UC Science Today

People with negative biases tend to focus heavily on negative thoughts or outcomes. Psychologist Sonia Bishop of the University of California, Berkeley says that negativity bias is common in individuals with high anxiety.

"If you ask people to say how likely is it that something bad will happen to me in the future or something good or if you ask people to pay attention to different things, what you'll find quite often is that Individuals high in anxiety will show this tendency to find it easier to switch their attention towards something which is negative, that they may remember more negative things, and that they may also judge that negative events are more likely happen to them in the future."

Bishop says that this can influence our decision-making and risk-taking behaviors.

"We think that that may well be influenced by some of these problems of decision-making. Because if you can't understand why something happened that seemed to be very negative, then maybe you would be much more worried about negative events happening in the future."

Accelerator Mass Spectrometry, or AMS, is a technique for measuring isotope ratios with very high selectively, sensitivity and precision. It was originally developed as a geophysical instrument to do carbon dating of artifacts. About two decades ago, the Lawrence Livermore National Laboratory developed it to do biomedical applications.

"We were kind of the pioneers in that front and it’s just kind of taken off from there. We’ve looked at low levels of environmental toxicants and now we’re getting into the human area so we can do actual real world human experiments using this type of technology."

That’s medical scientist Mike Malfatti of the Livermore Lab. He’s been using a new biological AMS instrument to develop a test to predict how people will respond to chemotherapeutic drugs. Malfatti and this team have been working with colleagues at the University of California, Davis.

"It’s really opened up a lot of opportunities for us – almost a whole new field of study being able to actually do real in-human studies where previously those studies weren’t able to be done."

In the pharmaceutical industry, making a new drug costs an average of $5 billion and can take anywhere from ten to fifteen years to develop. Bioengineering professor Kevin Healy of the University of California, Berkeley says a large part of the problem is because preclinical trials rely heavily on animal models that don’t translate well to humans.

"Animals are not humans, they don’t have the same response to drugs. Many well-known experts in the field will tell you that the animal experiments really aren’t very good predictors of drug function. They do help out with safety, but not efficacy or performance of the drug."

So, Healy’s team developed a small cardiac chip that effectively models how the human heart responds to drugs. He says that the device could significantly cut the time and cost it takes to develop a drug.

"We believe, ultimately, if we and others are successful in developing various microphysiological systems, we’ll have a significant improvement in both."

Pupil dilation typically occurs when we process new information or respond to changing environments. But in a recent University of California, Berkeley study, researchers have found that weaker pupil response is associated with high anxiety. Study leader Sonia Bishop says that this suggests why highly anxious individuals may find it harder to make decisions in volatile environments.

"In low anxious individuals, their pupils really track information in volatile or changeable situation. And so it’s suggesting that there’s this implicit processing of that information which is working well. But in high anxious individuals, we don’t see that tracking, so their pupils are not responsive to their information. So this suggests there’s something wrong in that system of the brain which deals with sending out that signal that this is important information."

Bishop says that the findings may lead to better therapies and targeted drugs for anxiety.

"So one suggestion could be that that system is kind of misfiring and if we give people drugs based on that system, we might be able to normalize it."

It’s long been thought that neurons that form a hunger circuit in your brain basically determine whether or not you take the next bite of food – that it’s controlling the chewing and swallowing associated with food intake. But a study led by physiologist Zachary Knight of the University of California, San Francisco found in mice that these neurons are actually controlled by the sensory detection of food.

"The discovery suggests that that their primary purpose is actually to promote food discovery – to promote foraging, this act of getting motivated to go out into the world and search for food. Evolutionarily, that makes a lot of sense because if you’re a mouse that’s out in the wild and you probably don’t have access to a lot of food on a regular basis and so the really key decision you need to make is when you are going to risk your life by predation, by going out and searching for food. And so the decision that the mouse really needs to get right, and that evolution would have shaped, is the decision to search for food. So, the neuromechanisms that control the actual decision, to take the next bite are one, probably different and two, probably under weaker control than this decision to search for food."

Biologists at the Lawrence Livermore National Laboratory have been collaborating with a host of scientists and putting their Microbial Detection Array to good use. Biologist Crystal Jaing explains that their lab-developed biological detection technology contains over 300 thousand probes that are used to detect thousands of viruses and bacteria. They currently have a couple of collaboration with the University of California, Davis.

"So, one is in the cancer field, look at lymphoma samples and identify pathogen association with a different kind of lymphoma. And we also have discussions with other researchers in terms of looking for antimicrobial resistance because there are a number of pathologies that are common hospital-acquired infections and very often they are kid of a multi-drug resistance. And so those are the type of application we can potentially use this technology for, to rapidly identify those pathogens and identify the antimicrobial profile for those pathogens as well."

Controlling a plant’s stress tolerance can have a significant effect on agriculture worldwide. At the University of California, Riverside, plant cell biologist Sean Cutler found that a naturally produced stress hormone in plants called abscisic acid, or ABA, helps plants survive by inhibiting their growth in times of stress, like drought.

"We came at this from a chemical perspective and my lab now is working on trying to improve these chemicals and create new sorts of options for controlling stress tolerance in the field."

As California faces its worst drought in history – Cutler’s research couldn’t come at a better time. While there’s still more work to be done, earlier this year his lab tested a reengineered version of ABA and were able to revive tomato plants that went 12 days without water. Plants without the reengineered receptor died.

"We certainly can’t claim that we’ve solved the problem, but a lot of people in this field believe that this particular molecule and its pathway is critical to moving forward in that area."

For the first time, bioengineers at the University of California, Berkeley have developed a cardiac system that models how the human heart responds to drugs. Study leader Kevin Healy says that the inch-long cardiac chip, derived from adult stem cells, is a major step forward in developing a faster and more accurate drug-screening tool.

"I think the major use for this will be preclinical trials for drug screening, and how you would screen different drugs, and ultimately replace animal experiments, which many would argue are inefficient, sort of broken. They’re not very good at predicting human clinical response to certain drugs."

Healy says that the cardiac chip could also significantly improve the cost and time it takes to develop a drug.

"We would drastically reduce the cost of drug discovery, and the duration. Saving the pharmaceutical industry and healthcare industry significant cost savings when treating patients."

As the number of adults in the United States over age sixty-five continues to rise, it’s become more important to help these seniors stay healthy. Neuroscientist Julene Johnson of the University of California, San Francisco says that aside from the typical approaches of eating right, sleeping well, and exercising regularly, singing in a choir could also have positive health benefits.

"It requires attention as you pay attention to the choir conductor. And of course singing involves articulation and language. And so it’s possible that singing in a choir will help engage those memory networks of the brain, but also more executive function."

Johnson says that the social and physical aspects of singing in a choir may also contribute to better overall health. If the results from her study are positive, she hopes that it could make creative arts more available for older adults.

"We hope that it could change some policy in terms of making the arts more available for older adults, or in general through the lifespan."

The ability to use computational models for engineering applications has advanced so much in just the last decade. Mechanical engineer Lee Glascoe of the Computational Engineering Division at the Lawrence Livermore National Laboratory used advanced 3-D modeling to ensure that soil filter design standards for dams dating back over 50 years are still valid in the event of an earthquake.

"The advances in numerical techniques and the advances in high-performance computing allow us to address problems that we just simply could not address 10 years ago, let alone twenty years ago. I remember when I first started at the laboratories, I actually started at Los Alamos before coming to Lawrence Livermore, and I was just amazed that we were able to model anything in three dimensions! Everybody’s doing that now, but that next breakthrough in high-performance computing really can make the different in addressing things down to the grain scale. So, it’s really transformed the community."