An article published Online First and in an upcoming edition of The Lancet reports that women aged between 24 and 45 can be protected by the human papilloma virus (HPV) vaccine, if they have not been already infected by the virus. The report is the work of Dr Nubia Mu?±oz, from the National Institute of Cancer, Bogot??, Colombia, and collaborators.
Over the last thirty years, sexual behavior has changed. The age of the first marriage is rising, divorce rates are augmenting. As a result, premarital intercourse and having a new sexual partner around middle-age are common behaviors. The HPV virus is transmitted through sexual intercourse and can lead to cervical cancer or other cervical disease. It could be beneficial for older women to receive vaccination against the HPV virus. The women who participated in the randomized trial did not have a history of cervical disease or cancer or genital warts, caused by HPV types 6, 11, 16 and 18. The first group of women received the quadrivalent HPV vaccine and the second group received placebo (at day 1 and months 2 and 6).
There were a total of 1911 women in the first group and 1908 in the second group. The first endpoint for assessment was infection for six months or more, and cervical and external genital disease due to HPV 6, 11, 16, 18. The second was the same but genital disease was due to HPV 16 and 18 only. The average of follow-up time was of 2.2 years. No further data was analyzed at the end of the four year trial. Among the women, specific populations were analyzed.
The per-protocol population of ideal participants included 1615 women who were given the vaccine and 1607 receiving placebo. From day 1 and up to month seven, they all tested negative for the appropriate vaccine HPV type. Within one year, they all had to receive three vaccine doses. They were required to have one or more follow-up visits after month seven. Research showed that there were four cases of infection or disease in the vaccine group compared to forty one in the placebo group. Researchers observed the vaccine proved to have 91 percent effectiveness against all four virus strains (the percent reduction in incidence rate in the vaccine group compared to the placebo group). In the evaluation of the HPV 16 and 18 only, four cases occurred in the vaccine group compared with 23 in the placebo group (vaccine efficiency of 83 percent). When women who had not been completely vaccinated and had already existing HPV infection were included in the analysis, vaccine efficacy against all four HPV types was lower (31 percent). Effectiveness was of 24 percent when it was specifically against types HPV 16 and 18.
The authors write: "Lower effectiveness (about 30%) detected in the mixed population (susceptible women and those who have already acquired HPV infection or HPV-associated disease) suggests that the public health effect of vaccinating women aged 25-45 years will be smaller than that recorded after vaccinating susceptible adolescents. This notion will be assessed in future cost-benefit analyses."
Although there were two target outcomes of the trial, the researchers observed that in general, the women reaching the endpoint had infections, rather than cervical or genital disease. As a result, the high vaccine efficacy in the intention-to-treat population was mostly as a result of efficacy against infection.
The authors explain: "Maximum effect from prophylactic HPV vaccination programmes will be achieved in women who are susceptible to infection and disease related to vaccine HPV types (those not previously exposed). Notably, most adult women enrolled in the current study remained susceptible to vaccine HPV types at entry. Almost all women enrolled were susceptible to three or four vaccine HPV types, and about a third were positive to HPV 6, 11, 16, or 18 at baseline by serological or DNA testing; therefore about two-thirds were susceptible to all four vaccine HPV types. Most women who were HPV positive were positive to only one HPV type, meaning that the quadrivalent HPV vaccine could still potentially benefit these women via protection against vaccine HPV types with which they are not infected with."
They write in conclusion: "The quadrivalent HPV vaccine is efficacious in women aged 24??????"45 years not infected with the relevant HPV types at enrolment."
"Safety, immunogenicity, and efficacy of quadrivalent human papillomavirus (types 6, 11, 16, 18) recombinant vaccine in women aged 24-45 years: a randomised, double-blind trial"
Nubia Mu?±oz, Ricardo Manalastas Jr, Punee Pitisuttithum, Damrong Tresukosol, Joseph Monsonego, Kevin Ault, Christine Clavel, Joaquin Luna, Evan Myers, Sara Hood, Oliver Bautista, Janine Bryan, Frank J Taddeo, Mark T Esser, Scott Vuocolo, Richard M Haupt, Eliav Barr, Alfred Saah
DOI: 10.1016/S0140-6736(09)60691-7
thelancet
Stephanie Brunner (B.A.)
четверг, 12 января 2012 г.
четверг, 5 января 2012 г.
In Postmenopausal Women Height Loss May Indicate Spinal Fracture
Loss of height in postmenopausal women may indicate a vertebral fracture, states an article in CMAJ (Canadian Medical Association Journal).
Height loss is common as people age and is associated with back pain. Causes include changes in the curvature of the spine, narrowing of intervertebral discs and vertebral fractures. Two-thirds of adults have back pain at any time. Diagnosing these treatable disorders, however, sparks controversy because it is not known if the benefits outweigh the harm of unnecessary radiographs.
Researchers from France conducted a study to compare postmenopausal women and analyze reasons for height loss. The study included 1779 randomly selected general practitioners who were each asked to recruit five female patients over the age of 60. A total of 8610 patients were included in the study.
"We observed a mean loss of height of 4.5 cm since early adulthood in a large population of postmenopausal women in primary care practices," write Dr. Karine Briot, H??pital Cochin and Universit?© Paris Descartes, Paris, France and coauthors. "We found that the risk of an existing vertebral fracture was significantly higher among patients with a height loss of at least 4 cm."
The authors conclude that measurement of height loss could be an accurate method for detecting vertebral fractures. Actual height of women was different from what the patients reported. General practitioners need to measure patients and not rely on estimates.
Source:
Kim Barnhardt
Canadian Medical Association Journal
Height loss is common as people age and is associated with back pain. Causes include changes in the curvature of the spine, narrowing of intervertebral discs and vertebral fractures. Two-thirds of adults have back pain at any time. Diagnosing these treatable disorders, however, sparks controversy because it is not known if the benefits outweigh the harm of unnecessary radiographs.
Researchers from France conducted a study to compare postmenopausal women and analyze reasons for height loss. The study included 1779 randomly selected general practitioners who were each asked to recruit five female patients over the age of 60. A total of 8610 patients were included in the study.
"We observed a mean loss of height of 4.5 cm since early adulthood in a large population of postmenopausal women in primary care practices," write Dr. Karine Briot, H??pital Cochin and Universit?© Paris Descartes, Paris, France and coauthors. "We found that the risk of an existing vertebral fracture was significantly higher among patients with a height loss of at least 4 cm."
The authors conclude that measurement of height loss could be an accurate method for detecting vertebral fractures. Actual height of women was different from what the patients reported. General practitioners need to measure patients and not rely on estimates.
Source:
Kim Barnhardt
Canadian Medical Association Journal
четверг, 29 декабря 2011 г.
Majority Of U.S. Residents Support Confirming Supreme Court Nominee Sotomayor, Poll Finds
Sixty-two percent of U.S. residents want Supreme Court nominee Sonia Sotomayor to be confirmed, and 55% say she is "about right" on a liberal-to-conservative scale, according to a recent Washington Post/ABC News poll, the Post reports. For the survey, pollsters randomly surveyed a national sample of 1,001 adults by telephone between June 18 and June 21. The poll has a margin of sampling error of plus or minus three percentage points.
The poll found that about three-fourths of abortion-rights supporters want Sotomayor to be confirmed, compared with less than half of abortion-rights opponents. According to the poll, six in 10 U.S. residents would want the new Supreme Court justice to vote to uphold Roe v. Wade. Most Republican men would want the next Supreme Court justice to vote to overturn Roe, while Republican women were split about evenly on the issue, the poll found.
The poll also found that support for Sotomayor's confirmation was equal between men and women. In addition, nearly eight in 10 Democrats and about two-thirds of independents said they supported Sotomayor's confirmation, compared with 36% of Republicans. The poll found that most Republicans deemed Sotomayor a "more liberal" nominee than they would prefer. Among Republicans, those self-identifying as conservative Republicans were largely opposed to Sotomayor's confirmation, with more than seven in 10 conservative Republicans saying she is too liberal.
Sotomayor received support from Republicans self-identifying as moderate or liberal, with fewer than four in 10 saying she is too liberal. However, about one in five who opposed Sotomayor's confirmation said that she is not liberal enough. The poll also found that among the 33% of U.S. residents who said that Sotomayor's gender plays a role, more than twice as many said that is a positive attribute as opposed to a negative attribute (Cohen/Barnes, Washington Post, 6/28).
Sessions Requests More Information
Senate Judiciary Committee ranking Republican Jeff Sessions (Ala.) on Friday sent a letter to the White House requesting additional information on Sotomayor, the New York Times' "The Caucus" reports. According to Sessions, the Obama administration has yet to provide members of the committee with information about a number of cases that Sotomayor brought to trial while working as a district attorney in New York. In addition, Sessions requested information regarding a case that Sotomayor argued on appeal. He also requested information about her work with Latino Justice PRLDEF, formerly known as the Puerto Rican Legal Defense and Education Fund.
Sotomayor's confirmation hearing is scheduled to begin July 13. Republicans have criticized the schedule, saying it gives them insufficient time to review Sotomayor's record. Democrats have said that Republicans are seeking to create unnecessary delays and noted that the timeline is similar to that of past nominees (Herszenhorn, "The Caucus," New York Times, 6/26).
Reprinted with kind permission from nationalpartnership. You can view the entire Daily Women's Health Policy Report, search the archives, or sign up for email delivery here. The Daily Women's Health Policy Report is a free service of the National Partnership for Women & Families, published by The Advisory Board Company.
© 2009 The Advisory Board Company. All rights reserved.
The poll found that about three-fourths of abortion-rights supporters want Sotomayor to be confirmed, compared with less than half of abortion-rights opponents. According to the poll, six in 10 U.S. residents would want the new Supreme Court justice to vote to uphold Roe v. Wade. Most Republican men would want the next Supreme Court justice to vote to overturn Roe, while Republican women were split about evenly on the issue, the poll found.
The poll also found that support for Sotomayor's confirmation was equal between men and women. In addition, nearly eight in 10 Democrats and about two-thirds of independents said they supported Sotomayor's confirmation, compared with 36% of Republicans. The poll found that most Republicans deemed Sotomayor a "more liberal" nominee than they would prefer. Among Republicans, those self-identifying as conservative Republicans were largely opposed to Sotomayor's confirmation, with more than seven in 10 conservative Republicans saying she is too liberal.
Sotomayor received support from Republicans self-identifying as moderate or liberal, with fewer than four in 10 saying she is too liberal. However, about one in five who opposed Sotomayor's confirmation said that she is not liberal enough. The poll also found that among the 33% of U.S. residents who said that Sotomayor's gender plays a role, more than twice as many said that is a positive attribute as opposed to a negative attribute (Cohen/Barnes, Washington Post, 6/28).
Sessions Requests More Information
Senate Judiciary Committee ranking Republican Jeff Sessions (Ala.) on Friday sent a letter to the White House requesting additional information on Sotomayor, the New York Times' "The Caucus" reports. According to Sessions, the Obama administration has yet to provide members of the committee with information about a number of cases that Sotomayor brought to trial while working as a district attorney in New York. In addition, Sessions requested information regarding a case that Sotomayor argued on appeal. He also requested information about her work with Latino Justice PRLDEF, formerly known as the Puerto Rican Legal Defense and Education Fund.
Sotomayor's confirmation hearing is scheduled to begin July 13. Republicans have criticized the schedule, saying it gives them insufficient time to review Sotomayor's record. Democrats have said that Republicans are seeking to create unnecessary delays and noted that the timeline is similar to that of past nominees (Herszenhorn, "The Caucus," New York Times, 6/26).
Reprinted with kind permission from nationalpartnership. You can view the entire Daily Women's Health Policy Report, search the archives, or sign up for email delivery here. The Daily Women's Health Policy Report is a free service of the National Partnership for Women & Families, published by The Advisory Board Company.
© 2009 The Advisory Board Company. All rights reserved.
четверг, 22 декабря 2011 г.
Green Tea May Protect Against Breast Cancer
While tea has been used as an alternative medicine in China for the last
several thousand years, it is only recently that the Western hemisphere
started to take notice of the beverage??s potential health benefits,
according to University of Southern California researchers. Now, tea is
being hailed as a miracle elixir with the power to do everything from
lower
stress hormones and sooth the symptoms of PMS to protect against disease.
Although many of the claims are unproven, tea has been shown to reduce the
risk of certain kinds of cancer, says Carol Koprowski, Ph.D., R.D.,
assistant professor of preventive medicine at the Keck School of Medicine
of
USC.
??The tea that has been studied the most is green tea,?? she notes. ??It??s
one
of the few teas out there that has been shown to have antioxidants that
may protect against cell damage
Epidemiologist Anna Wu, Ph.D., professor of preventive medicine at the
Keck
School, is studying the relationship between green tea consumption and
breast cancer risk. An earlier study about breast cancer risk among
Asian-American women showed that green tea intake had a strong protective
effect, while the more commonly consumed black tea had no effect at all,
she
says.
While both green and black teas come from the same Camellia sinensis plant
native to Asia, the leaves are processed differently. Black tea leaves go
through a fermentation process that strips the plant of its natural
polyphenol compounds, which are believed to give the tea its antioxidant
properties, Wu says.
Results from a small pilot study suggest that regular green tea drinkers
had
lower blood estrogen levels, while regular black tea drinkers had higher
blood estrogen levels. Higher levels of estrogen are associated with
breast
cancer risk, Wu explains.
While green tea is gaining in popularity around the world in part due to
reports of its disease fighting properties, consumption still lags far
behind black tea in most cultures. Regardless of whether the benefits are
as
widespread as some reports claim, a few cups of either green or black tea
is
a smart addition to a diet as a replacement for high-calorie sodas and
fruit
drinks.
Wu, a life-long black tea drinker, says she hasn??t given it up but now
drinks at least one cup of green tea a day as well.
University of Southern California
usc.edu
several thousand years, it is only recently that the Western hemisphere
started to take notice of the beverage??s potential health benefits,
according to University of Southern California researchers. Now, tea is
being hailed as a miracle elixir with the power to do everything from
lower
stress hormones and sooth the symptoms of PMS to protect against disease.
Although many of the claims are unproven, tea has been shown to reduce the
risk of certain kinds of cancer, says Carol Koprowski, Ph.D., R.D.,
assistant professor of preventive medicine at the Keck School of Medicine
of
USC.
??The tea that has been studied the most is green tea,?? she notes. ??It??s
one
of the few teas out there that has been shown to have antioxidants that
may protect against cell damage
Epidemiologist Anna Wu, Ph.D., professor of preventive medicine at the
Keck
School, is studying the relationship between green tea consumption and
breast cancer risk. An earlier study about breast cancer risk among
Asian-American women showed that green tea intake had a strong protective
effect, while the more commonly consumed black tea had no effect at all,
she
says.
While both green and black teas come from the same Camellia sinensis plant
native to Asia, the leaves are processed differently. Black tea leaves go
through a fermentation process that strips the plant of its natural
polyphenol compounds, which are believed to give the tea its antioxidant
properties, Wu says.
Results from a small pilot study suggest that regular green tea drinkers
had
lower blood estrogen levels, while regular black tea drinkers had higher
blood estrogen levels. Higher levels of estrogen are associated with
breast
cancer risk, Wu explains.
While green tea is gaining in popularity around the world in part due to
reports of its disease fighting properties, consumption still lags far
behind black tea in most cultures. Regardless of whether the benefits are
as
widespread as some reports claim, a few cups of either green or black tea
is
a smart addition to a diet as a replacement for high-calorie sodas and
fruit
drinks.
Wu, a life-long black tea drinker, says she hasn??t given it up but now
drinks at least one cup of green tea a day as well.
University of Southern California
usc.edu
четверг, 15 декабря 2011 г.
New York Times Examines Increasing Scrutiny Of Fertility Industry After Octuplet Birth
The New York Times on Thursday examined how regulators and the fertility industry have begun to view large multiple births as "breakdowns in the system," an issue that has increased debate over how many embryos should be implanted during in vitro fertilization and whether more oversight is warranted. The issue has taken on a renewed focus since the birth of octuplets last month to 33-year-old Nadya Suleman, who has six other children conceived through IVF. According to the Times, nearly one-third of IVF births involve twins or more, and the government and professional medical associations have pushed fertility doctors to lower that number to minimize risks related to multiple births, including infant death, low birth weight, disability and high-cost medical care.
In 2008, the American Society for Reproductive Medicine, an association of fertility doctors, issued guidelines calling for the transfer of no more than two embryos in a woman younger than age 35 and no more than five in women age 35 and older. However, unlike some countries, the U.S. does not enforce the guidelines. The Centers for Disease Control and Prevention collects data on fertility clinic results, but reporting is voluntary. Experts say that many fertility doctors still implant higher numbers of embryos to raise the chances of a pregnancy, the Times reports. The number of triplet births declined from 7% in 1996 to 2% in 2006, a decrease that ASRM considers as one of its successes, according to the Times. However, only 11% of IVF procedures in 2006 involved single embryos, according to CDC data.
The Times reports that efforts to reduce multiple births, such as the guidelines for implanting only one embryo, have caused tension within the fertility industry, a more than $1 billion business. Doctors say patients constantly push for the implantation of multiple embryos. One IVF cycle can cost about $12,000, and "[w]omen who are not successful the first time often try again and again, which can push the cost of having a baby to more than $100,000," the Times reports. The fertility industry in the U.S. has doubled in size since 1996 -- when CDC began tracking data -- and the latest figures show that there are more than 483 clinics and that more than 134,000 procedures have been performed.
Jeffrey Steinberg -- head of Fertility Institutes, a Southern California-based group of fertility clinics -- said, "Every single decision we make about embryo transfers is a tough one, because we don't have a crystal ball." Daniel Potter, medical director of Huntington Reproductive Center in Southern California, said the responsibility of the procedure remains with the doctor, regardless of a patient's requests. He added that if someone came in and wanted to transfer six embryos in a situation" such as Suleman's, then "we have an obligation to protect the patient and not let the patient do things that are unreasonable." Suleman, in an interview on NBC's "Today Show", said that her IVF procedure involved six embryos, and she identified the fertility doctor who performed the procedure as Michael Kamrava of the West Coast IVF Clinic in Beverly Hills, Calif. The Medical Board of California is investigating Kamrava to determine whether there was a violation of standard medical practice. According to the Times, he has "raised eyebrows in the industry" in the past by advocating for a controversial procedure called SEED -- subendometrial embryo delivery, which involves inserting an embryo directly into the uterine lining. Potter said that the procedure's value is not scientifically supported. CDC data from 2006 place Kamrava's clinic among those with the lowest success rates in the country and reveal that the clinic had one of the highest rates of embryos transferred in younger women -- 3.5 embryos versus the average of 2.3 (Saul, New York Times, 2/12).
Reprinted with kind permission from nationalpartnership. You can view the entire Daily Women's Health Policy Report, search the archives, or sign up for email delivery here. The Daily Women's Health Policy Report is a free service of the National Partnership for Women & Families, published by The Advisory Board Company.
© 2009 The Advisory Board Company. All rights reserved.
In 2008, the American Society for Reproductive Medicine, an association of fertility doctors, issued guidelines calling for the transfer of no more than two embryos in a woman younger than age 35 and no more than five in women age 35 and older. However, unlike some countries, the U.S. does not enforce the guidelines. The Centers for Disease Control and Prevention collects data on fertility clinic results, but reporting is voluntary. Experts say that many fertility doctors still implant higher numbers of embryos to raise the chances of a pregnancy, the Times reports. The number of triplet births declined from 7% in 1996 to 2% in 2006, a decrease that ASRM considers as one of its successes, according to the Times. However, only 11% of IVF procedures in 2006 involved single embryos, according to CDC data.
The Times reports that efforts to reduce multiple births, such as the guidelines for implanting only one embryo, have caused tension within the fertility industry, a more than $1 billion business. Doctors say patients constantly push for the implantation of multiple embryos. One IVF cycle can cost about $12,000, and "[w]omen who are not successful the first time often try again and again, which can push the cost of having a baby to more than $100,000," the Times reports. The fertility industry in the U.S. has doubled in size since 1996 -- when CDC began tracking data -- and the latest figures show that there are more than 483 clinics and that more than 134,000 procedures have been performed.
Jeffrey Steinberg -- head of Fertility Institutes, a Southern California-based group of fertility clinics -- said, "Every single decision we make about embryo transfers is a tough one, because we don't have a crystal ball." Daniel Potter, medical director of Huntington Reproductive Center in Southern California, said the responsibility of the procedure remains with the doctor, regardless of a patient's requests. He added that if someone came in and wanted to transfer six embryos in a situation" such as Suleman's, then "we have an obligation to protect the patient and not let the patient do things that are unreasonable." Suleman, in an interview on NBC's "Today Show", said that her IVF procedure involved six embryos, and she identified the fertility doctor who performed the procedure as Michael Kamrava of the West Coast IVF Clinic in Beverly Hills, Calif. The Medical Board of California is investigating Kamrava to determine whether there was a violation of standard medical practice. According to the Times, he has "raised eyebrows in the industry" in the past by advocating for a controversial procedure called SEED -- subendometrial embryo delivery, which involves inserting an embryo directly into the uterine lining. Potter said that the procedure's value is not scientifically supported. CDC data from 2006 place Kamrava's clinic among those with the lowest success rates in the country and reveal that the clinic had one of the highest rates of embryos transferred in younger women -- 3.5 embryos versus the average of 2.3 (Saul, New York Times, 2/12).
Reprinted with kind permission from nationalpartnership. You can view the entire Daily Women's Health Policy Report, search the archives, or sign up for email delivery here. The Daily Women's Health Policy Report is a free service of the National Partnership for Women & Families, published by The Advisory Board Company.
© 2009 The Advisory Board Company. All rights reserved.
четверг, 8 декабря 2011 г.
Gender Differences In Lung Cancer Incidence: Smoke Exposure Alters Gene Expression And Estrogen Metabolism In The Lungs Of Mice
Lung cancer rates are increasing substantially in women, particularly in non-smoking women, with no known reason for the increase. Now researchers at Fox Chase Cancer Center may have uncovered a critical piece in the puzzle.
Working in a mouse model of smoking-induced lung cancer, Margie Clapper, Ph.D., Co-leader of the Cancer Prevention and Control Program at Fox Chase Cancer Center, and colleagues found that smoke triggers rapid changes in gene expression in the lungs of female mice, including increasing expression of a network of genes involved in estrogen metabolism. Based on these data, presented at the 2010 annual meeting of the American Association for Cancer Research, the team hypothesizes that estrogen metabolism may contribute to lung cancer in non-smoking women as well.
Following smoke exposure for 3, 8, or 20 weeks, Sibele Meireles, Ph.D., an assistant member in the Clapper Lab, found that 10 genes were differentially expressed in the lungs of smoke-exposed female mice as compared with control animals. The gene most affected by smoke was cytochrome P450 1b1 (Cyp1b1), which is responsible for breaking down toxins and is a key enzyme for estrogen metabolism. Additionally, when the team looked at networks of genes, they saw that genes involved in estrogen metabolism were altered within the lungs of animals exposed to smoke as compared to controls.
"We found a link between hormones and lung cancer through Cyp1b1 when we weren't looking for it -very exciting," says Clapper. "Previous work has suggested that estrogen may play a role in lung cancer, but no one has shown that smoke can actually accelerate the metabolism of estrogen within the lungs; the suggestion from our data."
The investigators hypothesize that estrogen plays a role in the formation and progression of lung cancers, similar to the role it plays in some breast cancers. The idea is consistent with previous studies indicating that women with lung cancer who take hormone replacement therapy have a poorer prognosis than women who do not, regardless of their smoking history. Additionally the observation that estrogen can be detected within the lungs and that its metabolism is upregulated in the lungs of smoke-exposed female mice may provide new insight into why lung cancer is rising so quickly in women, including non-smoking women world wide, according to Clapper.
The investigators decided to look at gene expression changes after short-term smoke exposure in hopes of finding ways to intervene in or reverse the process. "If we can identify the earliest events that happen within the lungs when you begin to smoke, we might be able to use therapeutics to block them as well as lung cancer," says Clapper, who runs a chemoprevention laboratory at Fox Chase.
First author on the study is Sibele I. Meireles of Fox Chase. Co-authors include Suraj Peri, Karthik Devarajan, Michael Slifker, Stacy L. Mosier, and Jing Peng of Fox Chase, Gustavo H. Esteves of University of Para?ba State, Brazil, Roberto Hirata, Jr., and Jordao Neves of the University of S??o Paulo, Brazil, Manicka V. Vadhanam, Harrell E. Hurst, and Ramesh C. Gupta of the University of Louisville, Kentucky, Luiz F. Reis of the Hospital S?rio Liban??s, Brazil, and C. Gary Gairola of the University of Kentucky in Lexington.
Source:
Diana Quattrone
Fox Chase Cancer Center
Working in a mouse model of smoking-induced lung cancer, Margie Clapper, Ph.D., Co-leader of the Cancer Prevention and Control Program at Fox Chase Cancer Center, and colleagues found that smoke triggers rapid changes in gene expression in the lungs of female mice, including increasing expression of a network of genes involved in estrogen metabolism. Based on these data, presented at the 2010 annual meeting of the American Association for Cancer Research, the team hypothesizes that estrogen metabolism may contribute to lung cancer in non-smoking women as well.
Following smoke exposure for 3, 8, or 20 weeks, Sibele Meireles, Ph.D., an assistant member in the Clapper Lab, found that 10 genes were differentially expressed in the lungs of smoke-exposed female mice as compared with control animals. The gene most affected by smoke was cytochrome P450 1b1 (Cyp1b1), which is responsible for breaking down toxins and is a key enzyme for estrogen metabolism. Additionally, when the team looked at networks of genes, they saw that genes involved in estrogen metabolism were altered within the lungs of animals exposed to smoke as compared to controls.
"We found a link between hormones and lung cancer through Cyp1b1 when we weren't looking for it -very exciting," says Clapper. "Previous work has suggested that estrogen may play a role in lung cancer, but no one has shown that smoke can actually accelerate the metabolism of estrogen within the lungs; the suggestion from our data."
The investigators hypothesize that estrogen plays a role in the formation and progression of lung cancers, similar to the role it plays in some breast cancers. The idea is consistent with previous studies indicating that women with lung cancer who take hormone replacement therapy have a poorer prognosis than women who do not, regardless of their smoking history. Additionally the observation that estrogen can be detected within the lungs and that its metabolism is upregulated in the lungs of smoke-exposed female mice may provide new insight into why lung cancer is rising so quickly in women, including non-smoking women world wide, according to Clapper.
The investigators decided to look at gene expression changes after short-term smoke exposure in hopes of finding ways to intervene in or reverse the process. "If we can identify the earliest events that happen within the lungs when you begin to smoke, we might be able to use therapeutics to block them as well as lung cancer," says Clapper, who runs a chemoprevention laboratory at Fox Chase.
First author on the study is Sibele I. Meireles of Fox Chase. Co-authors include Suraj Peri, Karthik Devarajan, Michael Slifker, Stacy L. Mosier, and Jing Peng of Fox Chase, Gustavo H. Esteves of University of Para?ba State, Brazil, Roberto Hirata, Jr., and Jordao Neves of the University of S??o Paulo, Brazil, Manicka V. Vadhanam, Harrell E. Hurst, and Ramesh C. Gupta of the University of Louisville, Kentucky, Luiz F. Reis of the Hospital S?rio Liban??s, Brazil, and C. Gary Gairola of the University of Kentucky in Lexington.
Source:
Diana Quattrone
Fox Chase Cancer Center
четверг, 1 декабря 2011 г.
Belly Fat Puts Women At Risk For Osteoporosis
For years, it was believed that obese women were at lower risk for developing osteoporosis, and that excess body fat actually protected against bone loss. However, a study presented today at the annual meeting of the Radiological Society of North America (RSNA) found that having too much internal abdominal fat may, in fact, have a damaging effect on bone health.
"We know that obesity is a major public health problem," said the study's lead author, Miriam A. Bredella, M.D., a radiologist at Massachusetts General Hospital and assistant professor of radiology at Harvard Medical School in Boston. "Now we know that abdominal obesity needs to be included as a risk factor for osteoporosis and bone loss."
According to the Centers for Disease Control and Prevention (CDC), approximately 72 million American adults are considered obese. The CDC defines obesity as having a body mass index (BMI) of 30 or more. Obesity is associated with many health problems including cardiovascular diseases, diabetes, high cholesterol, asthma, sleep apnea and joint diseases. Yet despite all the health issues, it was commonly accepted that women with increased body weight were at lower risk for bone loss.
But not all body fat is the same. Subcutaneous fat lies just below the skin, and visceral or intra-abdominal fat is located deep under the muscle tissue in the abdominal cavity. Genetics, diet and exercise are all contributors to the level of visceral fat that is stored in the body. Excess visceral fat is considered particularly dangerous, because in previous studies it has been associated with increased risk for heart disease.
Dr. Bredella and colleagues set out to evaluate the abdominal subcutaneous, visceral and total fat, as well as bone marrow fat and bone mineral density, in 50 premenopausal women with a mean BMI of 30. Each woman underwent an MR spectroscopy exam to evaluate the bone marrow fat of the L4, the fourth vertebra in the lumbar section of the spine. Then, the bone mineral density of the L4 was assessed using quantitative computed tomography (QCT), which measures bone mass and is used to assess bone loss.
The imaging revealed that women with more visceral fat had increased bone marrow fat and decreased bone mineral density. However, there was no significant correlation between either subcutaneous fat or total fat and bone marrow fat or bone mineral density.
"Our results showed that having a lot of belly fat is more detrimental to bone health than having more superficial fat or fat around the hips," Dr. Bredella said.
According to the National Women's Health Information Center, 10 million Americans have osteoporosis and 18 million more have low bone mass, placing them at risk for the disease.
"It is important for the public to be aware that excess belly fat is a risk factor for bone loss, as well as heart disease and diabetes," Dr. Bredella said.
While bone loss is more common in women, the research team is currently conducting a study to determine whether belly fat is also a risk factor for bone loss in men.
Coauthors are Martin Torriani, M.D., Reza Hosseini Ghomi, M.S.E., Bijoy Thomas, M.D., Anne Klibanski, M.D., and Karen Miller, M.D.
Source:
Radiological Society of North America
"We know that obesity is a major public health problem," said the study's lead author, Miriam A. Bredella, M.D., a radiologist at Massachusetts General Hospital and assistant professor of radiology at Harvard Medical School in Boston. "Now we know that abdominal obesity needs to be included as a risk factor for osteoporosis and bone loss."
According to the Centers for Disease Control and Prevention (CDC), approximately 72 million American adults are considered obese. The CDC defines obesity as having a body mass index (BMI) of 30 or more. Obesity is associated with many health problems including cardiovascular diseases, diabetes, high cholesterol, asthma, sleep apnea and joint diseases. Yet despite all the health issues, it was commonly accepted that women with increased body weight were at lower risk for bone loss.
But not all body fat is the same. Subcutaneous fat lies just below the skin, and visceral or intra-abdominal fat is located deep under the muscle tissue in the abdominal cavity. Genetics, diet and exercise are all contributors to the level of visceral fat that is stored in the body. Excess visceral fat is considered particularly dangerous, because in previous studies it has been associated with increased risk for heart disease.
Dr. Bredella and colleagues set out to evaluate the abdominal subcutaneous, visceral and total fat, as well as bone marrow fat and bone mineral density, in 50 premenopausal women with a mean BMI of 30. Each woman underwent an MR spectroscopy exam to evaluate the bone marrow fat of the L4, the fourth vertebra in the lumbar section of the spine. Then, the bone mineral density of the L4 was assessed using quantitative computed tomography (QCT), which measures bone mass and is used to assess bone loss.
The imaging revealed that women with more visceral fat had increased bone marrow fat and decreased bone mineral density. However, there was no significant correlation between either subcutaneous fat or total fat and bone marrow fat or bone mineral density.
"Our results showed that having a lot of belly fat is more detrimental to bone health than having more superficial fat or fat around the hips," Dr. Bredella said.
According to the National Women's Health Information Center, 10 million Americans have osteoporosis and 18 million more have low bone mass, placing them at risk for the disease.
"It is important for the public to be aware that excess belly fat is a risk factor for bone loss, as well as heart disease and diabetes," Dr. Bredella said.
While bone loss is more common in women, the research team is currently conducting a study to determine whether belly fat is also a risk factor for bone loss in men.
Coauthors are Martin Torriani, M.D., Reza Hosseini Ghomi, M.S.E., Bijoy Thomas, M.D., Anne Klibanski, M.D., and Karen Miller, M.D.
Source:
Radiological Society of North America
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