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Plums Poised To Give Blueberries Run For The Money

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There’s an emerging star in the super-food world. Plums are rolling down the food fashion runway sporting newly discovered high levels of healthy nutrients, say scientists at Texas AgriLife Research.Plainly, “blueberries have some stiff competition,” said Dr. Luis Cisneros, AgriLife Research food scientist."Stone fruits are super fruits with plums as emerging stars."

Far from fruit snobbery, the plum is being ushered in after Cisneros and Dr. David Byrne, AgriLife Research plant breeder, judged more than 100 varieties of plums, peaches and nectarines and found them to match or exceed the much-touted blueberries in antioxidants and phytonutrients associated with disease prevention.

The duo acknowledge that blueberries remain a good nutritional choice. But Byrne said their findings are plum good news, especially in tight economic times, because one relatively inexpensive plum contains about the same amount of antioxidants as a handful of more expensive blueberries.

“People tend to eat just a few blueberries at a time – a few on the cereal or as an ingredient mixed with lots of sugar,” Cisneros said. “But people will eat a whole plum at once and get the full benefit.”

Discovery of the plum’s benefits – along with that of fellow stone fruits, the peach and the nectarine – came after the researchers measured at least five brands of blueberries on the market. Against those numbers, the team measured the content of more than 100 different types of plums, nectarines and peaches.

The first comparison was for antioxidants, molecules that sweep through a body looking for free radicals to knock out. Free radicals are atoms or molecules that lurk where diseases like cancer and heart disease are found.

"If the radicals aren’t taken care of,” Cisneros said, “they will cause the problems that lead to disease.”

But the scientists didn’t stop at knowing that plums and peaches were flexing their antioxidant muscles.

“Knowing that we had all these varieties with high levels of antioxidants, then the possibility of preventing these diseases would also be high with their consumption, so we went to the next step – how these compounds could actually inhibit chronic diseases,” Cisneros said.

The team examined the full content of plums and peaches, then tested the effect of the compounds they found on breast cancer cells and cholesterol in the lab.

“We screened the varieties again with the biological assays,” Cisneros said. “And that had never been done before, because it is expensive and a lot of work. But that investment is small in terms of the information we got, and how it can be used now for breeding efforts to produce even better fruit.”

Byrne noted, for example, that one benefit the team found was that the phytonutrients in plums inhibited in vitro breast cancer growth without adversely affecting normal cell growth.

He said this type of research needs further study but is an indication that breeders ultimately will be able to produce new crop varieties with the best ratio of various phytochemicals to have an impact on disease prevention and inhibition. And these fruits will be available as fresh produce as well as in extracts for dietary supplements.

"Future work with stone fruits will focus on cardiovascular and cancer using animal models and identification of specific compounds that exert the properties," Cisneros added.

Bottom line from the researchers: “We suggest that consumers take seriously the recommendation to eat at least five servings of fruits and vegetables – or even more – every day and to make sure that plums are part of that,” Byrne said.

Funding comes from the Vegetable and Fruit Improvement Center at Texas A&M University and the California Tree Fruit Agreement.

Surgeons Use Microwave Technology To Destroy Tumors

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A new minimally-invasive option for treating liver tumors, called microwave ablation, is now available at UC San Diego Medical Center and Moores UCSD Cancer Center, the only hospitals in the region to offer this technology to patients.“A liver tumor can be removed in many ways,” said Marquis Hart, MD, transplant surgeon at UC San Diego Medical Center. “Now, patients at UC San Diego have a new option called ‘microwave ablation.’ Simply put, we zap and destroy liver tumors with heat derived from microwave energy. This is an important alternative, especially since the majority of liver cancers cannot be partially removed and not all patients are transplant candidates.”

Liver cancer is on the rise in the United States, linked closely with the epidemic of hepatitis and other conditions causing cirrhosis, a degenerative disease of the liver. Current treatment options for liver cancer include transplantation, partial surgical removal of the liver, chemotherapy, radiation, or ablation—the destruction of abnormal tissue with heat from radiofrequency waves, high frequency ultrasound, freezing, or alcohol injection. Now, microwave technology, offered by Covidien, removes the tumor with intense heat.

To perform the procedure, Hart accesses the tumor through the skin, or through a small laparoscopic port or open incision. With ultrasound guidance or a computed tomography (CT) scan, the tumor is located and then pierced with a thin antenna which emits microwaves. This energy spins the water molecules in the tumor producing friction which causes heat. Temperatures above 60 degrees Celsius (140 degrees Fahrenheit) cause cellular death, usually within 10 minutes.

“Microwave ablation causes the tumor to be quickly and precisely removed. If necessary, multiple tumors can be treated at the same time,” said Hart. “This method appears to be more efficient than other ablation techniques which translates to better tumor destruction and less time for the patient under general anesthesia.”

In addition to liver disease, microwave ablation has promising potential in the treatment of lung, kidney, and bone cancer.

“The incidence of liver cancer in the United States has more than doubled in the last 20 years,” said Hart. “Conditions that cause chronic liver damage increase the risk of liver cancer. Fortunately the treatment options at UC San Diego Medical Center and Moores UCSD Cancer Center are numerous. No where else in the region will you find a multidisciplinary team of surgeons, hepatologists, radiologists, and oncologists offering the latest in cancer care. With a team dedicated specifically to the liver, our patients receive cutting–edge care from a diverse team of experts.”

According to the National Cancer Institute, primary liver and bile duct cancers are the fifth most common cause of cancer death in men and the ninth most common cause of cancer death in women. More than 90 percent of all cases occur in men and women age 45 or older. Liver cancer is closely associated with hepatitis virus infections. The incidence and mortality rates for these cancers have increased in all races and both sexes in the past two decades.

Single Gene Lets Bacteria Jump From Host To Host

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All life — plants, animals, people — depends on peaceful coexistence with a swarm of microbial life that performs vital services from helping to convert food to energy to protection from disease.Now, with the help of a squid that uses a luminescent bacterium to create a predator-fooling light organ and a fish that uses a different strain of the same species of bacteria like a flashlight to illuminate the dark nooks of the reefs where it lives, scientists have found that gaining a single gene is enough for the microbe to switch host animals.

The finding, reported this week (Feb. 1) in the journal Nature by a team of scientists from the University of Wisconsin-Madison, is important not only because it peels back some of the mystery of how bacteria evolved to colonize different animals, but also because it reveals a genetic pressure point that could be manipulated to thwart the germs that make us sick.

"It seems that every animal we know about has microbes associated with it," says Mark J. Mandel, the lead author of the study and a postdoctoral fellow in the UW-Madison School of Medicine and Public Health. "We pick up our microbial partners from the environment and they provide us with a raft of services from helping digestion to protection from disease."

In the Pacific, a species of bacteria known as Vibrio fischeri lives in luminescent harmony with two distinct hosts: the diminutive nocturnal bobtail squid and the reef-dwelling pinecone fish. In the squid, which feeds at night near the ocean surface, one strain of the bacterium forms a light organ that mimics moonlight and acts like a cloaking device to shield the squid from hungry predators below. In the pinecone fish, another strain of the bacterium colonizes a light organ within the animal's jaw and helps illuminate the dark reefs in which it forages at night. The fish light organ may also play a role in attracting the zooplankton that make up the pinecone fish's menu.

But how did a single species of bacteria come to terms with such different hosts?

Working in the UW-Madison laboratory of microbiologist Ned Ruby, Mandel and his colleagues scoured the genomes of the two different strains of V. fischeri and found that most of the bacterium's genetic architecture was conserved over the course of millions of years of evolutionary history, but with a key difference: The strain that colonizes the squid has a regulatory gene that controls other genes that lay down a biofilm that allows the microbe to colonize the animal's light organ.

"During squid colonization, this regulatory gene turns on a suite of genes that allow bacteria to colonize the squid through mucus produced by the animal," Mandel explains. "The mucus is the pathway to the light organ, but it also helps keep out the bad guys."

Both strains of bacteria, Mandel explains, have the same genes that produce the biofilms the bacterium needs to get established in its host. But the regulatory gene that sets the other biofilm genes in motion is absent in the strain that lives in the pinecone fish, the animal scientists believe was first colonized by V. fischeri before it moved in to the squid light organ when the squid family came onto the scene in the Pacific Ocean at least 30 million years ago.

"The regulatory gene entered the bacterium's lineage and allowed it to expand its host range into the squid," according to Mandel. "The bottom-line message of the paper is that bacteria can shift host range by modifying their capabilities with small regulatory changes."

The regulatory gene acquired by the bacterium, notes Ruby, is essentially a switch the organism uses to activate a set of genes that had been residing quietly in the V. fischeri genome. Such mechanisms, he says, are very likely at play in many other species of bacteria, including those that infect humans and cause illness.

"This is going to inform a question that has been around a long time in the area of pathogenesis," says Ruby. One line of thought is that "in order to become a pathogen, a whole suite of genes needs to be imported to a bacterium."

The new finding by his group, however, suggests that nature is far more parsimonious: Instead of requiring organisms to acquire many new genes to occupy a new host, the combination of a new regulatory gene and genes that already reside in a bacterium is enough to do the trick.

"Together, they can do something neither of them could do before. They can mix and match and open up new niches," says Ruby.

Knowing that a regulatory gene plays a key role in allowing an organism to fit a new host may prove useful in human medicine as many bacterial pathogens arose first in other animals before infecting humans. A single gene can be a much easier target for a drug or other intervention to prevent or mitigate infection, the Wisconsin scientists say.

In addition to Ruby and Mandel, authors of the new Nature report include Michael S. Wollenberg, also of UW-Madison; Eric V. Stabb of the University of Georgia; and Karen L. Visick of Loyola University Chicago. The study was supported by grants from the Betty and Gordon Moore Foundation, the National Institutes of Health and the National Science Foundation.