that in the post-menopausal group. The androgen assays are still associated with recurrence rates when patients are stratified by pathological stage, but no clear relationship was found with histological grade.

Androsterone↗
PubMed1976

Method for the measurement of plasma dehydroepiandrosterone by gas-liquid chromatography with electron capture detection.

A method is described for the measurement of plasma dehydroepiandrosterone, as the iodomethyldimethylsilyl ether derivative, by gas-liquid chromatography and electron capture detection using the relatively new and highly stable stationary phase Dexsil 300. Preliminary purification of the plasma extract was required and alumina column chromatography was utilised, both before and after derivatization of the steroid extract. Specificity, precision, sensitivity and accuracy were all satisfactory. The method was used to study the relationship between age and the level of plasma dehydroepiandrosterone in a group of normal women. A significant negative correlation was observed.

Adolescent↗