The trouble started in 1975 when the predatory rosy wolf snail was introduced deliberately to many South Pacific islands to control an agricultural pest. The rosy wolf snail had a bigger appetite for native land snails than for the pests it was supposed to devour. Over the years, the native snails virtually were wiped out, and today only six of the original 61 species of land snails originally found in the Society Island archipelago survive in the wild.
Researchers and conservationists stepped in during the 1980s and began setting up captive populations in European and North American zoos, and snails from these breeding programs gradually are being reintroduced to protected areas in their former ranges. Understanding the evolutionary relationships between the captive populations, the remaining wild snails and the original species would greatly aid conservation and rehabilitation efforts, says Ó Foighil, and that's where those long-forgotten vials come in.
|Specimen of the Tahitian land snail
Partula otaheitana sampled by J.B. Burch in 1970. (Photo by Gene Lindsay)
In 1970, professor emeritus John (Jack) Burch traveled to Tahiti to study the native snails, which had not yet been decimated by the rosy wolf snail. Hiking deep into valleys where the snails were found, Burch collected several thousand specimens. He shipped about 600 live snails to the University to be freeze-dried. A plan to use the freeze-dried material for a detailed study of evolutionary relationships never materialized, leaving the vials of snails in three wooden trays in a freezer at the Museum of Zoology.
Thanks to a chance conversation with Burch, Ó Foighil learned about the vials. By extracting, amplifying and analyzing DNA from the samples, as well as from snails that die naturally in the zoo collections, Ó Foighil and colleagues can construct evolutionary trees. Some of the information they obtain may help conservationists determine which captive snail populations are best to reintroduce to the wild.
Amid the flood of recent news about America's uninsured, a new study finds a troubling undercurrent: Millions of low-income children's health care gets interrupted because they start the year with one kind of insurance but end it with another kindor they go without any coverage for part of the year.
More than 5.7 million low-income children may experience a transition in their health insurance sometime during each year, the study finds. They may shift to or from being uninsured, or they may join or leave private insurance policies and public programs such as Medicaid, as their family income or situation changes.
The study also finds that low-income kids who experience these changes in their coverage each year are more likely to postpone doctor visits and prescriptions, to go a year without seeing a doctor, or to be in fair or poor health.
The study is the first to show a link between health insurance transitions and child health care trends. It was published in the May issue of Ambulatory Pediatrics by a team from the Child Health Evaluation and Research (CHEAR) Unit of the Medical School's Department of Pediatrics and C.S. Mott Children's Hospital.
"The uninsured in America are not a homogenous group, but a rather mixed group, with some children and families remaining uninsured for a long time and others becoming uninsured more recently, or finding a new source of insurance after being without coverage for some period of time," says senior author and assistant professor Dr. Matthew Davis.
Other authors were Dr. Kimberly Aiken, a clinical instructor of pediatrics who led the analysis during her fellowship; and Dr. Gary Freed, chief of the Division of General Pediatrics and director of the CHEAR unit.
In addition to the many cultural and language issues faced by elderly Arab Americans in the Detroit area, changes in family dynamics have resulted in increased challenges in providing health care and other social services to the group.
That was one of the findings of a survey and set of interviews conducted in 2002-03 by researchers from U-M-Dearborn. Paul Wong, former dean at U-M-Dearborn who now is at San Diego State University, conducted the study with a grant from the federal Administration on Aging, administered by Wayne County Senior Citizens' Services. The project was completed in conjunction with The Senior Alliance-Area Agency on Aging 1-C, which serves the elderly in western and southern Wayne County, and the Arab Community Center for Economic and Social Services (ACCESS).
"All of the respondents had quite a bit to say about changing roles and customs within the Arab American family of today," Wong says. "The biggest change, all agreed, was in the lesser amount of care and time devoted to the elderly due to economic and societal pressures, particularly the employment of women and other family members."
Topping the list of problems faced by Arab and Chaldean elderly in the survey was the problem of language, followed closely by issues connected to cultural differences. Language barriers can result in social isolation and contribute to depression in some cases. Some of the recent immigrants also suffer from depression or post-traumatic stress due to experiences in their countries of origin.
The elderly in the survey indicated a need for transportation more than any other item in the needs-assessment section. Prescription assistance received the second-highest rating of need.
In the years at the dangerous border between adolescence and adulthood, about three men die for every woman, according to a study of the ratio of male to female mortality rates in 20 nations, including the United States.
The study, selected as a "hot topic talk" presented May 28 at the annual meeting of the American Psychological Society, also appears in the current issue of the journal Evolutionary Psychology.
"Being male is now the single largest demographic risk factor for early mortality in developed countries," says Daniel Kruger, lead author of the study and a social psychologist at the Institute for Social Research (ISR). ISR researcher Randolph Nesse, professor of psychiatry at the Medical School, was the co-author of the study.
Funding for the analysis was provided by the National Institute of Mental Health.
In the United States, they found that in the year 2000 males had higher mortality rates than females for 11 causes of death across the lifespan. "The magnitude of the sex difference is most starkly summarized by the numbers of deaths before age 50," Kruger says. "For every 10 premature female deaths, 16 men died prematurely."
The highest male-female mortality ratio for a specific cause was 9.03 for suicide from ages 75 to 79, meaning that nine men in this age range killed themselves for every woman who took her own life. The next highest male-female mortality ratios were for homicide (5.72) and non-automobile accidents (4.91) from ages 20 to 24.
Researchers have developed a new technique for drawing maps that could provide a valuable tool for showing human data such as census findings, election results and disease incidence.
The new technique produces cartogramsmaps in which sizes of areas on the map are in proportion to the population or some other variable, says Mark Newman, assistant professor of physics in LSA. Newman wrote a paper on the technique, which appeared in the May 19 issue of the Proceedings of the National Academy of Sciences, with graduate student and research assistant Michael Gastner.
Making maps of this kind is not a new idea, but until now the methods that existed for drawing cartograms often yielded maps that were difficult to read or that had badly distorted shapes.
Newman and Gastner applied a fundamental physics formula, usually used to solve problems like those associated with gases, to "diffuse" the populations of people in the mapped area. Typically populations are non-uniform, with more people in cities and fewer in outlying areas. Using the formula, they diffused the populations in the mapped area from densely populated areas to less populated areassimilar to the way a gas naturally diffuses in airuntil the population was spread out uniformly. Then they redrew the map with the resulting boundaries. The process is done on a computer, Newman says.
The computer program and the maps it produces provide a useful visualization tool with important scientific applications, such as studies of the geographic distribution of cancer cases.
Pancreatic cancer kills swiftly and surely, and it often goes undiagnosed until it's too late for doctors to provide the only cure: surgery. But new research may give patients a better chance at early detection, firm diagnosis and, someday, better treatment options for the fourth-leading cause of cancer death.
Researchers from the Comprehensive Cancer Center (CCC) last month announced they have found a protein that allows them to tell pancreatic cancer from normal tissue better than the protein used in the current "gold standard" blood test utilized nationwide. They believe this protein, called CEACAM 1, could be used to detect early signs of cancer, especially in those patients at highest risk for the disease.
The same team also reported new findings about the basic cellular processes that allow pancreatic cancer to develop. The discovery of "crosstalk" between two cell signaling pathways involved in the disease may yield clues about why pancreatic tumors develop, and perhaps one day lead to innovative ways to stop them.
Additionally, the researchers reported initial results from gene-based efforts to tell pancreatic cancer from its more common imposter: chronic inflammation of the pancreas, or pancreatitis. By looking at expression levels for three genes in tiny tissue samples removed from patients through a slender needle, they were able to distinguish the two conditions. More research is needed, but the technique could lead to new ways of telling pancreatitis from cancer without the need for surgery.
All three announcements were made at the Digestive Diseases Week meeting in New Orleans. Dr. Diane Simeone's laboratory team made the cell signaling discovery; she co-leads the effort to translate basic genetic research into clinically useful tests, is an associate professor of surgery and runs the CCC's multidisciplinary pancreatic cancer clinic. Researchers also included Craig Logsdon, professor of physiology; postdoctoral fellow Gangyong Li; gastroenterologist Michelle Anderson; Baoan Ji, who presented the CEACAM 1 data; Beth Weinman, James Scheiman, Lizhi Zhang, Vijaya Ramachandran, David Hu, Michael Uhler, Thiruvengadam Arumugam, Samir Hanash, Thomas Giordano, Joel Greenson and Jeremy Taylor.
The research team receives funding from the Michigan Life Sciences Corridor, the Lustgarten Foundation for Pancreatic Cancer Research, CCC and the National Cancer Institute.
Lois Verbrugge takes her research personally. When Verbrugge, an avid swimmer, built a home with her husband on a northern Michigan lake, her scientist's curiosity was piqued by the irritation her skin developed every time she indulged her hobby.
"I started to swim and itched intensely afterward," says Verbrugge, research professor and senior distinguished research scientist at the Institute of Gerontology. "I'm a curious person and started asking questions about what was in the lake."
Out of that was born an article in the May issue of the American Journal of Public Health. Verbrugge examined the incidence and risk factors of swimmer's itchthe lay term for cercarial dermatitiscaused by parasites in the water.
Verbrugge conducted her research at the U-M Biological Station on the shores of Douglas Lake near Pellston. She found that the more days people spent in the water, the more likely they were to develop the painful skin irritation.
Also, time spent in water waist deep or shallower increased likelihood of irritation, as didtime spent in areas of the lake with onshore, or receiving windswinds that blow in toward shore. Onshore winds keep locally produced cercariae in place, and also bring in cercariae produced in other areas, so they become more concentrated.
Verbrugge says it probably is up to individual swimmers to take precautions. She hopes additional epidemiological studies will learn what preventive actions are successful. Verbrugge wears a full Lycra wetsuit to keep the cercariae out of her skin. She never walks through the shallow water near shore, instead walking out to the end of a long dock to get into the lake.