Onderdrukken serotonine in darm kan
mogelijk osteoporose genezen
Een medicijn in testfase dat de
serotonine-synthese in de de darm blokkeert, eens per dag oraal toegediend, heeft
effectief osteoporose bij ratten en muizen genezen, volgens een internationaal team geleid
door onderzoekers vande Columbia University Medical Center. in het nummer van 7 feb. van
Nature Medicine. Serotonine in de darmen bleek in recente onderzoeken de botaanmaak tegen
te houden. Deze bevinding zou kunnen leiden tot nieuwe behandelingen voor botaanmaak. De
meeste huidige medicijnen voor osteoporose bieden alleen maar preventie tegen de afbraak
van het bestaande bot. "Nieuwe therapieen die de productie van serotonine in de darm
tegengaan kunnen mogelijk een nieuwe klasse medicijnen vormen die toegevoegd kunnen worden
aan het therapeutische arsenaal tegen osteoporose," aldus Gerard Karsenty, M.D.
PH.D., voorzitter van het Departement van Genetica en Ontwikkeling aan de Columbia
University College voor Artsen en Chirurgen, tevens hoofdauteur van het artikel. "Met
tientallen miljoenen mensen wereldwijd die getroffen worden door dit verwoestende en
verzwakkende botverlies, is er een dringende noodzaak voor nieuwe behandelingen die niet
alleen het botverlies stoppen maar ook nieuw bot aanmaken. Met gebruikmaking van deze
bevindingen werken we hard om dit type behandeling voor menselijke patienten te
ontwikkelen."
Link
Vertaling: Brainiacs
Hartmedicijnen voorkomen geen
gebroken heup
Nitraten, de medicijnen die zorgen dat het
hart meer zuurstof krijgt, beschermen niet tegen een gebroken heup, ondanks aanwijzingen
dat ze de botdichtheid verhogen.
Link
Botmarkers en choline PET-scan
helpen bij opsporing uitgezaaide prostaatkanker
Uit het promotieonderzoek van Anton
Breeuwsma blijkt dat botmarkers in het bloed kunnen helpen bij het voorspellen van de kans
op uitzaaiingen in de botten bij prostaatkanker. Een natrium fluoride-PET scan bleek niet
nauwkeuriger voor het vaststellen van uitzaaiingen in de botten ten opzichte van de
gebruikelijke skeletscan. Overigens lijkt de MRI van het skelet iets nauwkeuriger ten
opzicht van de beide
nucleaire botscans. Met een choline PET scan kan de plaats van opnieuw ontstane
prostaatkanker zichtbaar gemaakt worden, zo blijkt verder. Deze opsporingsmethode is
echter alleen effectief bij patiënten die bestraald zijn. Bij patiënten bij wie de
prostaat operatief is verwijderd, heeft de opsporingsmethode geen meerwaarde bij de keuze
van de vervolgbehandeling boven de gebruikelijke methode.
Link
Gebroken botten en kapotte pezen:
gedachteoefeningen helpen
bij herstel
Patiënten met een spalk om een gekwetst lichaamsdeel, bijvoorbeeld gips om een gebroken
hand of voet, herstellen sneller wanneer zij gedachteoefeningen doen, concludeert
promovendus Martin Stenekes. Stenekes onderzocht de manier waarop het menselijke brein de
handen aanstuurt. Hij concentreerde zich op patiënten die wegens beschadiging aan
buigpezen een tijdlang een spalk aan hun hand hadden. Door zich voor te stellen dat hij
zijn gespalkte hand beweegt, kan de patiënt de aansturing van de hand vanuit de hersenen
op peil houden, zo blijkt uit het onderzoek. Wanneer de spalk verwijderd wordt, hoeft de
patiënt de handbeweging dan minder te oefenen, en herstelt de handfunctie significant
sneller. Het is aannemelijk dat ook patiënten met gipsspalken bij botbreuken en
kneuzingen baat kunnen hebben bij gedachteoefeningen, stelt Stenekes.
Link
Cancer treatment may result in bone
loss
A new cross-Canada study has found that breast and prostate cancer treatment can foster
bone loss. In the online edition of the Journal of Clinical Oncology, the scientists
explain how loss of bone mass might affect 46,000 people diagnosed with breast and
prostate cancer each year* and place them at increased risk for osteoporosis and
fractures. "Our study also looked at possible medications that can reverse or halt
bone loss," says Dr. Fred Saad, lead author and director of urologic oncology at the
Université de Montréal's Faculty of Medicine and the Centre Hospitalier de l'Université
de Montréal (CHUM), who completed the exhaustive study with colleagues from McMaster
University, the Université Laval, the University of Toronto and the University of British
Columbia. "Bone is a dynamic tissue which undergoes a cyclic process of breaking down
and rebuilding," adds Dr. Saad. "Medications called bisphosphonates help with
the rebuilding process and have been successfully used to combat osteoporosis, which is
good news for cancer patients."
Lees verder
Hydrogels Provide Scaffolding For
Growth of Bone Cells
Hyaluronic hydrogels developed by Carnegie Mellon University researchers may provide a
suitable scaffolding to enable bone regeneration. The hydrogels, created by Newell
Washburn, Krzysztof Matyjaszewski and Jeffrey Hollinger, have proven to encourage the
growth of preosteoblast cells, cells that aid the growth and development of bone. Doctoral
student Sidi Bencherif will present this research, Sunday, Aug. 17 at the 236th national
meeting of the American Chemical Society in Philadelphia.Currently, physicians are able to
treat patients with damaged bone tissue, like those who have bone fractures that fail to
heal, using demineralized bone matrix, a biological material obtained from cadavers.
Demineralized bone matrix is rich in growth factor proteins which signal bone cells in the
area to multiply and form complex bone tissue, while other proteins in the matrix regulate
the activity of the growth factors. Demineralized bone matrix is in limited supply, and
because it comes from a human donor, there is a risk of transmitting viruses to the
recipient."Tissue engineering is an exciting field. We're creating solutions to
problems that can significantly impact people's quality of life," said Washburn, an
assistant professor of chemistry and biomedical engineering at Carnegie Mellon.
"These gels have great promise in not only regenerating bone, but serving as a gene
therapy delivery system.
Lees verder
Gene variants associated with
increased risk of bone fractures, low bone mineral density
Results from a large study indicate that variants of the gene LRP5 are associated with a
significant increase in the risk of fractures, by up to 20 percent, and lower levels of
bone mineral density in the spine and hip, according to a study in the March 19 issue of
JAMA, a theme issue on Genetics and Genomics.
Lees verder
Toxins in cigarette smoke prevent
stem cells from becoming cartilage
A toxic pollutant spread by oil spills, forest fires and car exhaust is also present in
cigarette smoke, and may represent a second way in which smoking delays bone healing,
according to research presented today at the annual meeting of the Orthopaedic Research
Society in San Francisco.
Lees verder
New Bone Cement May Prevent
Amputations
Old technologies, bone cement and a well known antibiotic, may effectively fight an
emerging infection in soldiers with compound bone fractures, according to a study
published online today in the Journal of Orthopedic Research. An urgent search for
solutions is underway as 20,000 additional American soldiers head for Afghanistan, and as
evidence emerges that the infection studied may set the stage for more dangerous
infections that can lead to amputation. Osteomyelitis is (OM) a bone infection caused by
various bacteria, and usually occurs in severe fractures when bone is exposed to open air.
Although Acinetobacter baumannii rarely causes OM in the United States, it is very
prevalent in the Middle East, and is now present in more than 30 percent of soldiers
recovering from open fractures in field hospitals in Iraq and Afghanistan. Past studies
have established that one in four severe war wounds in Iraq is a fracture, more than 80
percent of which are open, where the bone is exposed to airborne bacteria.
Lees verder
Paracetamol, one of most used
analgesics, could slow down bone growth
UGR scientists stress the need for controlling the use of paracetamol, as it has been
proved "in vitro" that it slows down bone regeneration. Their work has
demonstrated that applying plasma rich in growth factors, from the patients themselves and
applied on the bones, accelerates cell growth. Therefore, it could also be used to
regenerate wounds or ulcers when applied over soft tissue. Results of this research have
been published in prestigious journals such as Bioscience Reports, Oral Diseases and
Physiology and Biochemistry among others.
Lees verder
Vegan Buddhist nuns have same bone
density as non-vegetarians
A study comparing the bone health of 105 post-menopausal vegan Buddhist nuns and 105
non-vegetarian women, matched in every other physical respect, has produced a surprising
result. Their bone density was identical. The study was led by Professor Tuan Nguyen from
Sydney’s Garvan Institute of Medical Research. He collaborated with Dr Ho-Pham Thuc
Lan from the Pham Ngoc Thach Medical University in Ho Chi Minh City,Vietnam. Their
findings are now published online in Osteoporosis International. “For the 5% of
people in Western countries who choose to be vegetarians, this is very good news,”
saidProfessor Nguyen. “Even vegans, who eat only plant-based foods, appear to have
bones as healthy as everyone else.” “Bone health in vegetarians, particularly
vegans, has been a concern for some time, because as a groupthey tend to have a lower
protein and calcium intake than the population at large.”
Lees
verder
Scientists learn role of oxidative
stress in estrogen-related bone loss
Scientists have discovered new information about an immune pathway in mice that explains
how oxidative stress that results from acute estrogen deficiency leads to the loss of
bone. The finding could help in identifying a new drug target for preventing
postmenopausal bone loss.
Lees verder
Bone fractures can double or triple
mortality for up to 10 years
A new study shows that osteoporotic fractures increase a person’s risk of dying, even
after relatively minor fractures if that person is elderly. With hip fractures, there is
double the risk of death for women, three times the risk for men. The premature mortality
lasts for about 5 years post-fracture, except for hip fractures when it lasts for around
10 years. It then declines towards the background population level. If there’s a
subsequent fracture, mortality risk will rise again for the next 5 years. These facts
underline the importance of preventing and treating osteoporosis, a potentially
devastating condition that affects roughly 2 million Australians. Someone is admitted to
hospital with an osteoporotic fracture every 5-6 minutes, averaging 262 hospitalisations
each day.
Lees
verder
Bicarbonate from fruit and
vegetables may protect bones
Fruit and vegetables produce a chemical called bicarbonate when they're digested.
Researchers have found that bicarbonate supplements help people's bodies retain larger
amounts of calcium, which plays an important part in keeping bones healthy.
Lees
verder
Bone-growing nanomaterial could
improve orthopaedic implants
Bone-forming cells grow faster and produce more calcium on anodized titanium covered in
carbon nanotubes compared with plain anodized titanium and the non-anodized version
currently used in orthopaedic implants, new Brown University research shows. The work,
published in Nanotechnology, uncovers a new material that can be used to make more
successful implants. The research also shows tantalizing promise for an all-new device: a
"smart" implant that can sense and report on bone growth.
Lees
verder
Elderly Women Can Increase Strength
But Still Risk Falls
Elderly women can increase muscle strength as much as young women can, a new study from
the University of New Hampshire finds, indicating that decline in muscle function is less
a natural part of the aging process than due to a decline in physical activity. The
research, published in the journal Medicine & Science in Sports & Exercise,
compared strength gains of inactive elderly women and inactive young women after both
groups participated in an eight-week training regime. Yet while the two groups increased
similar percentages of strength, the older group was far less effective in increasing
power, which is more closely related to preventing falls. "Power is more important
than strength for recovery from loss of balance or walking ability," says Dain
LaRoche, assistant professor of exercise science at UNH and the lead author of the study.
Preventing falls, which occur in 40 percent of people over 65 and are the top reason for
injury-related emergency room visits, is the driving force behind LaRoche's research
agenda. LaRoche compared the initial strength of 25 young (18 - 33) and 24 old (65 - 84)
inactive women then had both groups participate in resistance training on a machine that
targeted knee extensor muscles, which are critical for walking, stair-climbing, or rising
from a chair. "They're what let you live on your own," he says. After eight
weeks of training, the older group not only increased their strength by the same
percentage as the younger group, they achieved gained strength similar to a control group
of young inactive women. But the older group's ability to increase power - force over time
- was significantly less than the younger group's; the elderly women saw only a ten
percent increase in power versus the younger women's 50 percent increase.
Lees verder
From connective tissue to bone
Cartilage, bones and the internal walls of blood vessels can be created by using common
connective tissue cells from human skin. Researchers in reconstructive plastic surgery at
Linköping University have successfully manipulated these tissue cells to take on
different shapes depending on the medium they have been cultivated in.“This means
that it will be much easier to produce autologous tissue, which is tissue created from the
patient’s own body”, says Gunnar Kratz, Professor of Experimental Plastic
Surgery and team leader for the research group.The results of the group’s research
are now published in three simultaneous scientific articles. Bone, cartilage and blood
vessels are important components in reconstructive surgery, where damaged tissue needs to
be recreated. Minor fractures can heal spontaneously but for major bone damage and
cartilage injuries there is the need to transplant tissue from other parts of the
patient’s body. Different strategies have been attempted to instead grow autologous
tissue from stem cells, for example those present in bone marrow. These cells, however,
can be difficult to harvest, cultivate and store. Compared to these cells connective
tissue cells from human skin has great advantages. A small biopsy is often enough to
collect a sufficient amount of cells. “They are the ‘weed’ cells of the
body, very easy to collect and cultivate into the cell type required. They are also very
suitable to use to create a personal cell bank”, Gunnar Kratz says.
Lees verder
Walking prevents bone loss caused
from prostate cancer treatment
Exercise may reduce, and even reverse, bone loss caused by hormone and radiation therapies
used in the treatment of localized prostate cancer, thereby decreasing the potential risk
of bone fractures and improving quality of life for these men, according to a study
presented on Oct. 28, 2007, at the American Society for Therapeutic Radiology and
Oncology's 49th Annual Meeting in Los Angeles.
Lees
verder
A stronger backbone - DHEA hormone
replacement increases bone density in older women
Taking a DHEA supplement combined with vitamin D and calcium can significantly improve
spinal bone density in older women, according to a new study from a Saint Louis University
scientist and his colleagues at Washington University. "The results of our study are
very promising. Similar studies have demonstrated much smaller benefits for bone than we
found. However, calcium and vitamin D deficiencies, which are present in half of older
adults, may have prevented DHEA from improving bone density in the earlier studies,"
said Edward Weiss, Ph.D., associate professor of nutrition and dietetics at Saint Louis
University's Doisy College of Health Sciences and lead author of the study. "In our
study, we supplemented all participants with calcium and vitamin D to ensure that
deficiencies were not present. This may explain why our study showed more favorable
effects on bone density." DHEA (dehydroepiandrosterone), a naturally occurring
steroid hormone produced in the adrenal gland, gonads and brain, decreases with age.
According to Weiss, low DHEA concentration has been associated with low bone density,
which lead researchers to question whether restoring DHEA levels could improve or preserve
bone health. The two-year study divided men and women, ages 65 to 75 years old, into two
groups. The first group received the DHEA supplement, vitamin D and calcium for two years.
The control group received a placebo, vitamin D and calcium for the first year and then
received the DHEA supplement the second year in place of the placebo. The effects of the
treatment differed for men and women. After the first year, women in the test group
experienced an approximate 2 percent increase in bone density, while women in the control
group did not see an increase. After the second year when both groups took the DHEA
supplement, women in the test group experienced an additional 2 percent increase for a
total of approximately 4 percent, while women who switched from placebo to DHEA also
experienced an approximate 2 percent increase. The same treatment, however, did not offer
similar benefits for older men. Instead, men in both the test and control groups
experienced a 1 to 2 percent increase in spinal bone density. According to researchers,
the results suggest that vitamin D and calcium supplements, which were give to both
groups, could be responsible for the increase in bone density.
Lees verder
Discovery provides hope for
sufferers of disfiguring bone disease
Researchers at the University of East Anglia (UEA) have made a major genetic discovery
that could lead to the effective treatment for sufferers of craniosynostosis - a severe
childhood bone disease. Craniosynostosis develops in the womb and affects one in every
2500 live births. Bones in the skulls and face of sufferers fuse together prematurely
causing a range of distressing developmental problems. Some of the affected children also
suffer from defects in the limbs, brain, kidneys and lungs. Depending on the severity of
their disease and its underlying cause, children suffering with craniosynostosis survive
from as little as a few days to as long as early adulthood.
Lees
verder
New tissue scaffold regrows
cartilage and bone
MIT engineers and colleagues have built a new tissue scaffold that can stimulate bone and
cartilage growth when transplanted into the knees and other joints. The scaffold could
offer a potential new treatment for sports injuries and other cartilage damage, such as
arthritis, says Lorna Gibson, the Matoula S. Salapatas Professor of Materials Science and
Engineering and co-leader of the research team with Professor William Bonfield of
Cambridge University. "If someone had a damaged region in the cartilage, you could
remove the cartilage and the bone below it and put our scaffold in the hole," said
Gibson. The researchers describe their scaffold in a recent series of articles in the
Journal of Biomedical Materials Research. The technology has been licensed to
Orthomimetics, a British company launched by one of Gibson's collaborators, Andrew Lynn of
Cambridge University. The company recently started clinical trials in Europe. The scaffold
has two layers, one that mimics bone and one that mimics cartilage. When implanted into a
joint, the scaffold can stimulate mesenchymal stem cells in the bone marrow to produce new
bone and cartilage. The technology is currently limited to small defects, using scaffolds
roughly 8 mm in diameter. The researchers demonstrated the scaffold's effectiveness in a
16-week study involving goats. In that study, the scaffold successfully stimulated bone
and cartilage growth after being implanted in the goats' knees. The project, a
collaboration enabled by the Cambridge-MIT Institute, began when the team decided to build
a scaffold for bone growth. They started with an existing method to produce a skin
scaffold, made of collagen (from bovine tendon) and glycosaminoglycan, a long
polysaccharide chain. To mimic the structure of bone, they developed a technique to
mineralize the collagen scaffold by adding sources of calcium and phosphate.
Lees verder
Building Strong Bones - Running May
Provide More Benefits Than Resistance Training, MU Study Finds
Osteoporosis affects more than 200 million people worldwide and is a serious public health
concern, according to the National Osteoporosis Foundation. Resistance training often is
recommended to increase and prevent loss of bone mineral density (BMD), although previous
studies that examined the effects of resistance training in men produced varied results.
Now, in a new study, University of Missouri researchers have found that high-impact
activities, such as running, might have a greater positive effect on BMD than resistance
training. “The results of the study confirm that both resistance training and
high-impact endurance activities increase bone mineral density. However, high-impact
sports, like running, appear to have a greater beneficial effect,” said Pam Hinton,
associate professor in the Department of Nutrition and Exercise Physiology in the MU
College of Human Environmental Sciences.
Lees
verder
Researchers identify potential
therapeutic target in osteosarcoma
A receptor known to be active in bone metastases, but previously unexplored in primary
bone tumors, is a potential therapeutic target in osteosarcoma, investigators from The
University of Texas M. D. Anderson Cancer Center report in the March 1 issue of Cancer
Research. The researchers found that the protein - interleukin-11 receptor alpha (IL-11Ra)
- is highly expressed in primary osteosarcoma and in lung metastases from these tumors.
Their research suggests the possibility of delivering therapeutic agents directly to
osteosarcoma cells by targeting the receptor with circulating particles that display a
peptide mimic of the natural ligand that binds IL-11Ra. Osteosarcoma is the most common
primary malignant tumor of bone. "Existing treatment has not changed the prognosis
for osteosarcoma for the last 20 to 30 years," said lead investigator Valerae O.
Lewis, M.D., associate professor and chief of Orthopedic Oncology at M. D. Anderson.
"About 30 percent of patients still relapse and die of their disease. New therapeutic
strategies and agents are needed." The effectiveness of the current chemotherapy
regimens for osteosarcoma is limited by toxic side effects, including damage to the heart
and nerves, kidney failure and hearing loss, Lewis noted. Identification of a target
specific for osteosarcoma cells opens the door for the development of therapies that can
shut down the tumor cells without inflicting the collateral damage caused by conventional
osteosarcoma treatments. IL-11Ra is a target in bone metastasis; far less is known about
its attributes, if any, in primary tumors of bone. To address IL-11R? as a potential
molecular target in osteosarcoma, the authors confirmed the protein expression and
localization of IL-11Ra in several mouse and human osteosarcoma cell lines. In an
orthotopic mouse model of human osteosarcoma, the investigators found that the IL-11Ra not
only was markedly present in the primary osteosarcoma and in its metastases but was absent
from normal bone marrow and lungs.
Lees
verder
Bones mend faster without marrow
A new study suggests that removing bone marrow from fractured or broken bone could
encourage new bone growth and speed up recovery. A team in the US drilled into the thigh
bones of rats before syringing out the bone marrow. They found that new bone formed in the
marrow cavity if followed with injections of a drug to encourage bone growth. The study
suggests that bone marrow normally inhibits the formation of new bone.
Lees verder
Genetic disorder sheds light on
enzyme's role in bone metabolism
Pycnodysostosis, a condition from which the painter Henri de Toulouse-Lautrec suffered, is
a genetic disease characterized by short stature. This rare disease, surprisingly,
provides a window into how joints are destroyed by arthritis. It is caused by deficiency
of an enzyme known as cathepsin K which hampers osteoclasts (the cells that break down
bone in bone modeling and repair), leading to poor bone resorption and dense, brittle
bones. Cathepsin K's role in bone metabolism has largely been studied using mouse models,
but a new study examines the enzyme's role in bone resorption in a human patient and shows
that it is not required to break down bone. The study was published in the November issue
of Arthritis & Rheumatism (http://www3.interscience.wiley.com/journal/76509746/home).
Led by Professor Yrjö T. Konttinen of Helsinki University Central Hospital in Helskinki,
Finland , the study involved a 55-year-old female patient with pycnodysostosis who also
developed psoriatic arthritis. Since the patient lacked cathepsin K due to her condition,
researchers hypothesized that this would protect her from the bone erosions in the hands
and feet normally seen in psoriatic arthritis. However, she did in fact develop extensive
erosions and destructive bone changes in her hands. Blood analysis was conducted to
examine the proteinases (enzymes that break down proteins) responsible for bone
degradation as well as the cellular mechanisms of bone resorption. The analyses showed
that the osteoclasts formed by the patient lacked cathepsin K, which was expected.
Surprisingly, however, this deficiency did not prevent cells from resorbing bone, although
the resorption was abnormal. In bone resorption, osteoclasts attach to the bone and
dissolve bone mineral in the matrix, a process that appears to proceed normally even in
pycnodysostosis. In a second step, known as collagenolysis, peptide bonds in the collagen
of the demineralized bone matrix are broken down. The authors expected that this step
would be defective in the cells of a patient who lacked cathepsin K, but instead found
that it was not, since the patient's osteoclasts showed evidence of bone resorption.
Lees verder
Penn Researchers Identify Source of
Cells that Spur Aberrant Bone Growth
Researchers at the University of Pennsylvania School of Medicine and the University of
Connecticut have pinpointed the source of immature cells that spur misplaced bone growth.
Unexpectedly, the major repository of bone-forming cells originates in blood vessels deep
within skeletal muscle and other connective tissues, not from muscle stem cells
themselves. The work also shows that cells important in the inflammatory response to
injury trigger skeleton-stimulating proteins to transform muscle tissue into bone.
Lees
verder
Stem cells could halt osteoporosis,
promote bone growth
While interferon gamma sounds like an outer space weapon, it's actually a hormone produced
by our own bodies, and it holds great promise to repair bones affected by osteoporosis. In
a new study published in the journal Stem Cells, researchers from the Research Institute
of the McGill University Health Centre explain that tweaking a certain group of
multipotent stem cells (called mesenchymal stem cells) with interferon (IFN) gamma may
promote bone growth. "We have identified a new pathway, centered on IFN gamma, that
controls the bone remodelling process both in-vivo and in-vitro," explains Dr.
Kremer, the study's lead author and co-director of the Musculoskeletal Axis of the McGill
University Health Centre. "More studies are required to describe it more precisely,
but we are hopeful that it could lead to a better understanding of the underlying causes
of osteoporosis, as well as to innovative treatments."
Lees verder
Vitamin D halts development of
osteoporosis in people taking antiseizure medications
Supplementing with high levels of vitamin D can help stem the bone loss caused by the
long-term use of antiseizure medication, according to a study published in the journal
Neurology. It has long been known that the antiseizure medications used to control
epilepsy speed up bone breakdown, often leading to bone loss and osteoporosis. It is also
known that vitamin D increases the calcium available to the body for maintaining bone
structure by increasing calcium absorption during digestion and reducing its excretion
through urine.
Lees verder
Popular class of diabetes drugs
doubles risk of fractures in women
New findings out of Wake Forest University School of Medicine and the University of East
Anglia show that long-term use of a popular class of oral diabetic drugs doubles the risk
of fractures in women with type 2 diabetes. The findings appear online today on the Web
site for the Canadian Medical Association Journal and will appear in the January 6 issue.
"We knew going into this study that there was an association between
thiazolidinediones and fracture risk, however the magnitude of risk had not been
evaluated," said Sonal Singh, M.D., M.P.H., an assistant professor of internal
medicine and a co-researcher for the study. "This study shows that these agents
double the risk of fractures in women with type 2 diabetes, who are already at higher risk
before taking the therapy."In absolute terms, Singh said, if thiazolidinediones
(TZDs) are used by elderly, postmenopausal women (around 70 years) with type 2 diabetes
for one year, one additional fracture would occur among every 21 women. Among younger
women (around 56 years), use of the drugs for one year or longer would result in one
additional fracture for every 55 women. TZDs are oral medications given to control
diabetes by lowering blood sugar. The two currently available drugs in this class are
rosiglitazone, marketed as AvandiaTM by GlaxoSmithKline, and pioglitazone, marketed as
ActosTM by Takeda Pharmaceuticals.
Lees verder
Controlling Bone Disease Improves
Survival of Hemodialysis Patients
— Consistently maintaining certain blood levels of markers of bone metabolism and
disease can prolong the lives of patients on hemodialysis, according to a study appearing
in the September 2008 issue of the Clinical Journal of the American Society Nephrology
(CJASN). The findings indicate that keeping parathyroid hormone, calcium, and phosphorous
levels in control is critically important for dialysis patients with chronic kidney
disease (CKD).
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verder
More severe bone infections, health
complications in children linked to MRSA, researchers find
The emergence of methicillin-resistant Staphylococcus aureus as a major pathogen has led
to more complications and longer hospital stays for children with acute bone infections,
UT Southwestern Medical Center researchers report.
Lees
verder
Biomedical researchers create
artificial human bone marrow in a test tube
Artificial bone marrow that can continuously make red and white blood cells has been
created in a University of Michigan lab. This development could lead to simpler
pharmaceutical drug testing, closer study of immune system defects and a continuous supply
of blood for transfusions.
Lees verder
Researchers detail how aging
undermines bone healing
Researchers have unraveled crucial details of how aging causes broken bones to heal
slowly, or not at all, according to study results published today in the Journal of Bone
and Mineral Research. The research team also successfully conducted preclinical tests on a
potential new class of treatments designed to "rescue" healing capability lost
to aging.In the worst cases, an age-related delay in healing keeps the two sides of a
fractured bone from ever rejoining (non-union), leaving many confined to wheelchairs,
unable to walk or to live independently. Of the estimated 5.6 million fractures in the
United States each year, between five and ten percent (up to 560,000) will heal slowly or
incompletely. Researchers have known for 30 years that aging interferes with fracture
healing, and have been filling in the details since on the complex web of biochemicals,
stem cells and genes that bring about healing. The field is now reaching the point where
precision designed drugs are in different stages of animal and human trials.The current
study is focused on cyclooxygenase 2 (COX-2), an enzyme known from past studies to drive
stem cells to differentiate into cartilage, which then matures into bone. Researchers at
the University of Rochester Medical Center 20 years ago discovered the gene in humans that
is responsible for producing the COX-2 enzyme and revealed the enzyme's role in causing
inflammation, the reason drugs like the painkiller Vioxx were developed to shut down its
action. Then about seven years ago another research team here determined that COX-2 also
plays an essential role in bone formation during skeletal repair.
Lees verder
Farming at Young Age May Lead to
Bone Disease in Adulthood
Cincinnati—Although farm chores are likely to keep young boys in shape and out of
trouble, University of Cincinnati (UC) environmental health experts caution that it could
be harmful to overall bone health if done too often at a young age.
Lees verder
Skin cancer fear 'may harm bones'
Worries over skin cancer mean that some people are shunning the sun altogether - which
could endanger their health, a poll has found.
Lees verder
Bone mineral content continues to
increase in obese adolescents during weight loss
Obese teenagers who succeeded in losing weight in a year-long medically supervised weight
control program also saw their bone mineral content increase over that period, say
researchers from The Children's Hospital of Philadelphia. The finding was reassuring,
because adolescence is a critical period for bone health in later life.
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Researchers discover protein that
controls bone growth
A research team led by Dr. Pierre Moffatt of the Shriners Hospital for Children in
Montreal and McGill University's Department of Human Genetics has uncovered the molecular
mechanism by which the protein osteocrin controls bone growth -- a discovery that may have
important implications for people suffering from bone diseases affecting skeletal growth.
The team's findings appear in the Dec. 14 edition of the Journal of Biological Chemistry.
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Proton pump inhibitors increase
risk of bone fractures
Patients who use proton pump inhibitors for seven or more years to treat reflux, peptic
ulcers and other conditions are at greater risk of osteoporosis-related fractures,
according to this large observational study published in CMAJ.
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Bone formation goes with the gut,
study finds
When it comes to remodeling our bones -- an ongoing process of break down and renewal that
goes on throughout adulthood -- researchers have new evidence that our guts play a
surprisingly important role. The findings point toward novel methods for increasing bone
mass in patients with diseases characterized by impaired bone formation, including
postmenopausal osteoporosis, according to the report in the Nov/ 26 issue of the journal
Cell, a Cell Press publication.
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Adiponectin is a metabolic link
between obesity and bone mineral density
Researchers at the University of Toronto, faculty of medicine, Toronto, Canada, have
discovered that adiponectin, a protein secreted from adipocytes, is a metabolic link that
can explain, in part, the known positive relationship between obesity and both bone
mineral density and reduced susceptibility to fractures.
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Exposure to organochlorate
pollutants and lead weakens animals bones, according to a study
A new methodology developed by a researcher of the University of Granada will permit to
determine the toxicological effects caused in animals which have been exposed to
organochlorate pollutants and lead analysing their bones. This work has studied the
effects of lead toxicity in the long term in wild birds populations, determining how this
heavy metal causes bone weakening and fracture, provoking therefore a fall in the
individual survival of the affected species. This work has been carried out by Pedro
Álvarez Lloret, of the Department of Mineralogy and Petrology of the University of
Granada, in collaboration with the University of Georgia (USA), the Karolinska Institute
of Stockholm, the Research Institute for Hunting Resources (CSIC) and the Biological
Station of Doñana (CSIC). The research work has been supervised by Professor Alejandro
Rodríguez Navarro.
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For the first time bone mineral
content can be shown in different anatomical areas of the body
Scientists from the University of Alcalá de Henares (UAH) have examined the patterns of
total bone mineral content of the Spanish population in different areas of the body. The
analysis is the first one of its kind undertaken in Spain that studies subjects from birth
until 80 years of age and confirms the differences in mineral content according to gender
and changes due to age. A team of Spanish researchers set out to establish the reference
values for skeletal bone status in the course of a human being’s lifetime. This is a
“very important piece of work given the changes in bone metabolism of the Spanish
population”, Soledad Aguado, the main author of the work and researcher at the UAH
explains to SINC. The research, published in the latest number of the Skeletal Radiology
Journal, is the first that has been undertaken in Spain in subjects whose ages ranged from
0 to 80 years of age. The study was performed in 1,120 subjects from the Community of
Madrid, all of whom had a sedentary lifestyle. The sample was divided into 16 groups at
5-year age intervals. Each group had a bone densitometry scan using the technique known as
“Dual X-Ray phototonic absorptiometry [DXA]. The aim was to quantify bone mineral
content in the whole body and in different and separate areas of the body. The results
show that there are big differences in gender in the mean values of bone mineral content
for the head and trunk of the body (between 16 and 25 years) and legs and arms (between 16
and 70 years). In all cases, women have less bone mineral content.
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Calcium and vitamin D may not be
the only protection against bone loss
New study finds diet rich in fruits and vegetables may strengthen bones. Chevy Chase,
MD—Diets that are high in protein and cereal grains produce an excess of acid in the
body which may increase calcium excretion and weaken bones, according to a new study
accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology
& Metabolism (JCEM). The study found that increasing the alkali content of the diet,
with a pill or through a diet rich in fruits and vegetables has the opposite effect and
strengthens skeletal health. "Heredity, diet, and other lifestyle factors contribute
to the problem of bone loss and fractures," said Bess Dawson-Hughes, M.D., of Tufts
University in Boston, Mass. and lead author of the study. "When it comes to dietary
concerns regarding bone health, calcium and vitamin D have received the most attention,
but there is increasing evidence that the acid/base balance of the diet is also
important." Average older adults consume diets that, when metabolized, add acid to
the body, said Dr. Dawson-Hughes. With aging, we become less able to excrete the acid. One
way the body may counteract the acid from our diets is through bone resorption, a process
by which bones are broken down to release minerals such as calcium, phosphates, and
alkaline (basic) salts into the blood. Unfortunately, increased bone resorption leads to
declines in bone mass and increases in fracture risk. "When fruits and vegetables are
metabolized they add bicarbonate, an alkaline compound, to the body," said Dr. Dawson
Hughes. "Our study found that bicarbonate had a favorable effect on bone resorption
and calcium excretion. This suggests that increasing the alkali content of the diet may
attenuate bone loss in healthy older adults." In this study, 171 men and women aged
50 and older were randomized to receive placebo or doses of either: potassium bicarbonate,
sodium bicarbonate, or potassium chloride for three months. Researchers found that
subjects taking bicarbonate had significant reductions in calcium excretion, signaling a
decrease in bone resorption. "In this study, we demonstrated that adding alkali in
pill form reduced bone resorption and reduced the losses of calcium in the urine over a
three month period," said Dr. Dawson-Hughes. "This intervention warrants further
investigation as a safe and well tolerated supplement to reduce bone loss and fracture
risk in older men and women."
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Selective restraints and reduced
medication could reduce nursing home falls says 4-year study
Analysis of more than 2,300 falls and fractures at 21 Swedish nursing homes quantifies
increased fall risks from certain drugs and protective effects of selective restraints.
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