Science and Medicine

New Device for Identifying Aggressive Breast Cancers



A new disposable device based on advances in microfluidics may help identify advanced breast cancer patients who are candidates for therapy with the drug trastuzumab (Herceptin). The device is described in the American Institute of Physics’ journal Biomicrofluidics.

Aggressive breast cancers with poor prognosis typically have abnormal levels of the protein HER2 (the tyrosine kinase human epidermal growth factor receptor 2). The new elastomeric, rubber-like device is designed to efficiently capture cancer cells overexpressing HER2 in circulating blood.

Finding a way to identify these cells is medically relevant because HER2 positive patients with early breast cancer have been found to significantly benefit from treatment with Herceptin or trastuzumab, the humanized monoclonal antibody against HER2, which can lower recurrence risk by about half. Given the cost ($50,000 - $65,000 per year in the United States) and possible side effects of Herceptin therapy, establishing HER2 status is crucial.

Current methodologies for determining HER2 status include immunohistochemistry and fluorescence in situ hybridization (FISH), both of which require biopsies. But biopsy-based testing may lead to ineffective treatment choices because in about 20% of breast cancers, the HER2 status of the primary tumor may differ from that of a metastatic tumor. This fact has made the noninvasive alternative of profiling circulating tumor cells a long-sought but elusive goal. Isolating circulating tumor cells, which are present at ratios as low as 1 to 10 per billion blood cells, is extremely challenging.

Recently, interest in microfluidic devices for capturing circulating tumor cells (CTCs) has intensified because of their greatly improved capabilities. A microfabricated device developed by researchers at the Massachusetts General Hospital and designed to bind to cells of epithelial origins (most cancers originate from epithelial tissues) circulating in the blood demonstrated near-perfect ability to isolate circulating tumor cells across a range of cancers.

In a study supported by the National Health and Medical Research Council Australia, Benjamin Thierry and colleagues at the Ian Wark Research Institute at the University of South Australia developed a plastic-based disposable microfluidic device offering several improvements for capturing circulating tumor cells. The device is designed to take advantage of the features of an organic silicone found in contact lenses and shampoos called polydimethylsiloxane (PDMS), which is compatible with soft molding techniques, transparent, and permeable to gasses.

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Stonehenge Boy was from the Mediterranean



The boy was buried with around 90 amber beads. Chemical tests on teeth from an ancient burial near Stonehenge indicate that the person in the grave grew up around the Mediterranean Sea.

The bones belong to a teenager who died 3,550 years ago and was buried with a distinctive amber necklace.

The conclusions come from analysis of different forms of the elements oxygen and strontium in his tooth enamel.

Analysis on a previous skeleton found near Stonehenge showed that that person was also a migrant to the area.

The findings will be discussed at a science symposium in London to mark the 175th anniversary of the British Geological Survey (BGS).

The “Boy with the Amber Necklace,” as he is known to archaeologists, was found in 2005, about 5 km southeast of Stonehenge on Boscombe Down.

The remains of the teenager were discovered next to a Bronze Age burial mound during roadwork for military housing.

“He’s around 14 or 15 years old and he’s buried with this beautiful necklace,” said Professor Jane Evans, head of archaeological science for the BGS. “The position of his burial, the fact he’s near Stonehenge, and the necklace all suggest he’s of significant status.”

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Gulf Oil Spill’s Vastness Confirmed: Largest Marine Oil Accident Ever



The researchers used high-resolution video clips of flow from the Deepwater Horizon well to measure volume. (Credit: Courtesy US Senate Committee on Environment and Public Works)

BP’s leaking oil well in the Gulf of Mexico was conclusively sealed this week, but even now, questions remain about the amount of oil that actually came out of it. Initially after the April 20 explosion, officials claimed that the flow could not be measured. Then, as public pressure for information mounted, they looked for ways to measure it, and started producing estimates: at first, 1,000 barrels a day; then 5,000; then 12,000 to 19,000; then upward from there. Now, in the first independent, peer-reviewed paper on the leak’s volume, scientists have affirmed heightened estimates of what is now acknowledged as the largest marine oil accident ever.

Using a new technique to analyze underwater video of the well riser, they say it leaked some 56,000 to 68,000 barrels daily—maybe more—until the first effective cap was installed on July 15. Their estimate of the total oil escaped into the open ocean is some 4.4 million barrels—close to the most recent consensus of government advisors, whose methods have not been detailed publicly.

The paper appears in this week’s early online edition of the journal Science.

“We wanted to do an independent estimate because people had the sense that the numbers out there were not necessarily accurate,” said lead author Timothy Crone, a marine geophysicist at Columbia University’s Lamont-Doherty Earth Observatory. After BP and government officials downplayed the possibility or importance of measurements, a wide spectrum of scientists, environmental groups and legal experts pointed out that the information was needed to determine both short- and long-term responses, and monetary liability.

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