EXPLORING THE CHEMICAL SENSES - C&EN Global Enterprise

Jan 7, 2002 - IN THE AFTERMATH OF THE SEPT. 11 ATtacks on the World Trade Center, Wall Street Journal reporter Stefan Fatsis wanted to know what ...
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SCIENCE & TECHNOLOGY BREATHTAKINGAsample of mouth air from a volunteer is directed to a gas chromatograph for analysis of volatile sulfur compounds in breath odor.

EXPLORING THE CHEMICAL SENSES Research at Monell Chemical Senses Center encompasses sex, health, nutrition, and more A. MAUREEN ROUHI, C&EN WASHING

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tacks on the World Trade Center, Wall Street Journal reporter Stefan Fatsis wanted to know what was causing the "persistent and weird" odor in New York City. To find out, he turned to the Monell Chemical Senses Center in Philadelphia. The center is the world's first research institute devoted to the multidisciplinary study of the chemical senses. Work there includes probing human pheromones, inquiring about food cravings, sniffing out body odors, understanding chemically induced sensations beyond taste and smell, and controlling environmental malodors. The center attracts the interest of companies in the food, fragrance, beverage, tobacco, chemical, pharmaceutical, and personal care industries. Monell also interests ordinary folks. People with taste, smell, or body-odor disorders may find help at Monell. Couples in crosscultural relationships maybe comforted by information about the origin of food preferences and how individuals vary in their propensity to sample unfamiliar food. Workers exposed to volatile chemicals want to know: Is this chemical really bad 2U

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for my health, or do I find it irritating just because I don't like its smell? Employers are curious: Is there a magic odor that can be put in ventilation systems that will keep employees alert, motivated, and working hard? From basic studies of the mechanism and function of the chemical senses to explorations of how the chemical senses frame our perceptions of reality, work at Monell illuminates many facets of the human condition and advances our quality of life. Take, for example, the visit of Monell associate member Pamela Dalton to New York City last October, in response to Fatsis' query During her visit to New "fork City Dalton—a cognitive psychologist whose work focuses on how odor affects people—smelled the unpleasant Dalton odor that had been troubling Fatsis. She believes that New Yorkers, on smelling this odor later, "could reexperience the same emotions that they were having" in the aftermath of Sept. 11. Odors usually are remembered in asso-

ciation with events, Dalton says. So, an odor linked to an adverse event often can trigger a physiological response that the person attributes to the components of the odor rather than to the bad experience the odor evokes. With two postdoctoral researchers, Dalton collected air samples in and around Ground Zero. At Monell, analysis of the air samples so far indicate the presence of acids (acetic acid and nonanoic acid), aldehydes (formaldehyde and benzaldehyde), aromatic hydrocarbons (benzene and styrene), mercaptans, guaiacol, and diethyl phthalate. Dalton is now correlating the chemicals to the odor. When the components of the pervasive odor are identified, Dalton hopes to recreate it. "The recreation of this smell," she says, "may assist some therapists in helping some New Yorkers deal with post Sept. 11 stress," just as Dalton once helped herself deal with a bad experience. MANY YEARS AGOp Dalton tells C&EN, she was mugged. Months after the incident, she began having panic attacks whenever she smelled modeling glue. Then she figured out that the smell reminded her of the attacker, who must have been a glue sniffer. "I went to a craft store, bought modeling glue, and taught myself to break the spell of that smell" by experiencing it in a safe environment. "Now the smell has no emotional hold over me anymore." W h e n people recognize that an odor that's causing physiological stress is really triggering unpleasant memories, they can be taught to break that association, Dalton says. The hypothesis is that when people smell the odor and nothing bad happens, then they can learn that the odor no longer predicts an adverse outcome. Dalton is testing the hypothesis and believes that it can be applied to war veterans experiencing post-traumatic stress disorder. "Wars have distinctive odors associated with them," she says. Veterans of the Vietnam War remember the smell of jet fuel, napalm, and burning organic matter, among others. Those who served in the Gulf War remember the smell of certain insect repellents. "We think that when HTTP://PUBS. AC5.ORG/CEN

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he task of forcing the terrorist Osama bin Laden and members of his inner circle from the caves of eastern Afghanistan might have been easier had U.S. forces used bombs with odor power in addition to firepower. If a conventional bomb misses its target, that's it. Odors, on the other hand, permeate to areas distant from the source. The idea is not far-fetched. The U.S. military already has asked the Monell Chemical Senses Center to formulate bad smells for potential application in dispersing crowds and in preventing entry to designated spaces. The odors are nonlethal. They are due to compounds that can be detected by humans at levels way below the concentration at which the compounds become irritants or health hazards. The U.S. military is studying how to

these veterans smell these odors later, when they're back in the safety of their communities, the odors may act like a flashback trigger." In a project being funded by the U.S. military, Dalton will study how to weaken the impact of the odors of war. For analysis of odors, Dalton is collaborating with Monell staff member George Preti, an organic chemist. Such cross-disciplinary collaborations are standard at Monell. According to Mary M. Chatterton, MonelTs director of resource development, the center was designed to foster such interactions. 'We have no departments, no divisions," Chatterton tells C&EN. She says that MonelTs founder, Morley R. Kare, a pioneer in the study of smell and taste, "thought that by mixing up offices and putting a psychologist next door to a chemist, people would just naturally talk about their work in hallways and be much more likely to collaborate." MonelTs funding comes primarily from grants from the government (50%), corporations (30%), and various foundations. Only unrestricted grants are accepted from corporate sponsors. Every project is intended to be published. When companies ask for help with their products, "we send them to commercial labs," Chatterton says. However, with

make weapons out of stinky odors that have been formulated at Monell. Tests carried out by Monell associate member Pamela Dalton show that these odors are potent in making people want to flee in disgust. "People really hated these odors," Dalton tells C&EN. "As they smelled the odor, their heads would jerk back, and you could see the revulsion on their faces." Physiological monitoring shows that the odors induce shallow breathing, increased heart rate, and increased stomach motility, which is an early indicator of nausea. In designing the bad-odor mixtures, Dalton says, "we homed in on biological odors because we thought those had the best chance of being recognized universally." Among them are the smell of rotting garbage, human waste, and burnt hair. Common ingredients of the mixtures are skatole and mercaptoacetic acid.

one of constant intellectual renewal. People who came here as postdocs, myself included, are continually doing new things. That's what keeps us here." AS DIRECTORp Beauchamp must ensure that Monell continues to be a vibrant and leading research institution for the chemical senses. "The only way to do it is to provide the resources and the freedom the investigators need," he tells C&EN. MonelTs location in Philadelphia's academic center—its neighbors include the University of Pennsylvania and Drexel University—allows its researchers to draw upon a culturally diverse pool ofvolunteers for its human studies and a deep well of expertise in various disciplines from which its researchers draw collaborators. Currently the center occupies 60,000 sq ft of space in one building. That may be increased by up to 25%, Beauchamp says, to allow expansion of research in regeneration, development, and aging in the chemical senses. The center also plans to bring in more people with expertise in biophysics, biochemistry, neuroscience, molecular biology, and molecular genetics. Of particular interest to the center are researchers with expertise in human sensory perception. Very few people in the U.S. are being trained in the chemical senses, Beauchamp notes. In the past, Monell has tended to bring in people at a junior level and then

sponsorship, companies gain access to MonelTs know-how. Corporate sponsors "can call any of our scientists and ask, 'What do you know about this? Can you send me a paper on that? Can you speak at a meeting for us?'" The access lets industry in on cuttingedge research even before it is made public, says Monell staff member CharlesJ. Wysocki. "Sometimes, we get stung by this practice," he adds, referring to the race to find a sweet receptor. Industry knew that Monell was getting close, Wysocki tells C&EN. He thinks the information reached other groups on the trail of a sweet receptor, who then shifted their efforts to even higher gear and got to the finish line first. At any given time, about 50 Ph.D. scientists from a wide range Preti of specialties work in the center. Wysocki The almost totally unfettered freetrain them. Although it has been successdom to ask questions and seek answers moful, that route is difficult, Beauchamp says. tivates researchers, several ofwhom joined "We're casting our net worldwide to find Monell as postdocs and then chose to stay people." MonelTs staff is "one of the things that The multidisciplinary collaborative spirmakes this a fine and exciting place," says it allows Monell researchers to venture way Gary K. Beauchamp, abiopsychologist and out of their expertise, and Monell staff typthe center's director. "Here, you have to ically have projects all over the landscape. learn a bit of chemistry ifyou're a biologist Take Wysocki, a psychobiologist by trainand vice versa. That has made the place

"Each of us has our own reality, and it is based on what we perceive through our sensory systems/' HTTP://PUBS.ACS.ORG/CEN

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SCIENCE & TECHNOLOGY ing. His projects range from the very basic—understanding the basis of human differences in olfaction—to the very applied—how to make pig farms or mushroom compost less stinky Nobody would choose to live where the air smells of pig slurry or spent mushroom compost—a mixture of hay, gypsum, and chicken and horse manures. As housing developments move into rural areas, however, people are increasingly bothered by odors from pig and mushroom farms, which are important to Pennsylvania's economy With Preti, Wysocki has been working with the Pennsylvania Department of Agriculture to seek ways to ameliorate the odors coming from those farms. In terms of improving the human condition or the quality of life, the agricultural work has a very direct impact on the neighbors of those farms,^Xfysocki says. But those neighbors are a small segment of the population. His work toward elucidating the variability of human olfaction, he believes, could have far greater consequences. "EACH OF US has our own reality, and it is based on what we perceive through our sensory systems," Wysocki tells C&EN. There is good evidence that great variations exist in the human sense of smell. So wherever smell plays a role—in foods, flavors, fragrances, or even in people's enjoyment of gardens—then different perceptions exist, he explains. "It's hard to get into somebody else's brain to understand what they're perceiving," Wysocki continues. "But if we understand that differences in perception exist that may have a biological basis or may be environmentally induced, we are a step toward accepting individual differences and diversity" Wysocki has been studying the variations in human olfaction at myriad levels: age, sex, disease, genetics, environment, and experience. "Individuals who work in a constant-odor environment—a pulp mill, a paint factory or a fragrance companywill have a different sense of smell from a person who works in an odor-free environment," he says. "I've been studying how different factors make their contributions and where they show their effects." There's smelly research, and there's sexy research. In the area of chemical communication by humans, Preti and Wysocki manage to combine both. One project involves male underarm secretions and whether they harbor human pheromones. Many Internet sites peddle products containing what are claimed to be human pheromones. These products—touted as 26

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The Body-Odor Doctor Is In

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or some people, George Preti, an organic chemist and a staff member at the Monell Chemical Senses Center, is the only doctor they can turn to. Preti holds a doctorate in organic chemistry, not a medical degree. However, his expertise on human body odors based on three decades of research on the nature, origin, and function of human odors has drawn patients to his lab. Among them are people with the little-known genetic disease called trimethylaminuria, or fish odor syndrome. People with extreme forms of this disease sporadically smell like fish—no matter how often they bathe and change their clothes. Their social lives are wrecked. Compounding the misery is that the smell isn't always there. Often when patients seek medical help, physicians can't even smell the problem. If they're willing to wait, patients can be examined in the lab of Preti, who is one of the very few researchers who can diagnose trimethylaminuria. The lab is not a clinic, he says. "So we see one patient a week when we can see them." Preti has developed a diagnostic scheme for patients presenting odor-related problems. Using his own nose, he first assesses the level of breath and body odor produced by a patient—who is instructed to not use deodorants or antiperspirants for three days before the consultation, to not practice any oral hygiene the night before, and to wear clothing with easy access to the armpits. "I don't stick my nose in the underarms," Preti says. But he does apply a swab to the underarms to sample the bacteria there. "When I'm taking the sample, I get very close. So if there's a lot of odor being produced, I can smell it." The swab goes to the cutaneous microbiology lab at the dermatology department of the University of Pennsylvania, where Preti's collaborators look at the types and levels of bacteria from the patient's armpits. "That gives me an idea of the patient's odor-producing capability." Next, Preti looks at the air in the patient's mouth for bad-breath-causing compounds. He puts a tube in the patient's mouth and pulls a sample of breath directly into a gas chromatograph. He also collects saliva for analysis of less volatile compounds. Then comes the choline challenge test, developed by a collaborator of Preti's,

Paul V. Fennessey, a professor of pediatrics and pharmacology at the University of Colorado Health Sciences Center, Denver. The patient ingests 5 g of choline dissolved in orange juice and collects a urine sample every eight hours for 24 hours. If a patient has trimethylaminuria, the culprit—trimethylamine—will show up here. Trimethylaminuria is caused by defects in a flavin-containing monooxygenase called FM03. This enzyme catalyzes oxidation of fish-smelling trimethylamine—produced by bacterial degradation of dietary choline in the large intestine—to odorless trimethylamine oxide. A person with defective FM03 accumulates trimethylamine and excretes it in urine and sweat. Finally, the patient gives a blood sample, which is analyzed by Preti's collaborators in the medical school for genetic abnormalities related to trimethylaminuria. The workup in Preti's lab takes between two and two-and-a-half hours. Preti says he devotes a significant amount of time talking to patients about why and how body odors are produced. He gives them copies of popular magazine articles based on interviews with him about bad breath and body odors. With the organoleptic, analytical, biochemical, and genetic analyses, a fairly complete picture emerges, and Preti can tell with great confidence if a patient has trimethylaminuria. For patients who have the disease, he tells them how to alleviate symptoms. For example, avoid foods high in choline, such as eggs, legumes, soy products, organ meats, and saltwater fish. Or take antibiotics such as metronidazole or neomycin. These will reduce the bacterial population in the intestine and temporarily halt the production of trimethylamine. This measure is particularly effective for patients who are anticipating a special occasion—a wedding, for example—and want to be sure they don't emit embarrassing odors, he notes. However, Preti can't prescribe antibiotics. "I write every patient an extensive report, which I ask them to show to their doctors so they can get a prescription," he says. "If you have a body-odor-production problem, chances are your doctor may not know what you're talking about. So I ask my patients to educate their doctors." Don't patients mind that he's not a "real" doctor? "Who else are they gonna call?" Preti replies.

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LANDMARK Face Fragment, by Arlene Love, marks the entrance of the Monell Chemical Senses Center at 3500 Market St. in Philadelphia.

"invisible social magnets" or "nature's aphrodisiac"—promise that the wearer will be instantly irresistible to the opposite sex. The products take advantage of the public's ignorance of what pheromones do, Wysocki explains. Androstenone, for example—the pheromone of male pigs and the "active ingredient" in many pheromone perfumes—is called a releaser pheromone because it releases a sequence of gross behavioral changes when it is detected by a sow in heat: The sow arches its back, assumes the mating stance, and is ready to mate. "There is no good evidence that the kind of pheromones people are selling releases a specific behavioral sequence in humans," he says.

Pelchat

Bryant

However, a more subtle type of pheromone, called primer pheromones, affects female reproductive development, cyclicity in females, and female hormonal surges. For example, in 1998, researchers at the University of Chicago showed that secretions from female armpits cause women who live together to have synchronous menstrual periods. The work is HTTP://PUBS.ACS.ORG/CEN

regarded as the first real proof of chemical communication among women. According to Preti, evidence had been developing in the early 1980s that male underarm secretions may have substances that can alter the menstrual cycle of females. That humans may produce substances at low levels that can affect something as important as the reproductive endocrinology of the opposite sex spurred Preti's interest in male armpit chemistry With Wysocki, Preti is studying whether male underarm secretions may alter the menstrual cycle. They have been looking at levels of luteinizing hormone (LH)—the hormone that induces ovulation—and how those are affected in women exposed to male armpit secretions by application of an extract to women's upper lips. Over the course of a day—especially before ovulation—levels of LH pulse about every 90 minutes. Just before ovulation, a huge spike in LH occurs, which stimulates the release of an egg. Preti and Wysocki are examining the pulse intervals before the huge spike to see if they are affected by male underarm secretions. An effect would support the notion that the male armpit is a source of a primer pheromone that mediates chemical communication between men and women. If something in the extracts could alter the timing of ovulation, whatever it is, women may be able to use it to schedule when to release an egg. And if an effect exists, it could be used as a bioassay to guide the identification of the active ingredients in male underarm secretions.

ometimes what people decide to eat seems almost beyond their control. Ever wonder why every so often some people just have to have chocolate, a cookie, or a potato chip? The desire is so intense that people go out of their way to satisfy the food craving. Research by Marcia Levin Pelchat, an associate member at the Monell Chemical Senses Center, is helping to understand what cravings are all about. A food craving is not a response to hunger: Any food will satisfy hunger, but only the craved food can satisfy a craving, Pelchat says. It is also not simply a response to nutritional or caloric deficiencies, as is widely believed. The phenomenon is complexinfluenced by age, sex, brain chemistry, hormonal status, nutritional status, psychological state, and environmental cues. The good news is that food cravings diminish with age, although why that is so is not clear. Food cravings can be triggered by sensory stimulation, Pelchat says, so diminution of the senses of taste and smell as people age could be one reason. Women are more prone to food cravings than men, Pelchat finds. In her studies, 100% of young women report food cravings, compared with only 70% of young men. And among those who are at least 65 years old, 70% of women report cravings, compared with only 50% of men. Pelchat also finds sex differences in the foods craved. Women report a 60%M0% preference for sweet foods over savory foods. Men report the same split for savory foods over sweet foods. Pelchat's findings are based on studies in the U.S. With the help of collaborators with expertise in social psychology and anthropology, she plans to examine cultural effects on food cravings. For example, why is black licorice such a highly craved food in Europe? For people who want or need to curb their food cravings, Pelchat has the following tips: Stick to a healthy and sensory-stimulating diet. Keep only small amounts of the foods craved at home. Learn to satisfy the craving with a limited amount of the food.

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SCIENCE & TECHNOLOGY The winter holidays present dom blob. Since older people many opportunities to indulge are more sensitive to irritants, in a very sensual activity: eating. food preparers should hold off Research at Monell is helping on spices and use herbs instead people understand the factors to enhance flavors. The elderthat influence their choice of ly themselves should chew food and drink at different more slowly to allow more flastages of life. vor components to permeate the oral and nasal cavities. At one end of the spectrum, Monell staff memberJulie MenMonell's mission is "to adnella, a biopsychologist, works vance knowledge of the mechwith pregnant women and studanisms and functions of the ies how their flavor preferences chemical senses: taste, smell, shape the food preferences of and chemosensory irritation." their babies as they develop inMost people are familiar with to toddlers. Herwork has shown NOSE JOB Researcher measures changes in congestion, taste and smell as chemically that even while in utero, babies swelling, or blood circulation in the nose of a volunteer after induced senses. Chemosensoare exposed not only to what the exposure to a volatile chemical. ry irritations sometimes are mother eats and drinks but also perceived as either taste or to the perfume she wears. If breast-fed, the smell because of their association with "Many elderly people living in institubaby is further exposed through the mothfoods and beverages—for example, the tionalized settings fail to thrive or risk beer's milk. These early exposures, Mennella's heat of chili pepper and the tingling caused coming nutritionally deficient because they work has shown, shape a child's preferences. by carbonated drinks. The sting in the noscan't enjoy the food," Pelchat tells C&EN. She has found, for example, that infants of tril caused by a whiff of ammonia or acetic When people have to eat homogenized women who regularly drank carrot juice acid is also a chemosensory irritation. food, for example, they can't get any visuwhile pregnant prefer cereal laced with caral cues about what they're eating. That exUsing the term "chemosensory irritarot juice over cereal made with water. acerbates the decrease in sensory stimulation" to refer to these sensations is unfortion that failing olfaction causes. tunate, says Bruce P. Bryant, a sensory biAt the other end of the spectrum, Moologist and senior research associate at nell associate staff member Marcia Levin Monell. "A small amount of menthol up Pelchat, an experimental psychologist, SIMPLE but effective measures can help your nose or in your mouth or on your skin" works with older people and examines how this segment of the population, Pelchat their chemical senses—especially olfacsays. For example, instead of serving ready- has a cooling effect, he explains. "It is not irritation. Irritation is noxious." tion—are changing as they age and how made bread, communities for the elderly the changes are affecting their nutrition Bryant says a better word is "chemescould prepare bread at the premises to inand quality of life. Most people think that thesis," which is defined as a chemically fuse the dining area with the aroma of bakthe chemical senses uniformly decline with induced sensation that does not involve ing bread. Another is to re-form processed age. Pelchat's work indicates that some taste or odor receptors. Chemesthesis food to familiar shapes: Chicken meat things decline in some people, but not refers to those sensations that result from shaped into a chicken leg provides a better everything, and not in everyone. compounds activating receptor mechavisual cue about the food than does a rannisms for other senses, usually those involved in pain, touch, and thermal perS Y N E R G Y ception. For example, menthol activates receptors that are sensitive to cooling and not really specialized to receive menthol. ake a can of well-chilled carbonated beverage, a glass, and a timer. Pour the bevThe brain interprets signals from those reerage in the glass. Now stick your tongue into the liquid and simultaneously start ceptors as cooling. the timer. How long can you keep your tongue immersed? Like taste and smell, chemesthesis is imThe sharp tingling we feel in the mouth when drinking a carbonated beverage is not portant for survival, Bryant says. "It tells caused by the bubbling of carbon dioxide, as many might think. It is caused by the proyou that something is chemically impingtons produced when carbonic anhydrase acts upon C02. Acidification of nearby nerve ing on your body, that tissue is in immiendings gives rise to the sensation. nent danger. Burrow-dwelling animals can Carbon dioxide also stimulates certain cool-sensitive neurons, and researchers sense toxic levels of carbon dioxide and have found a mutually enhancing interaction between cooling and C02. Thus, at a conpossibly even feel a sting when exposed to stant C02 pressure, a cold soda will feel more pungent than a room-temperature soda. these levels." Conversely, at a constant temperature, a highly carbonated drink will feel cooler than Chemesthesis also vastly expands the one with less carbonation. As Bruce P. Bryant, a senior research associate at the Monsensory experience from food. "Plain ell Chemical Senses Center, says, "You can make a beverage more refreshing just by starch really tastes blah," Bryant says. "But adding carbon dioxide." when you put in chemesthetic stimuli, you Chilling a carbonated beverage enhances the pungency caused by carbonic anhycan alter the perception of the food's therdrase-mediated acidification. On the other hand, the high concentration of C02 in a mal or tactile qualities." freshly opened soda makes a cold soda feel even colder. The mutual enhancement can In trying to understand chemesthesis, make it really painful to keep your tongue in a cold, freshly opened soda for too long. Bryant focuses on neurons and their responses to chemical stimulation. By col-

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laborating with researchers who study hu­ man responses to those chemical stimuli, he is able to relate the cell responses to the human sensation. IN A HUMAN STUDY, volunteers are asked, for example, to rate the intensity of a burn­ ing sensation produced by various com­ pounds. Bryant takes these compounds and, in an in vitro study using neurons known to respond to touch, pain, warming, or cool­ ing, asks: Do these cells respond to the com­ pounds in the same order that the humans rank them? Such studies tell which neurons are important in producing the sensation and whether the compounds can reach the nerve endings in the skin or tongue. One of Bryant's current projects in­ volves Szechuan pepper, a spice used wide­ ly in China, India, Japan, and Nepal. Szechuan pepper contains compounds that produce a vivid sensation that is little known to the Western palate, Bryant says. "On your tongue, these compounds feel like a six-volt battery It's partly electric and partly numbing, and it's totally chemical­ ly induced." The compounds that produce this un­ usual sensation are polyunsaturated alkylamides. Bryant is trying to pinpoint which types of cells are responding to the com­ pounds. He suspects that the compounds are affecting ion channels. Furthermore, Bryant has learned that the sensation caused by polyunsaturated alkylamides may be related to a nervous dysfunction that is manifested as a tingling in the limbs. Understanding what molecular mecha­ nisms respond to these compounds may lead to better understanding of, and per­ haps even treatments for, the malady No one can tell where the basic work on polyunsaturated alkylamides will lead Bryant, but at Monell, he can take it any­ where within the bounds of good sci­ ence, the center's mission, and the cen­ ter's resources. Although Monell addresses many bio­ medical problems, it does not command as much attention as institutions focused on high-profile diseases. Taste and smell dys­ functions and body-odor-production prob­ lems are not in the same league as cancer, for example. But inherently the chemical senses—which are t h e center's raison d'etre—are almost universally interesting. From the chemical stimuli to the biologi­ cal sensors that detect these stimuli, to the processing of the signals and their inter­ pretation in t h e brain, to how these processes converge to affect our well-being and happiness, research at Monell has something for everyone. •

IBC and Sepracor's Third International Symposium on

New Synthetic Methods Chemistry Advancements for Effective Drug Development March 11-13,2002 • The Registry Resort • Naples, FL, USA This extraordinary three-day event continues to draw the world's most esteemed and well-respected chemists working in the field of organic chemistry, and cannot be missed by those wishing to keep abreast of new developments in the field of chemistry. Stellar speakers will present state-ofthe-art catalytic and asymmetric methods, new synthetic technologies for efficient development of drugs, drug candidates, and many versatile synthetic building blocks for numerous chemical processes.

Review the faculty listing below and see why this event is one to add to your calendar as a "Must Attend" Joseph Armstrong, Ph.D.

Kumar G. Gadamasetti, Ph.D.

Prof. William Roush

Roger Bakale, Ph.D.

Charles Johannes, Ph.D.

Chris H. Senanayake, Ph.D.

Prof. Carsten Bolm

Stephen King, Ph.D.

Matthew Sharp, Ph.D.

Prof. Donna Blackmond

Robert Larsen, Ph.D.

Prof. Masakatsu Shibasaki

Stephane Caron, Ph.D.

Michael F. Lipton, Ph.D.

Prof. Mukund Sibi

Prof. Andre Charette

Prof. David W.C. MacMillan

Prof. Marc Snapper

Prof. Michael Doyle

David Mitchell, Ph.D.

Stephen Wittenberger, Ph.D.

Prof. Ben L. Feringa

Richard Polniaszek, Ph.D.

Prof. John L. Wood

View updates, program content and/or to register online:

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