Could the elongate yellow-orange nostrils of Anguilla bicolor McClelland, 1844 function as fishing lures?

The shortfin eel Anguilla bicolor has elongate, yellow nostrils tipped with orange that protrude forward above the mouth. They are a striking, highly visible feature and it is hypothesised that they function as lures to attract prey, analogous to the illicium and esca of anglerfishes and frogfishes and the lingual appendage of the alligator snapping turtle. Another possible function is as an intraspecific signalling device. The first hypothesis is favoured here.     

BRCA1 and BRCA2 associated breast cancer and the roles of current modelling systems in drug discovery

For a drug candidate to be fully developed takes years and investment of hundreds of millions of dollars. There is no doubt that drug development is difficult and risky, but vital to protecting against devastating disease. This difficulty is clearly evident in BRCA1 and BRCA2 related breast cancer, with current treatment options largely confined to invasive surgical procedures, as well as chemotherapy and radiotherapy regimes which damage healthy tissue and can leave remnant disease. Consequently, patient survival and relapse rates are far from ideal, and new candidate treatments are needed. The preclinical stages of drug discovery are crucial to get right for translation to hospital beds. Disease models must take advantage of current technologies and be accurate for rapid and translatable treatments. Careful selection of cell lines must be coupled with high throughput techniques, with promising results trialled further in highly accurate humanised patient derived xenograft models. Traditional adherent drug screening should transition to 3D culture systems amenable to high throughput techniques if the gap between in vitro and in vivo studies is to be partially bridged. The possibility of organoid, induced pluripotent stem cell, and conditionally reprogrammed in vitro models is tantalising, however protocols are yet to be fully established. This review of BRCA1 and BRCA2 cancer biology and current modelling systems will hopefully guide the design of future drug discovery endeavours and highlight areas requiring improvement.     

Successful maintenance of suckling rat ileum in organ culture.

Ileum from rats 4, 9, 11, 12, and 15 days old can best be maintained for 24 hours in a system using Hanks' Balanced Salt Solution without fetal calf serum, at 25 degrees C and 21% O2. Suckling rat duodenum and jejunum were difficult to maintain well for 24 hours in this system or a variety of other systems that were tried. A temperature of 37 degrees C hastened deterioration of duodenum, jejunum or ileum. With ileum, 3H-thymidine and 14C-leucine were increasingly incorporated into DNA and protein over the 24-hour period. Light microscopy, as well as scanning and transmission electron microscopy, showed very good preservation of the ileum after 24 hours. The addition to the medium of hydrocortisone, 1 micron, and thyroxine, 0.01 micron, alone or in combination, did not change DNA or protein synthesis, or morphology, possibly because of the relatively short (24 hour) time period. Our organ culture system emphasizes the differences between suckling rat ileum and the rest of the intestine, and provides a new tool for evaluating, over a 24-hour period, the developing rat small intestine.     

Regulation of methanol and methylamine dehydrogenases in Methylophilus methylotrophus

Abstract Methylophilus methylotrophus can use methylamine as sole source of carbon and nitrogen. Measurements of the specific activity of methylamine dehydrogenase (MNDH) in bacteria grown in batch or chemostat culture showed that MNDH was induced by methylamine and repressed when methanol or NH₄⁺ were provided as alternative carbon or nitrogen sources. The degree of repression varied with the growth conditions. Methanol dehydrogenase (MDH) was present in bacteria growtn on methylamine as sole carbon source, but the specific activity was low compared with that in bacteria grown on medium containing methanol, indicating that this enzyme is induced by methanol.