Fondaparinux is a pentasaccharide that selectively inhibits coagulation factor Xa. It is administered by subcutaneous injection and does not require laboratory monitoring. This large study compared fondaparinux and unfractionated heparin in the initial treatment of symptomatic pulmonary embolism. Fondaparinux was as effective and safe as heparin.

Fondaparinux may be used as an alternative to intravenous heparin in the initial treatment of hemodynamically stable patients with symptomatic pulmonary embolism.

The efficacy of ximelagatran, an orally administered thrombin inhibitor, was compared with that of warfarin for thromboprophylaxis after total knee replacement. Both drugs were given for 7 to 12 days postoperatively, ximelagatran at a dose of 24 or 36 mg twice daily and warfarin with a target international normalized ratio of 2.5. The higher dose of ximelagatran was superior to warfarin in the prevention of venous thrombosis.

Ximelagatran does not require coagulation monitoring and hence can be given at a fixed dose. The short-term efficacy of this drug is promising, but its value for long-term anticoagulation is still unclear.

Ximelagatran, a direct inhibitor of thrombin, is administered orally, and its use does not necessitate monitoring of coagulation. In this study, patients treated for venous thromboembolism with warfarin for six months were randomly assigned to receive ximelagatran or placebo. During the subsequent 18 months, the patients in the ximelagatran group had many fewer episodes of recurrent thromboembolism than those in the placebo group, without an increase in the frequency of bleeding.

A direct comparison of ximelagatran and warfarin for secondary prevention is needed before conclusions about therapy can be drawn. In addition, ximelagatran therapy caused elevations of the alanine aminotransferase level in some patients, a problem that will require further evaluation.

Because mutations in the parafibromin gene (HRPT2) occur in a familial syndrome characterized by susceptibility to parathyroid carcinoma, such mutations were sought and found in patients with sporadic cases of parathyroid carcinoma. Moreover, germ-line mutations of HRPT2 were found in some patients with apparently sporadic parathyroid carcinoma.

Mutations in HRPT2 probably have a causative role in parathyroid carcinoma. The finding of germ-line mutations of the gene in apparently sporadic cases points to a variant of the familial syndrome with low penetrance and raises questions about the value of genetic testing in carriers of the mutant gene.

Mercury poisoning still occurs as a result of accidental and occupational exposure. For the general population, however, the main concern is the possible adverse effect of exposure to mercury through fish consumption and the receipt of dental amalgams and thimerosal, a preservative used in vaccines. This review summarizes both the facts and the controversies surrounding exposure to methyl mercury, mercury vapor, and the ethyl mercury in thimerosal.

Schizophrenia has varied and ominous symptoms that generally begin in late adolescence or early adulthood and usually continue throughout life. This Drug Therapy article discusses the new generation of antipsychotic medications, as well as recent developments in brain imaging and in knowledge of the pathophysiology and molecular genetics of this devastating disease.

Despite advances, schizophrenia, which affects 1 percent of the population, remains an enigmatic illness that places a substantial burden on patients, their families, and society.

This Sounding Board article reviews the available evidence and concludes that — at least at present — cerebral palsy is not preventable in the vast majority of cases.

This conclusion has medicolegal implications for many claims relating cerebral palsy to malpractice by physicians.