Lake

Lake Vostok, the 7^th largest (by volume) and 4^th deepest lake on Earth, is covered by more than 3,700 m of ice, making it the largest subglacial lake known. The combination of cold, heat (from possible hydrothermal activity), pressure (from the overriding glacier), limited nutrients and complete darkness presents extreme challenges to life. Here, we report metagenomic/metatranscriptomic sequence analyses from four accretion ice sections from the Vostok 5G ice core. Two sections accreted in the vicinity of an embayment on the southwestern end of the lake, and the other two represented part of the southern main basin. We obtained 3,507 unique gene sequences from concentrates of 500 ml of 0.22 µm-filtered accretion ice meltwater. Taxonomic classifications (to genus and/or species) were possible for 1,623 of the sequences. Species determinations in combination with mRNA gene sequence results allowed deduction of the metabolic pathways represented in the accretion ice and, by extension, in the lake. Approximately 94% of the sequences were from Bacteria and 6% were from Eukarya. Only two sequences were from Archaea. In general, the taxa were similar to organisms previously described from lakes, brackish water, marine environments, soil, glaciers, ice, lake sediments, deep-sea sediments, deep-sea thermal vents, animals and plants. Sequences from aerobic, anaerobic, psychrophilic, thermophilic, halophilic, alkaliphilic, acidophilic, desiccation-resistant, autotrophic and heterotrophic organisms were present, including a number from multicellular eukaryotes.

Source and more infohttp://bit.ly/180fc3n

Liver

Liver cells derived from human induced pluripotent stem cells (iPSCs) and cultured with developmentally important progenitor cells self-organize into functional, three-dimensional liver buds, according to new research published today (July 3) in Nature. The liver buds exhibited metabolisms that, in some aspects, resembled that of human livers, the researchers found, and when transplanted into mice, the buds connected with the host circulatory system.

“I think the quality of the work in the paper is very high,” said Stephen Duncan, the director of the Regenerative Medicine Center at the Medical College of Wisconsin, who did not participate in the research. “They got iPSCs to differentiate by adding cells that produce the right growth factors . . . and then the cells spontaneously formed these three-dimensional aggregates that were able to form a rudimentary vasculature.”

There are currently more than 100,000 people around the globe with end-stage organ failure awaiting organ transplants. With no end to the shortage of organ donors in sight, scientists have for decades attempted to build organs for transplantation from the ground up. The discovery of embryonic stem cells in 1981 offered promise that custom-made organs could be grown in the lab. Later, the discovery of iPSCs offered the possibility of making organs from patient’s own undifferentiated cells, which would circumvent compatibility concerns.

“If you could use iPSCs to generate a truly functioning organ, then you would have this unlimited suitcase of spare parts that would be genetically matched to individuals,” said Duncan.

“Most researchers working on generating organs focus on one component: functional cell differentiation from human iPSCs,” said study lead Takanori Takebe, a regenerative medicine specialist at the Yokohama City University in Japan. “But that is not an efficient approach, so we established a new concept for three-dimensional organ generation.”

During natural liver development, sheets of liver cells cleave off of gut endodermal cells—the cells that make up the innermost germ cell layer of the embryo—and form a liver bud, a mass of condensed tissue that quickly becomes vascularized. To recapitulate liver development, Takebe’s team cultured the human hepatocytes, or liver cells, derived from iPSCs with two other developmentally important cell types—human umbilical vein endothelial cells and human mesenchymal stem cells. Within 48 hours of combining these three cell types, the mass of liver cells self-organized into three-dimensional clusters and formed blood vessels.

more info on:http://bit.ly/12PcUyv

shark

Another look at the goblin shark (Mitsukurina owstoni), a deep sea creature that's been sighted less that fifty times since its discovery. They're the only living representative of the family Mitsukurinidae.

This week in science

More info

Lake Vostok: http://bit.ly/180fc3n

Hawkmoths: http://bit.ly/17KgNu5

Liver: http://bit.ly/12PcUyv

HIV: http://bit.ly/12dzqFW

Radio waves: http://ars.to/18GyQEH

3D printed cast: http://bit.ly/154Byya

Turtles!!

Google science fair

A 15-year-old Victoria student is a finalist in Google's global science fair for building a battery-free flashlight powered by the heat of her hands.

Ann Makosinski will be flying to Mountain View, Calif., to present her science project, which is competing with 14 others for the top prize.

Makosinski said her project came from an interest in harvesting humans' untapped thermal energy.

The winner will be announced on Sept. 23 and receive a 10-day trip to the Galapagos Islands with National Geographic Expeditions, a $50,000 scholarship, and other prizes.

This week

sorry internet was down for a while.
Won't be as active for the next month.