Thromboembolic complications of pregnancy and oral contraceptives

Diversity and versatility of p38 kinase signalling in health and disease

The ability of cells to deal with different types of stressful situations in a precise and coordinated manner is key for survival and involves various signalling networks. Over the past 25 years, p38 kinases — in particular, p38α — have been implicated in the cellular response to stress at many levels. These span from environmental and intracellular stresses, such as hyperosmolarity, oxidative stress or DNA damage, to physiological situations that involve important cellular changes such as differentiation. Given that p38α controls a plethora of functions, dysregulation of this pathway has been linked to diseases such as inflammation, immune disorders or cancer, suggesting the possibility that targeting p38α could be of therapeutic interest. In this Review, we discuss the organization of this signalling pathway focusing on the diversity of p38α substrates, their mechanisms and their links to particular cellular functions. We then address how the different cellular responses can be generated depending on the signal received and the cell type, and highlight the roles of this kinase in human physiology and in pathological contexts.

p38α — the best-characterized member of the p38 kinase family — is a key mediator of cellular stress responses. p38α is activated by a plethora of signals and functions through a multitude of substrates to regulate different cellular behaviours. Understanding context-dependent p38α signalling provides important insights into p38α roles in physiology and pathology.

Pulmonary embolism

Contemporary concepts in the diagnosis, treatment and natural history of pulmonary embolism are reviewed, and a practical rationale for investigation and therapy is outlined.

Testosterone inhibits prostacyclin production by rat aortic smooth muscle cells in culture

The effects of testosterone on cell proliferation and prostacyclin production were investigated using rat aortic smooth muscle cells in culture. Testosterone at 10(-10)-10(-6) M did not have any significant effect on cell proliferation, but it significantly inhibited prostacyclin production by the cells. Maximal inhibition of prostacyclin production (70%) was observed when cells were treated with a physiological concentration of 19(-8) M testosterone for 5 consecutive days. These results suggest that testosterone may stimulate thrombus formation and accelerate atherosclerosis by suppressing prostacyclin production in arterial smooth muscle cells.

The effect of chlorotrianisene as postpartum lactation suppression on blood coagulation factors

Coagulation changes and increased risk of thromboembolic disease may occur in association with estrogen administration. The puerperium is also a high-risk period for thromboembolism, and estrogen administration at this time may increase this risk. Patients with congenital deficiency of antithrombin III have recurrent venous thromboembolic disease, suggesting that low levels of this factor may be associated with "hypercoagulability" states. We studied 50 postpartum patients who received chlorotrianisene (Tace) or placebo for lactation suppression in a prospective, double-blind, randomized fashion. Antithrombin III values were significantly lower on the third day post partum in the treated group compared to the placebo group (p less than 0.05). In addition, our clinical data from a total of 99 patients support the previous evidence that estrogens delay rather than prevent breast engorgement. Thus, with questionable benefit and a possible increased thromboembolic risk, it would appear prudent to discontinue the practice of estrogen administration for lactation suppression.

Successful pregnancy following myocardial infarction: a case report

A case of successful pregnancy following myocardial infarction is reported. The literature on this subject is reviewed and discussed. It is concluded that, if sufficient time is allowed for healing, pregnancy following myocardial infarction is associated with little or no maternal or fetal mortality. A plan of obstetrical management is outlined.