Posts Tagged: Bruce Hammock
Scorpions--to fear or to revere?
The Bohart Museum of Entomology's open house last Sunday drew visitors of all ages who marveled at the scorpions glowing under ultraviolet light.
UC Davis entomology major Alexander Nguyen flashed a UV light on the critters as his audience watched in amazement.
Most--but not all--of the world's scorpions glow under ultraviolet light, says Lynn Kimsey, director of the Bohart Museum, which houses more than seven million insect specimens.
Scorpions are not insects, but arachnids, the same as spiders. Ranging in size from 9 mm to 21 mm, scorpions have eight legs (arachnid alert!) and grasping claws that help conquer their prey. But it's their venom that kills. And all scorpions possess venom.
UC Davis entomologist Bruce Hammock and his lab made the news back in 2003 when they published a study that showed that scorpions produce two venoms: a pre-venom to deter predators and immobilize small prey, and then the good stuff, the powerful venom that's meant to kill.
It's like saving the best for last or waiting for the venom glands to pump and reload, so to speak.
So, why do they glow?
Scientists believe it's because of the fluorescent material found in the scorpion's hard outer covering.
"The fact that they glow serves no physiological function," said Bohart senior museum scientist Steve Heydon. "It's probably a quirk of chemical makeup."
Great quote..."a quirk of chemical makeup."
Scorpion glowing under ultraviolet light at the Bohart Museum of Entomology. (Photo by Kathy Keatley Garvey)
UC Davis entomology undergraduate student Alexander Nguyen flashes a UV light on a scorpion, as Professor Demosthenes Pappagianis, M.D., Ph.D., of Medical Microbiology and Immunology, watches. (Photo by Kathy Keatley Garvey)
That's why we're looking forward to hearing Bryony Bonning speak on "Novel Toxin Delivery Strategies for Management of Pestiferous Aphids" at the next UC Davis Department of Entomology seminar, scheduled from 12:10 to 1 p.m., Wednesday, April 18 in 122 Briggs Hall.
Aphids, Bonning says, transmit more than 275 plant viruses "that result in considerable economic loss within the agricultural sector."
Now that's a lot of plant viruses!
A professor with the Iowa State University's Department of Entomology, Bonning is closely linked to UC Davis. She's a former postdoctoral research associate in the Bruce Hammock lab, Department of Entomology. Hammock, a distinguished professor of entomology, worked with her from 1990 to 1994. Her specialty: genetic engineering and optimization of baculovirus insecticides.
Bonning returns here Wednesday with lots of credentials. She's an associate editor for the Journal of Invertebrate Pathology; a Fellow of the American Association for the Advancement of Science (AAAS); a member of the International Committee on Taxonomy of Viruses, Baculovirus Study Group; and a member of the International Committee on Taxonomy of Viruses, Dicistrovirus/Iflavirus Study Group.
Bonning received her bachelor's degree in zoology from the University of Durham, UK in 1985, and her doctorate in applied entomology from the London School of Hygiene and Tropical Medicine, University of London, UK in 1989.
In her abstract for Wednesday's talk, Bonning explains: "Viruses in the Luteoviridae are obligately transmitted by aphids in a persistent manner that requires virion accumulation in the aphid hemocoel. To enter the hemocoel, the virion must bind and traverse the aphid gut epithelium. The molecular mechanisms involved in this process are poorly understood. By screening a phage display library, we identified a peptide that binds to the gut epithelium of the pea aphid Acyrthosiphon pisum (Harris) and impedes the update of Pea enation mosaic virus from the pea aphid gut into the hemocoel. In this talk, the development of two novel aphid management technologies based on knowledge of pea aphid – Pea enation mosaic virus molecular interactions will be described. These technologies provide enhanced delivery of both gut active and neurotoxic peptides."
"I can hardly wait for Bryony Bonning to visit us and present a seminar," Hammock said. "She is one of our most productive alumni in continuing her work on insect developmental biology and green pesticides based on insect viruses and expanded this dramatically into exciting new areas. She is advancing fundamental virology while applying this knowledge in production agriculture in both insect control and in blocking transmission of plant diseases by insects. She clearly is the leader in insect control with recombinant viruses."
Her April 18th seminar promises to zero in on those dratted pea aphids. The more we know about them, the better we can control them.
And the good news is that many of the UC Davis Department of Entomology's seminars will be videotaped and later posted on UCTV.
Pea aphids on a rose leaf. (Photo by Kathy Keatley Garvey)
Pea aphids claim a rose stem. (Photo by Kathy Keatley Garvey)
From moths to medicine...
When distinguished professor Bruce Hammock of the UC Davis Department of Entomology speaks at the department's noonhour seminar tomorrow (Wednesday, April 6) in 122 Briggs Hall, his topic is sure to draw attention.
Hammock's topic: "Moths to Medicine: Epoxide Hydrolase Inhibitors as Analgesic Agents for Neuropathic and Inflammatory Pain." His talk is the second in the department's spring seminar series.
Hammock began his entomological career studying pest management (insect development), and then added a new dimension, pain management (humans), to his research expertise.
He and his lab were recently featured in an article, "Shotgun Approach to Drugs," published in Chemical and Engineering News.
A member of the National Academy of Sciences and a fellow of the Entomological Society of America, Hammock received the UC Davis Faculty Research Lecture Award in 2001 and the Distinguished Teaching Award for Graduate and Professional Teaching in 2008.
Hammock directs the UC Davis Superfund Research Program, which last year received a $13.2 million, five-year competitive renewal grant from the National Institute of Environmental Health Sciences (NIEHS). He also directs the National Institutes of Health Biotechnology Training Program and the NIEHS Combined Analytical Laboratory.
If you can't make it to his talk, not to worry. It will be webcast and then archived on the department's website. There you can link to other entomology-related webcasts recorded since February 2009.
Professor James R. Carey of the Department of Entomology spearheaded the webcasting of the departmental seminars.
Three University of California entomology professors were among the 10 newly elected Fellows of the Entomological Society of America (ESA) honored at the organization's 58th annual meeting, held Dec. 12-15 in San Diego.
Their selection speaks highly of the caliber of UC professors. No more than 10 Fellows are selected for the honor every year from the 6000-member organization, and this year the UC system has three.
They are Bruce Hammock and Thomas Scott of UC Davis and Thomas A. Miller of UC Riverside.
Hammock, a distinguished professor of entomology, studies "inhibitors of epoxide hydrolases as drugs to treat diabetes, inflammation, ischemia and cardiovascular disease," the ESA statement of his work reads. "Compounds from the UC Davis laboratory are in human trials."
That in itself--from bench to bedside--is unique in the annals of entomology.
Hammock, a member of the UC Davis Medical Center's Cancer Center and the National Academy of Sciences, is not only a distinguished professor but a highly sought-after mentor who draws students to his lab from all over the world.
Scott, who directs the UC Mosquito Research Laboratory at Davis, is one of the key "go-to" researchers studying dengue. When he's not in his UC Davis lab, you can usually find him doing research in Peru, Thailand or Mexico. Scott is especially known for his research on mosquito ecology, evolution of mosquito virus interactions, epidemiology of mosquito-borne disease, and evaluation of novel products and strategies for mosquito control and disease prevention.
Scott is a fellow of the American Association for the Advancement of Science and is a past president of the Society for Vector Ecology. He serves as a subject editor for the American Journal of Tropical Medicine and Hygiene. (More on Hammock and Scott on the UC Davis Department of Entomology website.)
ESA officials pointed out that Miller's research "has included structure and function of the insect circulatory system; mode of action of insecticides; insect neuromuscular physiology; physiology, toxicology and behavior of pink bollworm in cotton fields; transgenic insects; and applied symbiosis for crop protection and biopesticides for crop protection. "
Miller's university teaching includes insect physiology, insect toxicology and first year biology. Current projects include control of bush cricket pests of oil palm trees in Papua New Guinea, oversight of field trials of transgenic grapevines with resistance to Pierce's disease, biotechnology for control of desert locust, and regulatory control of insect transgenic technologies.
In 2003 Miller was awarded the Gregor J. Mendel Medal for Research in Biological Sciences by the Czech Academy of Sciences. That's just one of his many honors.
Indeed, the list of honors and accomplishments for these three UC entomologists could easily fill a book!
Pest management. Pain management.
Early in his career, entomologist Bruce Hammock, now a distinguished professor of entomology at the University of California, Davis and a newly selected fellow of the Entomological Society of America, probed regulating the development of insect larvae.
Now his interests swing toward pain management, including inflammatory diseases like arthritis.
His is truly a case of "from the bench to the bedside."
Today two UC Davis labs--including Hammock's--and a lab from Peking University, China published an article in Proceedings of the National Academy of Sciences (PNAS) that is sure to offer hope down the road for those suffering from arthritis pain.
The scientists found a novel mechanism as to why the long-term, high-dosage use of the well-known arthritis pain medication, Vioxx, led to heart attacks and strokes. Their groundbreaking research, done with rodents, may pave the way for a safer drug for millions of arthritis patients who suffer acute and chronic pain.
“This is a major breakthrough that can lead to a better medication for people suffering from acute pain,” said Hammock, who has a joint appointment at the UC Davis Cancer Center.
The Hammock lab and two others labs--the lab of cell biologist Nipavan Chiamvimonvat, UC Davis Division of Cardiovascular Medicine, and physiologist Yi Zhu, Peking University--used metabolomic profiling to analyze murine (rodent) plasma. They discovered that Vioxx causes a dramatic increase in a regulatory lipid that could be a major contributor to the heart attacks and strokes associated with high levels of the drug and other selective COX-2 inhibitors, known as “coxibs.”
“Our metabolomics study discovered that 20-hydroxyeicosatetrasanoic acid, also known as 20-HETE, contributes to the Vioxx-mediated cardiovascular events,” said UC Davis bioanalytical chemist Jun-Yan Liu, the senior author of the paper and a five-year member of the Bruce Hammock laboratory.
Millions of arthritis patients took Vioxx before its withdrawal from the global market in 2004. Vioxx, a nonsteroidal anti-inflammatory drug (NSAID) and coxib for acute and chronic pain, particularly for arthritis and osteoarthritis, was on the market for five years. Merck & Co. voluntarily withdrew it in September 2004 due to concerns about the increased risk of heart attacks and strokes.
The chronic administration of high levels of selective COX-2 inhibitors, particularly rofecoxib, and valdecoxib, increases the risk for cardiovascular disease, Liu said.
Urologist Ralph devere White, professor of urology at the UC Davis School of Medicine and director of the UC Davis Cancer Center, described the research as “extremely exciting.”
“Vioxx and other drugs in this class were looked on as extremely promising in moderation,” devere White said. “The fact that the Hammock lab discovered why the drug could lead to heart attacks and strokes and is able to quantify the deleterious facts is extremely exciting. I hope that patients can safely use this drug in the future or block the deleterious effects so it will have all of the benefits and none of the adverse side effects.”
Nationally, some 46 million individuals suffer from arthritis. “And almost one million patients are admitted to hospitals every year because of their arthritis,” Hammock said. “They do need effective and safer drugs to relieve their pain.”
This research (see the UC Davis Department of Entomology website) will undoubtedly open up new strategies to develop safer coxibs.