Stearoyl paratoluenesulfonate. A powerful acylating agent for lipid synthesis

The utility of the mixed carboxylic-sulfonic acid anhydride stearoyl p-toluenesulfonate as a powerful, mild acylating agent for lipid synthesis is shown by the synthesis of rac 1,2-distearoyl-3-iodopropane, lecithin and a spin-labeled choline derivative from the corresponding alcohols. The method constitutes a significant improvement of earlier acylating methods.     

Acupuncture analgesia and cesarean section

The application of acupuncture anesthesia in obstetrics is discussed and reviewed. Of 14 patients delivered by cesarean section under acupuncture, 8 (57%) felt no pain, and 6 did not go through the entire procedure without other supplementary anesthesia. The failure and success rates are reviewed. It is suggested that the technique be evaluated further because with acupuncture the fetus and mother are completely protected from the secondary effects of general regional anesthesia.     

Results of cemented metal-backed acetabular components: a 10-year-average follow-up study

We have developed a computer program for the rapid assessment of the primary structure differences between a protein of unknown sequence and a homologous known protein. Both proteins are reduced, alkylated, and digested with the same hydrolytic agent. The unfractionated peptide mixtures are submitted to automatic sequence analysis. Based on the knowledge of the reference sequence, the program utilizes the analysis data to identify all the potential peptides present in the two mixtures, determining their primary structure, homology degree, and molecular weight calculated both as integer MH+ and average mass variables. These fingerprints allow the user to easily identify the structural differences between the two proteins and clarify possible doubts by a mass spectrometric analysis of the two mixtures. In order to verify the utility of the program, we provide an application example using the already reported data of two homologous proteins.     

Antithrombotic potency of hirudin is increased in nonhuman primates by fibrin targeting

BACKGROUND: Inhibition of thrombin by either the indirect thrombin inhibitor heparin or by more potent direct thrombin inhibitors such as hirudin reduces thrombus formation after arterial injury. The present study was designed to determine if a fibrin-specific thrombin inhibitor could, by local thrombin inhibition, prevent thrombosis more effectively. METHODS AND RESULTS: We first studied antithrombotic potency in vitro, comparing fibrin-targeted hirudin (recombinant hirudin covalently linked to the Fab' fragment of the anti-fibrin monoclonal antibody 59D8) to recombinant hirudin in baboon plasma. Fibrin-targeted hirudin was nine times more effective than recombinant hirudin in inhibiting fibrin deposition on experimental clot surfaces in baboon plasma (P < .01). The potency of fibrin-targeted hirudin was then compared with that of recombinant hirudin in a baboon model of thrombus formation. 111In-labeled platelet deposition was measured in a synthetic graft segment of an extracorporeal arteriovenous shunt in control animals and in animals receiving either fibrin-targeted hirudin or hirudin. In these experiments, fibrin-targeted hirudin was 10-fold more potent than hirudin in inhibiting platelet deposition and thrombus formation (P < .05). CONCLUSIONS: These data indicate that targeting a thrombin inhibitors such as hirudin to an epitope present in thrombi results in increased antithrombotic potency.     

Psychological disorder and mortality in French older adults: do social relations modify the association?

The possible modifying effect of social relations on the association between depression and mortality was examined in a community-based cohort study. A total of 3,777 randomly selected persons 65 years of age and older in southwest France were followed over a 5-year period from 1988 in the Personnes Agees Quid (PAQUID). At study entry, the prevalence of elevated depressive symptomatology was 12.9% for men and 14.7% for women, and the reported relative isolation was 14.1% for men and 26.0% for women. During a total of 16,984 person-years of follow-up, 849 deaths occurred. Among participants with high levels of depressive symptomatology, the age-adjusted mortality rate ratio was 2.10 (95% confidence interval 1.7-2.7) in men and 1.76 (95% confidence interval 1.4-2.3) in women. When compared with individuals with the most connections, men and women with few social network connections were also at increased risk of mortality: age-adjusted rate ratio = 2.69 (95% confidence interval 1.9-3.8) for men and 1.56 (95% confidence interval 1.0-2.4) for women. Satisfaction with social support had a small but nonsignificant effect on mortality risk. For women, the excess risks due to depressive symptoms and few network connections are observed only in the 65- to 74-year age group, after adjusting for health and health behaviors. Social relations did not significantly modify the depression-mortality associations for either men or women, although the depression-mortality effect was reduced by 12.8% in men. The latter findings do not appear to be compatible with the buffering hypothesis, whereby we would expect social relations to decrease the depression-mortality association. Nonetheless, there are independent effects from these two factors, and older men who are depressed and not socially connected are at increased risk of dying earlier.