Tests could determine source of ‘mystery tumors‘

New tests may hold the key to identifying and treating unidentified cancerous tumors.

Tumors of unknown origin account for at least 30,000 new cancer cases each year, making them more numerous than brain, liver or stomach cancers. These mystery tumors are extremely dangerous, as cancer is treated based on the originating location of the tumor regardless of where it has spread.

Four new tests on the market are able to determine which genes are active or inactive in a sample of the tumor by analyzing its genetic fingerprint and comparing it to known tumor types. The test costs approximately $3,000. The Food and Drug Administration has only approved one version of the test so far, but laboratories can offer the others even without FDA approval.

Critics of the test maintain that studies that put the tests‘ accuracy at 80 to 90 percent are misleading because those numbers only occur when testing known tumors. Accuracy in testing mystery tumors is closer to 64 percent, they say.

(Source: nytimes.com)

No special spot in the brain for religious feelings

Scientists at the National Institute of Neurological Disorders and Stroke have concluded that there is no specific region or network in the brain for religious thoughts or feelings.

When researchers questioned subjects about their religious beliefs while monitoring the blood flow of the brain, they found that neural activity occurred in areas already known to have other nonreligious functions. Examples include the theory of mind networks that predict other people’s intentions.

Critics doubt that biological functions, like those measured in this study, can capture all of what religion truly is. One scientist’s research has found that certain areas of the brain enlarge after prolonged meditation.

(Source: nytimes.com)

Obama to uphold Bush decision to de-list gray wolves

President Barack Obama’s interior secretary Ken Salazar announced on Friday that the administration agrees with former President Bush’s last-minute removal of the gray wolf from the endangered species list.

The wolves, which have a population of approximately 5,600 nationwide, are no longer classified as endangered in the Northern Rockies and the western Great Lakes. The predator will remain on the list in Wyoming, as the state’s wolf recovery plan has been insufficient, Salazar said.

Environmental groups previously sued successfully to get the gray wolf put back on the list after the Bush administration initially removed it. They will most likely sue again to retain federal protection for the species.

(Source: sfgate.com)

ALYSOUN BONDE compiles SCIENCE SCENE. She can be reached at campus@theaggie.org. XXX

A recent study by UC Davis researchers showed that declining populations of sea otters could be attributed to pathogens in their diet.

Such pathogens are also influencing their behavior on the sea floor, slowing their biologically inclined recovery times – the time it takes an otter to come up to shore. Conditions such as brain disease are becoming more prevalent and a strong link has been found to their nutrition intake.

Sea otters have been a threatened species for a number of years and their populations have been hitting record lows. Christine Johnson, the lead author of the study and a veterinary epidemiologist at the UC Davis Wildlife Health Center, conducted the research in hopes of gaining insight into their deterioration and how it could be fixed.

“Sea otters are important because they are a keystone species for the near shore ecosystems,” Johnson said, explaining that sea otters play an important role in the biological concept of biodiversity.

“Our study was prompted by two observations. First, we have found over the past decade that sea otters have been suffering high levels of mortality from infectious disease, and we suspected that many of these diseases were transferred to the otters via their prey. Secondly, we had discovered that sea otters exhibited high levels of individual variation in diet, and that this tendency seemed to be linked to food abundances,” said Tim Tinker, a co-researcher in the study and assistant research biologist at UC Santa Cruz.

This led the researchers to examine two key factors that limit sea otter population growth: disease and resource limitation.

One disease sea otters are inflicted with is brain infections caused by ingesting toxins. There are two bacteria that increase the risks of brain infection – Toxoplasma gondii and Sarcocystis neurona.

“Both pathogens cause brain disease in otters and cause mortality – we were curious to see why some sea otters were getting exposed to these pathogens and others weren’t,” Johnson said.

These two bacteria seem to be prevalent in the sea otter diet. The study showed that sea otters are having difficulty obtaining adequate nutrition and therefore settled on eating things that lack any nutritional content.

Sea otter diet is the best when they can feed on abalone. This preferred diet has, however, proven to be more difficult to obtain and thus the otters have been resorting to feeding on marine snails, clams and small crabs. This novel diet contains T. gondii strains and S. neurona strains depending on which region the sea otters are living in.

Depending on the habitat that the sea otters lived in, the bacteria was more prevalent. Sea otters living near San Francisco’s Fisherman’s Wharf and Monterey’s Cannery Row were more susceptible to S. neurona bacterial strains. Those living along the Central California coast near San Simeon and Cambria were prone to T. gondii strains.

The study’s implications consist of trying to regenerate abalone and trying to train sea otters to stray from their dangerous diet. Researchers aim to discover how the diet can be readjusted and save the food web.

SADAF MOGHIMI can be reached at features@theaggie.org.

In cooperation with federal, state and county agencies, UC Davis has taken drastic action to safeguard the university’s ongoing rice research and California’s rice industry by ridding its greenhouses of a new and destructive pest – the panicle rice mite.

The microscopic mites, which are not native to the U.S., infested breeding facility greenhouses and rice fields in Arkansas, Louisiana, Texas and New York during the summer of 2007. The latest infestation was discovered in 11 UC Davis campus greenhouses in January this year, and is the first reported case in California and the western U.S.

The mites feed on developing rice grains and leaf sheaths on rice plants, and transmit fungal diseases that cause blight. They can spread by hitching on clothing, equipment or rice seeds, and have reportedly caused major damage to rice crops in other countries where they have been found.

Although the tropical exotic mites are unlikely to gain a stronghold in the Sacramento Valley’s dry climate, the university is not taking any chances to let the pest slip into the state’s estimated 550,000 acres of rice fields near Sacramento, which are valued at close to $1 million in terms of farm gain value, said Michael Parrella, an entomology professor and associate dean of agricultural sciences in the College of Agricultural and Environmental Sciences.

“[The infestation] appears to be confined to the greenhouses, and my hope is that we have eliminated the mite from those greenhouses now,” he said.

With approval and support from the U.S. Department of Agriculture, the California Department of Food and Agriculture, and the Yolo County Agricultural Commissioner, the university developed and implemented a plan to disinfect the greenhouses on Mar. 1.

Rice plants necessary for continuing research were fumigated with mite pesticide, removed from the greenhouses and securely transported to UC Davis’ Contained Research Facility where they will be preserved under quarantine until their seeds can be harvested and sterilized to kill residual mites. Remaining plants were destroyed using high heat; the greenhouses and the rest of their contents were steam-sanitized.

The greenhouses will remain vacant until the start of the state’s rice planting season on Apr. 1.

Since rice fields are not near the greenhouses, chances are low that rice mites have spread beyond campus, according to Animal and Plant Health Inspection Service program manager Andrea Simao.

Even with statistics on their side, pest management experts advise growers to take precautions to ensure their rice is mite-free.

“We will be on the lookout for this pest this growing season,” said Larry Godfrey, a UC Davis entomologist involved with the UC Statewide Integrated Pest Management Program. “Educating and having all the growers and pest control advisors look for it will leverage our efforts.”

Natalie Hummel, an entomologist from Louisiana State University Agricultural Center who helped develop USDA guidelines for inspecting rice fields, says the panicle rice mite infestations in her state during 2007 dwindled away in the winter and did not return the following year.

“After the mite was detected in Louisiana, we developed and delivered a multi-tier educational program … on scouting for mite,” she said. “Trained eyes and feet on the ground will allow us to detect [the pest] early.”

While there are no management plans or pesticides approved for general use in the U.S. to target panicle rice mite, the USDA has established guidelines to keep the pest from entering the country.

It is not known how rice mites got into the UC Davis greenhouses, but the campus will strive to prevent future infestations by developing and enforcing additional standards for researchers who handle rice plant material, Parrella said.

The affected greenhouses were used by UC Davis researchers for developing and cultivating new varieties of rice plants that can better tolerate drought, flooding and salty soil conditions to improve rice production throughout the world.

ELAINE HSIA can be reached at campus@theaggie.org.

UC Davis professor of wildlife, fish and conservation biology Tim Caro spends his time off in Africa – in a remote corner of Tanzania near the Katavi National Park, to be exact.

Caro studies both animal behavior and what we can do to preserve species. Recently, his research has focused on answering the age-old question, “How did the zebra get his stripes?”

The British native got his degree in zoology at the University of Cambridge, UK followed by his Ph.D. from the University of St. Andrews in 1979. Caro has taught at UC Davis for 20 years and says he does biology “24/7.”

Currently working in Dar es Salaam, Tanzania after a month of isolated fieldwork, Caro was gracious enough to answer a few questions for The California Aggie.

What classes do you teach? Do you have a favorite?

I teach Introduction to Conservation Biology (WFC11) and Behavioral Ecology (WFC141) and some graduate classes. My favorite course is WFC11 – actually I used to teach Conservation Biology at the upper division level but I volunteered to start a new lower division GE course because I think that young broad-minded undergraduates can make a big impact on the environment. WFC11 is an opportunity for me to teach English, engineering and enology students how to make a positive difference to the natural world – not just biologists.

What does your research focus on? Where has it taken you?

Unusually, I work in two different fields of biology, animal behavior (what animals do) and conservation (how we can keep them around). This allows me to do amazingly exciting research and even see my findings take effect. For example, after producing a report on remaining wildlife corridors in Tanzania, we have just found out that the president of that country wants a copy.

I like to do research at full throttle: trapping rodents on the slopes of pyramids in neotropical rainforest, darting cheetahs on the Serengeti Plains, racing after deer in Michigan, counting elephants from 500 feet up and walking through tsetse fly infested forests dressed in colored suits. I often find myself in unexpected situations.

What’s it like doing fieldwork in remote locations?

It is a tremendous privilege to work in the tropics where biodiversity reaches its maximum and to initiate research at sites where no biologist has worked before. Living in remote places requires anticipating difficulties in advance and being flexible. In the tropics, the key is to work hard when the opportunity arises but not to push if there is no obvious way forward. Of course fieldwork is difficult with no e-mail, lattes, running water or electricity – but that’s the fun of it.

What are some of the explanations for the markings of black and white animals you’ve drawn from your research?

Shockingly, we still don’t know the function of black and white markings in animals like giant pandas 150 years after Charles Darwin and Alfred Russel Wallace debated these issues. I am trying to carry on where they left off by conducting research on black and white skunks, zebras and giant anteaters. Everyone knows that skunks are strikingly colored to advertise their ability to spray scent but why should these species need to be so smelly in the first place – why are they so worried (in an evolutionary sense) about predators?

I have spent the last four years conducting the first experiments on coloration in wild zebras and I think I now know the answer to why they have black and white stripes. Not only will I write a boring academic book, but I will teach how one discovers these things, and will write a children’s book on the real (evolutionary) reasons that zebras have this extraordinary coloration.

What is the best way to conserve biodiversity?

The key to biodiversity is that it’s not just the big stuff. The work that I conduct in and around Katavi National Park in western Tanzania has shown that the park protects large charismatic animals like lions and buffalo but there are few of these left outside. Yet outside, where people cut trees or farm, there are plenty of frog, butterfly, tree and rodent species that are not found in the park. This indicates that society cannot write off these poorly protected areas – they still perform the important conservation service of protecting biodiversity.

In your experience, what’s the best way to go about setting up nature preserves?

Right now I am writing a book while on sabbatical in Dar es Salaam, Tanzania about indicator, umbrella, keystone and flagship species. These are just shorthand for how we identify where and by what means we work with society and politicians to set up reserves. There is no single way of doing this and conservation scientists are still struggling to identify sites with many species, and how to manage reserves. Political expediency is probably the key to setting up protected areas but we need the biological background to make informed decisions, as reserves are our best conservation hope until we can find a way to live with wildlife.

Why did you come to UC Davis?

UC Davis has so many high quality professors studying whole organism biology. For evolution and ecology, and perhaps conservation biology, it is the best university in the country. Intellectually, it is extremely exciting if you are biologist who is willing to interact with others. I make a point of trying to collaborate formally with faculty colleagues and this has forced me to become an undergraduate assistant all over again – measuring trees, setting turtle traps, learning how to do mathematical modeling and constructing interview questionnaires. UCD makes well-rounded biologists who look at the big picture.

What’s your favorite animal?

My wife (who is an evolutionary biologist in the anthropology department).

Is there anything else you’d like to tell UC Davis students?

My experience in the world’s disappearing biomes has shown me that biodiversity is declining rapidly and habitats are being fragmented at an alarming rate. You can help by not buying hardwood furniture, not buying exotic pets and lowering your expectations! Think about the environmental consequences of your actions – CO2 production in driving, environmental costs of transportation of out-of-state goods, use of A/C, flying and buying new stuff.

ALYSOUN BONDE can be reached at campus@theaggie.org.