Fifty-one Japanese professional surfers were examined in order to analyze surfer's ear. Forty-one cases (80%), 71 ears, were diagnosed as surfer's ear. In 19 cases (37%), 30 ears, the external auditory canals had stenosed by more than 50%. In general, surfer's ear begins to appear after 5 years and is further aggravated by continued surfing. The age at which surfing is taken up has no influence on the appearance of surfer's ear. Surfers who surf on northern (colder) coasts have severer surfer's ear than those who frequent the southern (warmer) coasts.

Cholesterol biosynthesis is a high-cost process and, therefore, tightly regulated by both transcriptional and posttranslational negative feedback mechanisms in response to the level of cellular cholesterol. Squalene monooxygenase (SM, also known as squalene epoxidase or SQLE) is a rate-limiting enzyme in the cholesterol biosynthetic pathway and catalyzes epoxidation of squalene. The stability of SM is negatively regulated by cholesterol via its N-terminal regulatory domain (SM-N100). In this study, using a SM-luciferase fusion reporter cell line, we performed a chemical genetics screen that identified inhibitors of SM itself as up-regulators of SM. This effect was mediated through the SM-N100 region, competed with cholesterol-accelerated degradation, and required the E3 ubiquitin ligase MARCH6. However, up-regulation was not observed with statins, well-established cholesterol biosynthesis inhibitors, and this pointed to the presence of another mechanism other than reduced cholesterol synthesis. Further analyses revealed that squalene accumulation upon treatment with the SM inhibitor was responsible for the up-regulatory effect. Using photoaffinity labeling, we demonstrated that squalene directly bound to the N100 region, thereby reducing interaction with and ubiquitination by MARCH6. Our findings suggest that SM senses squalene via its N100 domain to increase its metabolic capacity, highlighting squalene as a feedforward factor for the cholesterol biosynthetic pathway.

Multifidene and Aucantene, Cl1 Hydrocarbons in the Male-Attracting Essential Oil from the Gynogametes of Cutleria multij?da (Smith) Grev. (Phaeophyta) Sir :Cellular chemotaxis plays a role in the reproduction of brown algae (Phaeophyta); Le., the gynogametes (eggs) release volatile substances that act as attractants for the androgametes (sperm). In the isogamous seaweed Ectocarpus siliculosus, for example, the sex attractant has been identified as (6S)-(cis-l '-buteny1)-1,C cycloheptadiene (ectocarpene, 4), a compound which is also a constituent of the essential oils from vegetative thalli of Dictyopteris plagiogramma and D . australis. 3, In the oogamous seaweed Fucus serratus the male attractant is a 1,3,5-octatriene (f~coserratene).~ In this communication we wish to report the isolation and structure determination of the male-attracting substance and a related, biologically inactive compound (6) Male gametes were exposed to vaseline droplets containing the samples. The halo of gametes around such lures, measured against blanks, is indicative of gamone activity: D. G. Miiller, Biochem.Physiol. PP., in press.

The potent antifungal constituent against Pyricularia oryzae Cav. obtained from Podophyllum peltatum L. has been disclosed to be a mixture of three new 3-acyl-4-hydroxy-5,6-dihydropyrones (podiblastin A, B and C). The absolute configuration at C-6 of podoblastins was determined to be (R).

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