October
2005
Compiled by Linda Abel, MD
Resident, Pfizer Practicum Rotation in Health Policy and
Preventive Medicine
Mechanisms of Late-Onset Cognitive Decline after
Early-Life Stress
Relationship Between Migraine and Stroke
Residential Proximity to Naturally Occurring Asbestos
and Mesothelioma Risk in California
Analysis and Reconstruction of the 1918 Pandemic Flu
Virus
Efficacy of an Acellular Pertussis
Vaccine among Adolescents and Adults
Pillows - a hot bed of fungal spores (October 14, 2005)
Comorbidity and Survival Disparities Among Black and
White Patients With Breast Cancer
Early Mortality Among Medicare Beneficiaries Undergoing
Bariatric Surgical Procedures
Mechanisms of Late-Onset Cognitive Decline after
Early-Life Stress
Progressive cognitive deficits that
emerge with aging are a result of complex
interactions of genetic and environmental
factors. Whereas much has been learned about the genetic
underpinnings of these disorders, the nature
of "acquired" contributing factors, and the
mechanisms by which they promote progressive learning
and memory dysfunction, remain largely unknown.
Here, we demonstrate that a period of
early-life "psychological" stress causes late-onset,
selective deterioration of both complex behavior
and synaptic plasticity: two forms of memory
involving the hippocampus, were severely but
selectively impaired in middle-aged, but not young
adult, rats exposed to fragmented maternal care
during the early postnatal period. At the
cellular level, disturbances to hippocampal
long-term potentiation paralleled the behavioral changes
and were accompanied by dendritic atrophy and
mossy fiber expansion. These findings
constitute the first evidence that a short period
of stress early in life can lead to delayed,
progressive impairments of synaptic and
behavioral measures of hippocampal function,
with potential implications to the basis of age-related
cognitive disorders in humans.
http://www.jneurosci.org/cgi/content/abstract/25/41/9328
The Journal of Neuroscience, October 12, 2005,
25(41):9328-9338; doi:10.1523/JNEUROSCI.2281-05.2005
Kristen L. Brunson,1 Enikö Kramár,2
Bin Lin,2 Yuncai Chen,3 Laura Lee
Colgin,2 Theodore K. Yanagihara,2
Gary Lynch,2 and Tallie Z. Baram1,
October 2005 Index
Relationship Between Migraine and Stroke
A
complex bidirectional relation between migraine, mostly
migraine with aura (MA), and ischemic stroke is known. A
cerebral infarction can occur during a MA, and MA is a
risk factor for ischemic stroke, particularly in young
women. Conversely, cerebral ischemia can induce MA. Both
ischemic stroke and MA might be consequences of many
underlying vascular disorders. Despite the relation
between migraine and stroke, migraine as a primary
headache disorder is mostly benign.
http://www.thelancet.com/journals/laneur/article/PIIS1474442205701642/abstract
Lancet Neurology 2005; 4:533-542,
Marie-Germaine Bowser, Michael Welch
October 2005 Index
Californians
who live close to naturally occurring asbestos sources
and who are exposed to low levels of the mineral are at
increased risk for developing malignant mesothelioma, a
serious cancer of the membrane covering the lung,
according to a new study published in the second issue
of the October 2005 American Thoracic Society's American
Journal of Respiratory and Critical Care Medicine.
Marc B. Schenker, M.D., M.P.H., of the Division of
Environmental and Occupational Health, at the University
of California, Davis, along with four associates,
investigated 2,908 malignant mesothelioma cases reported
over a 10-year period (1988 to 1997). Over 50 percent of
the men and 58 percent of the women, all of whom were
listed in the California Cancer Registry, either had no
or low occupational exposure to asbestos.
“People who lived closer to an asbestos source had a
greater chance of having mesothelioma, and the chance
decreased steadily as the distance increased,” said Dr.
Schenker.
According to the article, the odds of developing
mesothelioma decreased 6.3 percent for every 10
kilometers farther from the asbestos source.
©
2005
American Thoracic Society
American Journal of Respiratory and Critical Care
Medicine
Vol 172. pp. 1019-1025, (2005)
Xue-lei Pan, Howard W. Day, Wei Wang, Laurel A. Beckett
and Marc B. Schenker
October 2005 Index
The
1918 influenza pandemic killed 20–50 million people
worldwide, including many healthy young adults. A
team from the Armed Forces Institute of
Pathology (AFIP) extracted viral RNA from
autopsy specimens of victims and sequenced the viral
genes. As experts have long speculated, the 1918
virus was a true avian flu virus that adapted
to humans. In contrast, the 1957 and 1968 flu
pandemics involved viruses that evolved from
recombination of avian and human viral sequences. The
1918 virus contains several amino acid
changes that also are present in the current
highly pathogenic H5N1 avian virus that has killed
humans in the past 8 years.
Based on the AFIP data, a team at the CDC
recreated the 1918 virus and tested it in
mice for pathogenicity. Compared with
contemporary human flu viruses, the 1918 virus produced
nearly 40,000 times more viral particles in
lung tissue. It caused severe bronchiolitis
and alveolitis, pulmonary edema, and alveolar
hemorrhage — just as it had in human lungs in 1918. By
creating variants of the virus, with changes in
specific genes, the team showed that the
hemagglutinin (HA) gene was essential for
virulence and that the polymerase genes also made
important contributions. Cleavage of the HA
protein, a step critical to pathogenesis,
occurred by a novel mechanism.
By demonstrating parallels between the
1918 flu virus and the current H5N1 avian
virus, these studies increase concern about
the potential effect of another global flu pandemic. At
the same time, this new knowledge, and the ability
to test the pathogenicity of different
experimentally created viral mutants, will
help us identify targets for treatment and vaccination.
Anthony L. Komaroff, MD
Published in
Journal Watch
October 14, 2005
October 2005 Index
Efficacy of an Acellular Pertussis Vaccine among
Adolescents and Adults
In
this randomized trial in subjects between 15 and 65
years old, a new acellular pertussis vaccine
was safe and had an efficacy of 92 percent
against documented, symptomatic Bordetella pertussis
infections. Among controls, the incidence of
pertussis was 370 per 100,000 person-years.
Vaccination of adults and adolescents could
prevent pertussis and reduce the transmission of B.
pertussis to young children.
http://content.nejm.org/cgi/content/short/353/15/1555
Volume 353:1555-1563, October 13, 2005, Number 15Joel
I. Ward, M.D., James D. Cherry, M.D., Swei-Ju Chang,
M.S., Susan Partridge, R.N.,
October 2005 Index
Researchers at The University of
Manchester funded by the Fungal Research Trust have
discovered millions of fungal spores right under our
noses - in our pillows.
Aspergillus fumigatus, the species most
commonly found in the pillows, is most likely to cause
disease; and the resulting condition Aspergillosis has
become the leading infectious cause of death in
leukaemia and bone marrow transplant patients. Fungi
also exacerbate asthma in adults.
The researchers dissected both feather
and synthetic samples and identified several thousand
spores of fungus per gram of used pillow - more than a
million spores per pillow.
http://www.manchester.ac.uk/aboutus/news/pressreleases/pillows/
September 2005, Vol 95, No. 9 | American Journal of
Public Health 1523-1535
© 2005
American Public Health Association
DOI: 10.2105/AJPH.2005.066084
October 2005 Index
Comorbidity and Survival Disparities Among Black and
White Patients With Breast Cancer
Reasons for the shorter survival of black breast
cancer patients compared with their white
counterparts are not completely understood.
The objective of the study was to evaluate the
role of comorbidity in this racial disparity
among breast cancer patients.
The main outcome measures were
breast cancer recurrence/progression and
survival to death from all, breast cancer, and competing
(non–breast cancer) causes. It was
demonstrated that more black breast cancer patients die
of competing causes than of breast cancer.
Effective control of comorbidity in black
breast cancer patients should help improve life
expectancy and lead to a reduction in
survival disparities.
http://jama.ama-assn.org/cgi/content/full/294/14/1765
JAMA. 2005;294:1765-1772.
,C.
Martin Tammemagi, PhD; David Nerenz, PhD; Christine
Neslund-Dudas, MA; Carolyn Feldkamp, PhD; David
Nathanson, MD
October 2005 Index
Early Mortality Among Medicare Beneficiaries Undergoing
Bariatric Surgical Procedures
Previous studies demonstrate that
bariatric surgery can be performed with a low
rate of perioperative mortality (0.5%), but
the rate among high-risk patients and the community
at large is unknown. The objective of
this study was to evaluate the risk of early
mortality among Medicare beneficiaries and to
determine the relative risk of death among
older patients. The study demonstrated that
mmong Medicare beneficiaries, the risk of
early death after bariatric surgery is considerably
higher than previously suggested and
associated with advancing age, male sex, and
lower surgeon volume of bariatric procedures. Patients
aged 65 years or older had a substantially higher
risk of death within the early postoperative
period than younger patients.
http://jama.ama-assn.org/cgi/content/short/294/15/1903
JAMA. 2005;294:1903-1908,
David R. Flum, MD, MPH; Leon Salem, MD; Jo Ann Broeckel
Elrod, PhD; E. Patchen Dellinger, MD; Allen Cheadle,
PhD; Leighton Chan, MD, MPH
October 2005 Index
