UC Science Today

Racial issues have been widely discussed by sociologists, anthropologists, artists and filmmakers. Now, medical researchers are chiming in with their expertise.

"We’re thinking about race in terms of self-identified race and ethnicity, a very specific measure in the context of biomedical research. And we’re the first group that’s looked at genome-wide molecular signature of race and ethnicity and shown that it differs not for just genetic reasons, but also probably for environmental reasons."

That’s Noah Zaitlen, a professor of medicine at the University of California, San Francisco. He came to this conclusion with his colleagues while studying asthma rates in different ethnic groups.

"It’s very high in Puerto Ricans. It’s high in African-Americans. It’s very low in Mexicans."

So Zaitlen wanted to know why. He says if doctors looked not only at these groups’ genetics, but also at the communities they live in and the air that they breathe, they might have improved their diagnosis and treatments.

There may soon be a new way to treat multiple sclerosis, a debilitating autoimmune disease. Neurologist Bruce Cree of the University of California, San Francisco has been testing an experimental medication called ocrelizumab, which suppresses the immune system’s B-cells, which are a class of white blood cells.

"And we think that B cells potentially play a very important role in multiple sclerosis.”

Most existing MS drugs target T-cells and there are more side effects.

“Because when you just target B cells without affecting T-cells, you have less of a potential for adverse events due to broad spectrum immune suppression. I think that’s the key distinction. I think the big advantage for B cell directed therapy in multiple sclerosis is going to be the ability to have highly effective treatment with a better tolerated and improved side effect profile for our patients."

PHOTOGRAPH: Hugo Paice

Researchers may have underestimated the amount of methane emitted into the atmosphere in certain parts of the country. That’s according to physicist Marc Fisher of the Lawrence Berkeley National Laboratory.

“We conducted a study of methane emissions from San Francisco Bay Area and we found that emissions are roughly one and a half to two times the emissions expected based on inventory estimates, counting how many landfills, how many cows, how many wastewater treatment plants, how many different things that might emit methane.”

So what does this discovery mean for us?

“From a human health perspective methane itself is not a hazard unless it reaches such high levels that it combusts, but it is a very potent greenhouse gas."

And this requires better management of the pollutant sources, like landfills, to reduce its contribution to climate change.

Here are some of the stories covered this week on Science Today. Multiple sclerosis is a chronic disease that can paralyze the brain and spinal cord when the immune system attacks the body. MS affects about 2 million people globally and while there is no cure for the chronic disease, drug regimens and behavioral therapy have allowed people with MS to lead better quality lives. Now, neurologist Bruce Cree of UC San Francisco has been testing a drug in clinical trial that’s designed to reduce MS symptoms – in fact, Cree found that patients’ brain inflammation was practically gone.

“This was very impressive and suggests that we have a highly effective therapy. There is some advantage in medication in terms of tolerability, in terms of efficacy and I think it’s going to be a very important new therapy."

It’s called ocrelizumab and it’s currently under review by the FDA. While at UCSF, we also checked in with researchers hoping to improve a powerful gene editing tool called CRISPR, which scientists hope can one day treat genetic disorders. Microbiologist Benjamin Rauch explains that the technology hasn’t been precise enough.

"CRISPR is not perfect; CRISPR will cut DNA in the wrong place if we give it enough time to do so. You can’t edit in the wrong place because it will have some negative effects."

So they’re working with so-called anti-CRISPR proteins that they found can stop CRISPR before it makes the wrong cut. This is a story we’ll definitely keep track of because a safer more accurate CRISPR brings scientists a step closer to developing an effective DNA-editing therapy in the future. And finally, UC San Diego’s Catherine Marinac is looking into simple and novel ways to reduce a woman’s risk of breast cancer. She found that fasting at least 12 hours overnight may help because women who fasted longer had better control over their blood sugar connections.

"We know that it influences inflammation and many of these metabolic factors are related, so you’ll typically see abnormal glucose with inflammation. We know it influences some parameters related to Circadian rhythms and Circadian misalignment and all of these things are on the same cascade. So, we don’t know the exact mechanism, but that’s currently being investigated in animals."

Stay on top of the latest University of California research – subscribe to Science Today on iTunes of follow us on Facebook. Until next time, I’m Larissa Branin.

Subscribe to Science Today:

iTunes: apple.co/1TQBewD

Stitcher: www.stitcher.com/podcast/science-today

Follow us on Facebook: www.facebook.com/ucsciencetoday

Stories mentioned in this roundup:

https://soundcloud.com/sciencetoday/ms_strategy

https://soundcloud.com/sciencetoday/crispr_edit

https://soundcloud.com/sciencetoday/fasting_cancer

If you want to protect yourself from a dangerous foodborne infection called Listeriosis, don’t store food in the fridge for too long.

“A lot of bacteria can’t grow when you store the food in the refrigerator, but Listeria is actually one of the few things that can grow at refrigerator temperature. ”

That’s a piece of advice from microbiologist Anna Bakardjiev of the University of California, San Francisco. She’s studied the bacteria Listeria, which causes the disease, and says it’s not very choosy.

“Cheeses or fruits, there was an outbreak associated with coleslaw where the cabbage had been in the cool house for a relatively long time. Any kind of food had been implicated.”

So Bakardjiev says to prevent an infection that sickens hundreds of Americans every year, eat your food while it’s still fresh. And if you do have leftovers, like stew, reheat it thoroughly.

When you fill out forms at the doctor’s office, you often have to check off boxes to identify as Caucasian, Hispanic, Asian or African–American. Noah Zaitlen of the University of California, San Francisco, says that’s because people of different ethnic backgrounds respond differently to medication and treatments. Still, Zailten says this method is far from perfect; in fact, he found adding social and environmental factors may be just as important.

"What would happen in a hospital system if instead of saying you can be Latino, let people tell me more about what community they identify with. Could we do a better job of practicing medicine if we sort of broaden these categories or maybe used some genetics to help enrich the community identification?”

So Zaitlin suggests doctors collect more information about exposure to pollutants or stress.

”And if we collected extra information, how much of the difference between drug response, diagnostic ranges, disease prevalence does that explain? And how much would that help us in the clinic?"

Researchers have found a new strategy for treating multiple sclerosis, which affects about 2 million people globally. This chronic disease is incurable and can paralyze the brain and spinal cord when the immune system attacks the body. The progressive form of the disease is especially dangerous.

"And it is typically characterized by weakness and numbness in a leg, then spreading to the other leg and gradually involving more and more of body in terms of disability."

That’s neurologist Bruce Cree of the University of California, San Francisco. He’s been testing a new drug in clinical trial that’s designed to reduce MS symptoms and found that patients’ brain inflammation was practically gone.

"This was very impressive and suggests that we have a highly effective therapy. There is some advantage in medication in terms of tolerability, in terms of efficacy and I think it’s going to be a very important new therapy."

The drug is called ocrelizumab and it’s currently under review by the Food and Drug Administration.

Researchers might have found a way to improve a powerful gene editing tool called CRISPR, which scientists hope can one day treat genetic disorders. According to microbiologist Benjamin Rauch of the University of California, San Francisco, the technology hasn't been precise enough and often makes mistakes.

"CRISPR is not perfect. CRISPR will actually cut DNA in the wrong place, if we give it enough time to do so. You can't edit in the wrong place, because it will have some negative effects."

So called anti-CRISPR proteins that Rauch and his colleagues recently discovered could stop CRISPR before it makes the wrong cut. The researchers basically used bacterial viruses to replicate what happens in nature.

“CRISPR's job in nature is to kill virus by cutting its DNA. So virus by encoding anti-CRISPR is able to fight back against CRISPR."

Rauch says a safer and more accurate CRISPR brings scientists a step closer to developing an effective DNA-editing therapy in the future.

This week on Science Today – we looked into how race and ethnicity affect health. Noah Zaitlen at the University of California, San Francisco, describes the connection they found in their new research.

"People from different countries, from different communities, get sick from different diseases, they respond differently to different medications. We know that some of that is because of differences in their genetics and some of that is because of differences in their environment."

And that includes exposure to pollution or differences in diet or stress levels – all of which doctors and scientists alike overlooked in the past in favor of genetics and ancestry. So Zaitlen hopes doctors will start including this information in their usual form, as it's a better way to assess a patient’s health. And on the subject of patients and health, wouldn’t it be wonderful if cancer patients did not suffer from the systemic toxicity of chemotherapy? We talked to a materials scientist Chelsea Chen at the Berkeley Lab who has been collaborating with a UCSF physician to design a device to do just that.

"What he came up with is that he wants to place this device at the draining vein exiting the tumor, so this device can catch the excessive chemotherapy before it enters the body circulation and this way, it further reduces the systemic toxicity of the drugs. So we designed this device that we call the ChemoFilter."

Hopefully this will be ready for treatment in a few years. And finally, do you snack a lot during the day? If so, your teeth are at risk. Dr. Peter Rechmann of the UCSF School of Dentistry says one tip to reduce cavities is to eat fast.

"We kept on telling our patients you can have chocolate, no problem, eat the whole thing in 10 minutes and brush your teeth or use chewing gum, but don’t eat the chocolate over, piece-by-piece, ever 10 minutes a piece. That is terrible."

The problem is, it leaves more sugar for bacteria in your mouth. For you snackers out there one tip is to munch on nuts – Rechmann says it’s one of the safest snacks because there’s not a lot of sugar for bacteria and it kills your hunger pangs pretty fast. So, how’s that for food for thought? To hear more University of California research stories, subscribe to Science Today on iTunes or follow us on Soundcloud or Facebook. Thanks for listening, I’m Larissa Branin.

Subscribe to Science Today:

iTunes: apple.co/1TQBewD

Stitcher: www.stitcher.com/podcast/science-today

Follow us on Facebook: www.facebook.com/ucsciencetoday

Stories mentioned in this roundup:

https://soundcloud.com/sciencetoday/race_health

https://soundcloud.com/sciencetoday/filter_chemo

https://soundcloud.com/sciencetoday/teeth_snacks

Researchers at the University of California, San Francisco have recently discovered the origin of Listeriosis. This is a foodborne disease that often strikes pregnant women and could affect the fetus, too. Microbiologist Anna Bakardjiev discovered a protein secreted by Listeria bacteria attacks the placenta – and this was surprising to her.

"There are only very few pathogens that can infect the placenta and the baby during pregnancy. Placenta and the fetus are very protected against infection."

But that specific protein has found a way to break through the placenta's protective barrier and help bacteria grow there rapidly. These findings challenge current thinking that a pregnant woman's weakened immune system increases susceptibility to the infection.

"This is the first time I think for any kind of infection that we have identified the protein that is specifically important for the infection of the placenta."

Bakardjiev says, this could help scientists develop new strategies to prevent and treat Listeriosis and other pregnancy complications triggered by infections.