The skull of a juvenile sauropod dinosaur, rediscovered in the collections of Pittsburgh’s Carnegie Museum of Natural History, illustrates that some sauropod species went through drastic changes in skull shape during normal growth.
U-M paleontologists John Whitlock and Jeffrey Wilson, along with Matthew Lamanna from the Carnegie Museum, describe their find in the March issue of the Journal of Vertebrate Paleontology.
The fossil offers a rare chance to look at the early life history of Diplodocus, a 150 million-year-old sauropod from western North America.
“Adult sauropod skulls are rare, but juvenile skulls are even rarer,” says Whitlock, a doctoral candidate in the Museum of Paleontology. “What we do know about the skulls of sauropods like Diplodocus has been based entirely on adults so far.”
“Diplodocus had an unusual skull,” says Wilson, an assistant professor in the Department of Geological Sciences and an assistant curator at the Museum of Paleontology. “Adults had long, square snouts, unlike the rounded or pointed snouts of other sauropods. Up until now, we assumed juveniles did too.”
The small Diplodocus skull, however, suggests that major changes occurred in the skull throughout the animal’s life.
The researchers believe these changes in skull shape may have been tied to feeding behavior, with adults and juveniles eating different foods to avoid competition. Young Diplodocus, with their narrower snouts, may also have been choosier browsers, selecting high quality plant parts.
The discovery also highlights the importance of museum collections for paleontological research.
— Nancy Ross-Flanigan, News Service
Nurses participating in shift work, especially those working rotating shifts, face a significantly increased risk of developing irritable bowel syndrome and abdominal pain compared to those working a standard day-time schedule, according to research published in the American Journal of Gastroenterology.
“We know that people participating in shift work often complain of gastrointestinal symptoms such as abdominal pain, constipation and diarrhea,” says Dr. Sandra Hoogerwerf, assistant professor of internal medicine at the Medical School. “These are the same symptoms of IBS.”
IBS is the most common functional bowel disorder and is difficult to identify because it is diagnosed by clinical symptoms rather than tests, says Hoogerwerf, lead author of the study. IBS symptoms include recurrent episodes of abdominal pain or cramping in connection with altered bowel habits.
Hoogerwerf and her colleagues evaluated nurses classified into three groups — 214 working permanent day shifts, 110 working permanent night shifts and 75 working rotating shifts between day and night — based on self-reported abdominal symptoms and sleep quality. More than 85 percent were women.
“Our findings suggest that nurses participating in shift work, particularly those who participate in rotating shift work, have a higher prevalence of IBS and abdominal pain. This association is independent of sleep quality,” the authors write.
The researchers say their study suggests that sleep disturbances do not completely explain the existence of IBS or abdominal pain associated with shift work.
Additional U-M authors are Dr. Joel Rubenstein, assistant professor of internal medicine at the Medical School; and Dr. William Chey, professor of internal medicine at the Medical School.
— Jenna Frye, UMHS Public Relations
More than one in four elderly Americans lacked the capacity to make their own medical care decisions at the end of life, according to a study of 3,746 people published April 1 in the New England Journal of Medicine.
Those who had advance directives — including living wills or durable powers of attorney for healthcare — received the care they wanted most of the time, says lead author Dr. Maria Silveira, physician scientist at the VA Ann Arbor Healthcare System’s Clinical Management Research and assistant professor of internal medicine.
“Prior to our study, no one knew how many elderly adults might need others to make complex medical decisions on their behalf at the end of life,” Silveira says. “Our research shows that a substantial number of older adults need someone else to make decisions about whether aggressive, limited or comfort care should be provided at the end of life.”
Advance directives usually document patients’ wishes for life-sustaining treatment in a living will, as well as their choice of a proxy decision-maker in a durable power of attorney for health care. Advance directives are sanctioned in all 50 states and can be completed for free without the aid of an attorney.
Co-authoring the study were Dr. Kenneth Langa, a professor in the Department of Internal Medicine, core investigator with VA Ann Arbor Healthcare System’s Clinical Management Research and professor of Health Management and Policy in the School of Public Health; and Dr. Scott Y.H. Kim, associate professor of psychiatry and an investigator in the Bioethics Program and Center for Behavioral and Decision Sciences in Medicine.
— Mary Masson, UMHS Public Relations
Mexican Americans are 40 percent less likely than non-Hispanic whites to call 9-1-1 and be taken to the hospital via ambulance for stroke — resulting in medical treatment delays — according to a new study reported in Stroke: Journal of the American Heart Association.
For the study, researchers used data from the Brain Attack Surveillance in Corpus Christi project to compare hospital arrival time and use of ambulance or emergency medical services by ethnicity, gender and language preference among 1,134 Mexican Americans and non-Hispanic whites who had ischemic strokes between 2000-06.
Subjects were ages 45 years and older; 53 percent Mexican American, 47 percent non-Hispanic white and 52 percent women.
The researchers found that 40 percent of Mexican Americans and 56 percent of whites called 9-1-1 to access EMS. Furthermore, 27 percent of Mexican Americans arrived at the hospital within three hours of stroke symptoms compared with 29 percent of non-Hispanic whites.
“We know calling 9-1-1 is important for getting prompt and appropriate treatment,” says Dr. Lewis Morgenstern, senior study author. “In this study, less than half of people use EMS for stroke. That’s sobering. Everyone should know we have effective treatments for stroke, so they must learn the symptoms and be motivated to call 9-1-1 if they occur.”
Co-authors include Melinda Smith, Lynda Lisabeth and Dr. Frank Bonikowski.
— Shantell Kirkendoll, UMHS Public Relations
Michigan’s local government leaders express an alarming lack of trust in state government leaders in Lansing and significant dissatisfaction with their job performance, a new study shows.
This distrust raises questions about the potential success of state-level policy solutions that depend on local implementation, according to a new Michigan Public Policy Survey by the Center for Local, State, and Urban Policy (CLOSUP).
The survey looked at trust in state government and evaluations of job performance for Gov. Jennifer Granholm and the Michigan Legislature by local government officials statewide.
This study is the first to analyze feedback about state government officials from local leaders representing all types of general purpose local government statewide. Respondents included county administrators and board chairs, mayors and city managers, village presidents and managers and township supervisors, clerks and managers from more than 1,300 jurisdictions statewide.
“These findings illustrate a deeply strained state-local relationship in Michigan,” says Brian Jacob, who heads CLOSUP, which is located in the Gerald R. Ford School of Public Policy, “and may raise concerns about the ability of state-level officials to produce policy solutions that depend on local implementation.”
More than half (53 percent) of local officials give the governor a “poor” job performance rating, although the ratings are strongly tied with political party affiliation. Seventy percent of local officials who are Republican rate the governor’s performance as “poor,” compared to 48 percent of Independent officials and 22 percent of Democratic officials.
Local officials give even lower marks to the Michigan Legislature, with 61 percent grading the performance as “poor” and fewer than 5 percent giving it an “excellent” or “good” rating.
— Jared Wadley, News Service
Gerald Hoff, insurance representative, U-M Health System, on being a diversity advocate: “I don't recall a time or an age in my life when the treatment of others wasn't important to me.”
“Appropriating the Sage: Pictorial Biographies of Confucius from 1444 to the Present” 5 p.m. April 9 in the U-M Museum of Art