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Janice Rymer, David Crook, Mandeep Sidhu, Michael Chapman and John C Stevenson

Objective:

To evaluate the effects of tibolone (Org OD14), a synthetic steroid used for the relief of postmenopausal symptoms, on serum concentrations of lipoprotein(a) (Lp(a)), an independent risk marker for coronary heart disease. Design: Subset of women participating in a non-randomized prospective trial of tibolone therapy. Twenty-seven women requesting relief of menopausal symptoms were treated with tibolone 2.5 mg/day for six months; 27 women who did not request treatment acted as controls. Results: Tibolone induced a substantial fall (p<0.001) in serum Lp(a) levels (median change −48%, range −100% to +3%). Conclusions: In terms of cardiovascular risk, the ability of tibolone to lower serum concentrations of Lp(a) may be advantageous in view of the unwanted reduction in high density lipoprotein concentrations which has previously been demonstrated in users of this steroid.

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Ralph W. Stevenson, Iain C. A. F. Robinson and John A. Parsons

Abstract.

Triglycyl-oxytocin (TGOT) and oxytocin (OT) were administered iv and sc to conscious dogs and the plasma concentrations of these peptides determined simultaneously by RIA and bioassay. Constant iv infusions (1 h) at 23 pmol/kg/min produced plateau levels of 1.1 and 1.6 pmol/ml plasma for OT and TGOT respectively. Whilst the distribution space was similar for each peptide, TGOT persisted longer in the circulation (t½, for TGOT 6.6 min; for OT 4.2 min). Bioactive values for OT followed RIA values whether this peptide was given iv or sc. Although very little bioactivity was generated by iv infusions of TGOT, considerable amounts of bioactive OT were found in plasma after injection of TGOT subcutaneously. The hormonogen proved relatively resistant to oxytocinase, an enzyme that destroys OT rapidly. Our results indicate that TGOT is converted to OT in vivo and that its action as a hormonogen is more pronounced after sc than iv administration.

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Panagiotis Anagnostis, Konstantinos Christou, Aikaterini-Maria Artzouchaltzi, Nifon K Gkekas, Nikoletta Kosmidou, Pavlos Siolos, Stavroula A Paschou, Michael Potoupnis, Eustathios Kenanidis, Eleftherios Tsiridis, Irene Lambrinoudaki, John C Stevenson and Dimitrios G Goulis

Objective/Design

Menopausal transition has been associated with a derangement of glucose metabolism. However, it is not known if early menopause (EM, defined as age at menopause <45 years) or premature ovarian insufficiency (POI, defined as age at menopause <40 years) are associated with increased risk of type 2 diabetes mellitus (T2DM). To systematically investigate and meta-analyze the best evidence regarding the association of age at menopause with the risk of T2DM.

Methods

A comprehensive search was conducted in PubMed, CENTRAL and Scopus, up to January 31, 2018. Data are expressed as odds ratio (OR) with 95% confidence intervals (CI). The I 2 index was employed for heterogeneity.

Results

Thirteen studies were included in the qualitative and quantitative analysis (191 762 postmenopausal women, 21 664 cases with T2DM). Both women with EM and POI were at higher risk of T2DM compared with those of age at menopause of 45–55 years (OR: 1.15, 95% CI: 1.04–1.26, P = 0.003; I 2: 61%, P < 0.002 and OR: 1.50, 95% CI: 1.03–2.19, P = 0.033; I 2: 75.2%, P < 0.003), respectively). Similar associations emerged when women with EM and POI were compared with those of age at menopause >45 years (OR: 1.12, 95% CI: 1.01–1.20, P < 0.02; I 2: 78%, P < 0.001 and OR: 1.53, 95% CI: 1.03–2.27, P = 0.035; I 2: 78%, P < 0.001), respectively).

Conclusions

Both EM and POI are associated with increased risk of T2DM.