A new approach for clinical biological assay comparison and standardization: application of principal component analysis to a multicenter study of twenty-one carcinoembryonic antigen immunoassay kits.

Background: Principal component analysis (PCA) is a powerful mathematical method able to analyze data sets containing a large number of variables. To our knowledge, this method is applied here for the first time in the field of medical laboratory analysis.

Methods: PCA was used to evaluate the results of a blind comparative study of 21 carcinoembryonic antigen (CEA) reagent kits used to determine CEA concentration in a panel of sera from 80 patients.

Selective estrogen receptor modulators: Women's panacea for the next millennium?

The purpose of this review is to assimilate relevant experimental and clinical information available on selective estrogen receptor modulators with respect to their potential use as agents to improve women's health in the postmenopausal years. In addition, the mechanisms of action of these drugs are outlined. Selective estrogen receptor modulators represent an exciting group of antiestrogens that possess agonist action on bone, lipids, and lipoproteins and antagonistic action in the endometrium and breast.

Women's attitudes to and awareness of smear testing and cervical cancer.

A cross sectional survey consisting of a questionnaire of 650 randomly selected women aged 15 to 78 years was performed to gain an insight into women's attitudes to and awareness of smear testing and cervical cancer. Their general health and screening history were noted along with their knowledge of the smear test and cervical cancer. Of the respondents, 80.

Imbalances in serum proinflammatory cytokines and their soluble receptors: a putative role in the progression of idiopathic IgA nephropathy (IgAN) and Henoch-Schönlein purpura nephritis, and a potential target of immunoglobulin therapy?

Following recent experimental data suggesting an aggravating effect of circulating proinflammatory cytokines on the histological lesions of IgAN, we studied changes in serum proinflammatory cytokines and their soluble receptors and antagonists in patients treated with polyvalent immunoglobulins (15 with severe nephropathy who had indicators of poor prognosis: heavy proteinuria, hypertension, altered renal function and Lee's histological grade III or IV; and 14 with moderate forms of IgAN who had permanent albuminuria > 300 mg/day and < 2000 mg/day, Lee's histological grade II and a glomerular filtration rate > 70 ml/min) in comparison with healthy controls (n = 20) and patients with non-IgA nephritides (n = 50). These were measured by means of specific immunometric assays before and after 9 months of immunoglobulin therapy. Total tumour necrosis factor (TNF) serum and IL-6 levels were elevated in IgAN patients before therapy, relative to controls, and normalized after immunoglobulin therapy.

Analytical and clinical evaluation of an electrochemiluminescence immunoassay for the determination of CA 125.

The CA 125 II assay on the Elecsys(R) 2010 analyzer was evaluated in an international multicenter trial. Imprecision studies yielded within-run CVs of 0.8-3.

Ectopic pregnancy with levonorgestrel releasing intrauterine system.

The levonorgestrel releasing intrauterine system has been received with enthusiasm by all involved in women's health for both its contraceptive and non-contraceptive uses. This case illustrates a rare event and a possible note of caution.

The effects of tibolone.

Tibolone is a non-bleeding form of hormone replacement therapy (HRT). When ingested, it is broken down into metabolites, of which the progestogenic metabolite predominates at the level of the endometrium, so that an atrophic endometrium is produced. For the postmenopausal woman, the availability of non-bleeding HRT has great appeal, and compliance is substantially improved.

Review of 3,530 referrals for bone density measurements of spine and femur: evidence that radiographic osteopenia predicts low bone mass.

Purpose: To determine the relationship between bone mineral density (BMD) measurements and the initial reason for referral to a BMD screening service.

Materials And Methods: Referral letters for 3,479 of the 3,530 women referred for BMD screening were classified according to the indication for screening. Mean age-matched standard deviation scores (Z scores) were derived for each of the 10 most common indications.

The effects of ovarian hormone deficiency on wound contraction in a rat model.

Objective: To demonstrate the effect of a deficiency of ovarian hormones on the process of wound contraction, using the oophorectomised rat model of the human menopause.

Design: A randomised controlled trial.

Population: Ninety-six adult Wistar rats were randomly allocated into either an oophorectomised group or a sham-oophorectomised control group.

Elevated serum sialic acid in pregnancy.

Objective: Serum sialic acid has recently gained interest as a possible cardiovascular risk factor as well as a potential tumour marker. The effect of pregnancy on serum sialic acid is unclear particularly in the post-partum period.

Design: Longitudinal cohort.

Screening for osteopenia and osteoporosis: do the accepted normal ranges lead to overdiagnosis?

Osteoporosis is a common disease which causes significant morbidity and mortality and in many cases may be preventable. In the absence of fragility fractures the accepted method of identifying those at high risk is based upon bone mineral density (BMD) measurements with defined cut-off points. To correctly delineate normal from abnormal, reliable reference ranges appropriate to the observed population are required.

Hormone replacement therapy and cardiovascular disease.

Coronary heart disease is the principal cause of death in postmenopausal women. Postmenopausal women have an elevated cardiovascular risk profile in the form of android obesity (increased waist/hip ratio), hyperinsulinemia, impaired glucose tolerance, increased insulin resistance and elevated plasma LDL, VLDL, serum triglyceride and lipoprotein (a). A significant decrease in the relative risk of cardiovascular disease is observed with estrogen replacement therapy.

Hormone replacement therapy and serum angiotensin-converting-enzyme activity in postmenopausal women.

The mechanisms by which hormone replacement therapy (HRT) reduces the risk of coronary heart disease (CHD) are incompletely understood, but may include direct arterial effects. We examined the effect of oestrogen/progestagen HRT on serum angiotensin-converting-enzyme (ACE) activity in postmenopausal women. After 6 months, ACE activity was reduced by 20% (p < 0.

Comparison of six serum ferritin immunoassays and isoferritin spectrotypes in malignancies.

Serum ferritin was measured by six enzyme immunoassays in specimens from patients with digestive cancers (n = 30) and hematologic malignancies (n = 33). Most mean comparisons show significant differences in both groups of patients. In digestive cancers correlations between any two methods are very satisfactory (r > 0.

Effect of tibolone on postmenopausal bone loss.

A 2-year non-randomized prospective study was carried out in a teaching hospital menopause clinic to assess the effect on the skeleton of tibolone (Livial, Organon) 2.5 mg daily in recently postmenopausal women. One hundred women who were between 6 and 36 months since their last menstrual period and had raised gonadotrophin levels consistent with the menopause were allocated into two groups.

Aortic distensibility in post-menopausal women receiving Tibolone.

Both oestrogen and androgens have been shown to affect the structural composition and biophysical properties of the arterial wall in vitro. A non-invasive Doppler ultrasound technique, based on the measurement of pulse wave velocity along the thoraco-abdominal aortic pathway, was used to assess aortic compliance C in vivo in 49 normotensive, normal, healthy post-menopausal female subjects. 23 of the women had been receiving Tibolone, a synthetic steroid structurally related to norethisterone, for at least 3 years.

A study of the effect of tibolone on the vagina in postmenopausal women.

Tibolone is a synthetic compound with weak oestrogenic, progestagenic and androgenic properties. It does not appear to stimulate the endometrium, and therefore has appeal to the postmenopausal woman as a 'bleedfree' form of hormone replacement therapy (HRT). In the present study the vaginal cytological findings and symptoms were evaluated in 100 recently postmenopausal women, 50 of whom were started on tibolone 2.

Fractal signature analysis of macroradiographs measures trabecular organization in lumbar vertebrae of postmenopausal women.

High definition macroradiography was used to provide an image of the detailed structural organization of the cancellous bone in human lumbar vertebrae. The fractal signature analysis (FSA) method was used to quantify the horizontal and vertical trabecular organization recorded within the image. Comparison of the FSA of the postero-anterior and lateral macroradiographs in postmortem lumbar vertebrae showed that neither the superimposition of the neural arch nor the radiographic angle affected the trabecular measurement within the vertebral body.

The incidence of vaginal bleeding with tibolone treatment.

Objective: To determine the incidence of breakthrough bleeding and its significance in recently postmenopausal women who take tibolone (Livial-Organon).

Design: A two year comparative nonrandomised prospective study of women taking tibolone (2.5 mg) and control subjects not on medication.

Reducing unnecessary laboratory use with new test request form: example of tumour markers.

To limit the ordering of serum tumour marker tests that are clinically irrelevant, we designed a new request form. This is a matrix of boxes, rows being individual markers and columns body organs. The box at the intersection of line and column is colour-coded to indicate whether the test is appropriate or not.