Effect of ionenes on structure and catalytic activity of cobaltphthalocyanine, 1. Visible light spectroscopic investigations

The structural behaviour of cobalt(II)phthalocyanine-tetrasodium sulfonate (CoPc(NaSO₃)₄) ( 1 ), a catalyst used in thiol oxidation, was investigated in the presence of ionenes (poly-quaternary ammonium salts), ( 2 ) using visible light spectroscopy. It was observed that ionenes, which have been shown to promote the catalytic activity, strongly enhance the aggregation of the cobalt complex. No cobalt site isolation occurred up to N⁺/Co = 10⁵. Furthermore, a stoichiometric CoPc(NaSO₃)₄/ionene complex appeared to be formed with an N⁺/Co-ratio of 4:1. This ratio was found to hold for ionenes with M?_n varying from 6 100 to 22 000 and charge densities from 0,8 to 1,5. As the charge density was increased, the observed CoPc(NaSO₃)₄ spectrum was more affected. Experiments with oxygen in alkaline solution revealed that the complex was resistant toward oxygen adduct formation in the presence of ionenes. This phenomenon is discussed in relation to the catalytic activity of the system.     

The proapoptotic 9-2 isozyme of 2-5 (A) synthetase cannot substitute for the sperm functions of the proapoptotic protein, Bax.

The 9-2 isozyme of 2-5 (A) synthetase has cellular proapoptotic functions that are mediated not by enzyme activity but by the Bcl-2 homology domain 3 present in its unique carboxyl-terminal region. Another proapoptotic cellular protein is Bax, whose absence in the Bax(-/-) mice causes male sterility due to abnormal sperm differentiation. In this study, we examined whether transgenic 9-2 expression can substitute for the in vivo reproductive function of Bax. To achieve this goal, a sperm-specific promoter was used to drive the expression of 9-2 in the sperm of transgenic mice. By selective cross-breeding, the transgene was transferred to Bax(-/-) mice to generate the experimental mouse line (Bax(-/-), 9-2(+/+)). The male experimental mice were sterile, and their testes maintained the structural abnormality found in Bax(-/-) mice. Thus, the male reproduction functions of Bax could not be replaced by the 9-2 isozyme of 2-5 (A) synthetase.     

Adenoviral vectors do not induce, inhibit, or potentiate human platelet aggregation.

Adenoviruses are commonly used as vectors in human clinical gene therapy trials. High doses of intravenous adenovirus vectors have been associated with development of thrombocytopenia of undetermined origin. Viral internalization requires the presence cell surface integrins, alpha(v)beta(3) or alpha(v)beta(5), that can blind ligands with a arginine-glycine-aspartic acid (RGD) sequence. This sequence is found in the adenovirus penton base. Platelets express the alpha(v)beta(3) integrin and other integrins that bind the RGD sequence of ligands such as fibrinogen, laminin, vitronectin, and von Willebrand factor (vWF). Platelet aggregation is mediated, in part, by the binding of the RGD sequence of fibrinogen to a platelet surface integrin, glycoprotein IIb/IIIa (GP IIb/IIIa). We investigated whether adenovirus particles could interfere with or potentiate agonist-induced platelet aggregation. Incubation of platelet-rich plasma with adenovirus under stirred conditions did not promote spontaneous aggregation. The addition of physiological platelet agonists, ADP, collagen, or epinephrine, induced platelet aggregation. However, the presence of adenovirus in a wide range of concentrations did not inhibit or potentiate agonist-induced aggregation. These results suggest that the adenovirus-associated thrombocytopenia observed in vivo is independent of a direct effect of the virus on platelet aggregation.     

Quality in Clinical Practice

This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference.     

Postoperative convalescence after inguinal hernia surgery: Prospective randomized multicenter study of laparoscopic versus Shouldice inguinal hernia repair in 1042 patients

Interest in inguinal hernia surgery has increased significantly with the introduction of new operating techniques during the past decade. This multicenter study compared short-term results in patients treated by the laparoscopic transabdominal preperitoneal patch technique (TAPP; n=518) and the Shouldice technique (n=524). We evaluated demographics, operative data, complications, hospital stay, postoperative pain, use of analgesics, functional status, sick leave, and complaints up to 3 months postoperatively. The median operating time was shorter in the Shouldice group (55 vs. 65 min), but there were no significant differences in complication rates, and major complications were rare. The hospital stay was 1 day or less in over 98% of cases in both groups, but more operations were performed on outpatient basis in the Shouldice group. In the TAPP group postoperative pain and analgesic consumption were less, postoperative functional status was better, and sick leave was shorter (10 vs. 14 days). These results show that the two methods are equally safe and have few major complications. The TAPP operation is associated with less postoperative pain, better postoperative functional status, and shorter sick leave, but at the price of a longer operating time. Electronic Publication     

Carcinogenicity of dextran sulfate sodium in relation to its molecular weight

The carcinogenicity of dextran and 3 kinds of dextran sulfate sodium with different molecular weights and almost the same sulfur content were compared in ACI rats. Dextran sulfate sodium of molecular weight 54,000 showed a strong carcinogenic activity when it was given orally as 2.5% diet, whereas dextran sulfate sodium of molecular weight 520,000 and 9500 and dextran showed no significant carcinogenicity, i.e. the peak of carcinogenic activity of dextran sulfate sodium appeared at molecular weight 54,000, and dextran sulfates with larger or smaller molecular weights had no carcinogenic activity.