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The synthesis of the antifungal dilactones, UK-2A and UK-3A, is described. In addition to providing a workable synthetic route to these potent antifungal antibiotics, this has allowed us to determine the assignment of the relative and absolute configurations in the nine-membered ring. Furthermore, UK-2A analogs were also synthesized and evaluated their antifungal activities and cytotoxic activities along with UK-2A, (2R, 3R, 4S, 7R)-UK-2A, UK-3A, (2R, 3R, 4S, 7R)-UK-3A, and antimycin A. The structural requirements for the selective cytotoxicity against yeasts and filamentous fungi will also be suggested.

We describe a case of coronary spasm in a 59-year-old man undergoing an emergent abdominal aortic replacement for ruptured aortic aneurysm. The patient was brought to the operating room in a state of hypovolemic shock, and was successfully resuscitated through intensive volume expansion by rapid infusion devices. Twenty minutes after cross-clamping of the abdominal aorta, ST-segment elevation on the lead III of electrocardiogram (ECG) and dyskinesis in the inferior wall shown by transesophageal echocardiography (TEE) were noted. Coronary spasm was suspected, and isosorbide dinitrate was administered intravenously without delay, leading to prompt reversal of ischemic changes. A number of reports have suggested that care should be taken against coronary spasm in non-cardiac surgery as well as cardiac surgery, especially in patients with coronary risk factors. Monitoring by multi-lead ECG and TEE is a powerful method by which to detect and evaluate intraoperative myocardial ischemia.

Overproduction of the Pseudomonas aeruginosa outer membrane protein OprM was observed in the nalidixix acid (NalB-type) multidrug-resistant strains. To clarify the involvement of OprM in the resistance, transposon mutants were isolated from strain PAO4141 and its OprM-overexpressed mutant KG2113 and were screened for OprM production by immunoblot assays using murine polyclonal antiserum resulting from immunization with purified OprM. Two OprM-deficient mutants from PAO4141 and one from KG2113 were identified. Determination of the susceptibilities of these mutants to antimicrobial agents demonstrated that OprM was involved not only in the acquired resistance, but also in the intrinsic resistance of P. aeruginosa to quinolones, cephems, penicillins, tetracycline, and chloramphenicol.

OprM with a M(r) of 49 K is associated with the multidrug resistance of Pseudomonas aeruginosa. Detergent fractionation of bacterial cells has demonstrated that OprM is located in the outer membrane from which it sediments with the other major outer membrane proteins. In this study we have determined the location of OprM as the P. aeruginosa outer membrane. Western immunoblots of cell fractions, obtained by sucrose density gradient centrifugation of whole cell lysates, were probed with an OprM-specific murine polyclonal antiserum.

The UV-irradiation of 2- and 4-pyridinecarboxamides in alcohol brings about alkylation and/or hydroxyalkylation in the pyridine ring. In the irradiation of 3-pyridinecarboxamide in the presence of sulfuric acid, ionic reaction (alkoxylation at the 2- and 6-position) and radical reaction (alkylation at the 4- and 6-position) occur in parallel. The effects of quenchers indicate that two alkylation products originate from one excited triplet state which is quenched by energy-transfer mechanism and that two alkoxylation products originate from the excited singlet state.