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A key mystery of the DNA replication process has been unraveled by researchers from King Abdullah University of Science and Technology (KAUST).

Before a bacterium can divide, it must make a copy of its genetic material, the circular DNA molecules that resemble bunched rubber bands, through a process called DNA replication. In this process, the two strands of DNA making up the circular DNA molecule unwind and separate to become templates for generating new strands.

To ensure the process is well regulated, the bacterium has set a number of “roadblocks,” or termination sites on the DNA, to ensure the permanent stoppage of replication forks, Y-shaped structures formed between the strands as the DNA molecule splits.

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A UCSF-led team has developed a technique to build tiny models of human tissues, called organoids, more precisely than ever before using a process that turns human cells into a biological equivalent of LEGO bricks. These mini-tissues in a dish can be used to study how particular structural features of tissue affect normal growth or go awry in cancer. They could be used for therapeutic drug screening and to help teach researchers how to grow whole human organs.

The new technique — called DNA Programmed Assembly of Cells (DPAC) and reported in the journal Nature Methods on August 31, 2015 — allows researchers to create arrays of thousands of custom-designed organoids, such as models of human mammary glands containing several hundred cells each, which can be built in a matter of hours.

There are few limits to the tissues this technology can mimic, said Zev Gartner, PhD, the paper’s senior author and an associate professor of pharmaceutical chemistry at UCSF. “We can take any cell type we want and program just where it goes. We can precisely control who’s talking to whom and who’s touching whom at the earliest stages. The cells then follow these initially programmed spatial cues to interact, move around, and develop into tissues over time.”

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Engineers at the University of Toronto just made assembling functional heart tissue as easy as fastening your shoes. The team has created a biocompatible scaffold that allows sheets of beating heart cells to snap together just like Velcro™.

“One of the main advantages is the ease of use,” says biomedical engineer Professor Milica Radisic, who led the project. “We can build larger tissue structures immediately before they are needed, and disassemble them just as easily. I don’t know of any other technique that gives this ability.”

Growing heart muscle cells in the lab is nothing new. The problem is that too often, these cells don’t resemble those found in the body. Real heart cells grow in an environment replete with protein scaffolds and support cells that help shape them into long, lean beating machines. In contrast, lab-grown cells often lack these supports, and tend to be amorphous and weak. Radisic and her team focus on engineering artificial environments that more closely imitate what cells see in the body, resulting in tougher, more robust cells.

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Ice creams and hot summer days seem to go together perfectly, until you realise the heat of the latter is turning the former into a melting mass of deliciousness oozing down the side of your cone.

Luckily for us, scientists have discovered a naturally occurring protein that can be used in ice cream to make it more resistant to melting than the ice creams we enjoy today. According to researchers at the Universities of Edinburgh and Dundee in Scotland, the protein, which is called BslA, will allow ice cream to stay frozen for longer by binding together the air, fat and water in the product.

Not only will this make ice cream more impervious to things like heat, but the researchers say it also results in a super-smooth consistency. The protein, which can be made inside friendly bacteria, adheres to fat droplets and air bubbles, making for a more stable ice cream mixture that prevents the development of ice crystals.

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Oh great, now republicans can start bitching about same sex robotic marriage! lol! At least it’ll give them something to do after they are booted out of office.

I always try to look on the bright side. wink


(credit: AMC)

The Supreme Court’s recent 5–4 decision in Obergefell v. Hodges legalizing same-sex marriage raises the interesting question: what’s next on the “slippery slope”? Robot-human marriages? Robot-robot marriages?

Why yes, predicts on Slate.

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