What's the buzz

New technique makes spinach safer

University of Illinois scientists have found a way to reduce the number of E. coli 0157:H7 cells that may live undetected on spinach leaves.

“By combining continuous ultrasound treatment with chlorine washing, we can reduce the total number of foodborne pathogenic bacteria by over 99.99 percent,” said Hao Feng, a U of I professor of food science and human nutrition. According to Feng, the USDA is looking for proposed technologies that can achieve a 4 to 6 log reduction in pathogen cells (a 6 log reduction would achieve a million-fold reduction in pathogenic bacteria). The food processing industry can now achieve a 1 log or tenfold reduction. In comparison, the U of I technique yields a 4 log reduction. “Combining technologies is the key to bridging the gap between our current capacity and what USDA would like to see. The use of ultrasound exposure during chlorine washing gives the industry a way to significantly enhance microbial safety,” he said.

Feng’s pilot-scale system uses three pairs of large-area ultrasonic transducer boxes to form a channel through which ultrasound is provided to spinach leaves that are undergoing a continuous-flow chlorine wash. Spatial uniformity of ultrasound distribution was confirmed by tests using metallic foil. The scientist said that continuous flow and uniformity of the field are key elements in the success of the process.

“Placement of the produce as it makes its way through the channel turns out to be very important. We had to find ways to make sure that leaves received similar exposure to ultrasound, taking care to minimize the chance that one leaf would block a nearby leaf’s exposure to the sound waves,” he said.

Protein injection promising for muscular dystrophy

Injecting a novel human protein into muscle affected by Duchenne muscular dystrophy significantly increases its size and strength, scientists have discovered. The findings could lead to a therapy akin to the use of insulin by diabetics.

The study was conducted by Dr. Julia von Maltzahn and Dr. Michael Rudnicki, the Ottawascientist who discovered muscle stem cells in adults. “This is an unprecedented and dramatic restoration in muscle strength,” said Dr. Rudnicki, a senior scientist and director for the Regenerative Medicine Program and Sprott Centre for Stem Cell Research at the Ottawa Hospital Research Institute.

He is also a Canada Research Chair in Molecular Genetics and professor in the Faculty of Medicine at the University of Ottawa.

“We know from our previous work that this protein, called Wnt7a, promotes the growth and repair of healthy muscle tissue. In this study we show the same types of improvement in a mouse model of Duchenne muscular dystrophy. We found that Wnt7a injections increased muscle strength almost two-fold, to nearly normal levels. We also found that the size of the muscle fibre increased and there was less muscle damage, compared to mice not given Wnt7a,” he explained.

“This is also exciting because we think it’s a therapeutic approach that could apply to other muscle-wasting diseases,” said Dr. Rudnicki.

Mass of gigantic black hole measured

Using the Hobby-Eberly Telescope at The University of Texas at Austin’s McDonald Observatory, astronomers have measured the mass of what may be the most massive black hole yet — 17 billion Suns — in galaxy NGC 1277.

The unusual black hole makes up 14 per cent of its galaxy’s mass, rather than the usual 0.1 percent.  This galaxy and several more in the same study could change theories of how black holes and galaxies form and evolve. NGC 1277 lies 220 million light-years away in the constellation Perseus. The galaxy is only ten percent the size and mass of our own Milky Way. Despite NGC 1277’s diminutive size, the black hole at its heart is more than 11 times as wide as Neptune’s orbit around the Sun.

“This is a really oddball galaxy. It’s almost all black hole. This could be the first object in a new class of galaxy-black hole systems,” said team member Karl Gebhardt of The University of Texas at Austin.

 The study’s endgame is to better understand how black holes and galaxies form and grow together, a process that isn’t well understood.

DH Newsletter Privacy Policy Get top news in your inbox daily
GET IT
Comments (+)