'Chastity belts' block rival sperm in female spiders
12:12 06 March 2007
NewScientist.com news service
Roxanne Khamsi
Some male spiders up-and-leave right after sex for good reason – they risk being eaten by their female partners if they linger too long. In the process of making a swift exit, many leave part of their genitalia inside their mates.
Now a new study reveals that detaching part of the genital organ is not a means to help the male escape a murderous attack. Instead, the abandoned genitals act as "chastity belts" and block the entry of sperm from competitors into the female.
Gabriele Uhl at the University of Bonn, Germany, and colleagues watched wasp spiders (Argiope bruennichi) mate. During the act, a male must insert one of its two sperm-carrying organs, known as pedipalps, into the female’s genital openings. After delivering the sperm, the tip of the pedipalp becomes stuck inside the female, forming a plug in her reproductive tract.
To find out if leaving behind part of the pedipalp helped the males escape death, researchers compared the damage to this organ during first-time sexual encounters with damage sustained in subsequent encounters.
Evolutionary benefit
The experienced males monitored in the experiment had mated once before and only had a single remaining pedipalp intact. These males would enjoy no evolutionary benefit from surviving after mating a second time because they have generally lost both of their pedipalps at this point, and can therefore no longer inseminate females.
According to Uhl, if detaching the pedipalp did offer a survival benefit, one would expect to see it happen more among virgin males, which could mate again, than experienced males, which could not. But the researchers found an equal amount of pedipalp damage among these two groups.
They therefore concluded that detachment of the pedipalp tip cannot significantly enhance a male spider’s chance of escaping attack by his mate.
Uhl’s team also found that a pedipalp tip left inside a female affected how long she copulated for in subsequent encounters. Normally virgin females mate for about 16 seconds, but those with a pedipalp plug mate for only half as long.
This is important because female spiders are more likely to deliver the offspring of those males with which they copulate longest, Uhl says.
She concludes that the pedipalp plug acts as a chastity belt to prevent sperm from competing spiders from entering the females. Uhl's group has also found other types of wasp spiders with a similar "plugging mechanism".
Journal reference: Behavioral Ecology (DOI: 10.1093/beheco/ar1074)
Source URL :http://www.newscientist.com/article/dn11319?DCMP=NLC-nletter&nsref=dn11319
March 09, 2007
March 04, 2007
Save a life by donating your baby's cord blood
BY LAURAN NEERGAARD
Posted Monday, February 26, 2007
Source URL :http://www.dailyherald.com/health/story.asp?id=285342
Flyers in upscale doctors' offices portray it as the hot new baby-shower gift: a registry where friends and family chip in almost $2,000 to start privately banking a newborn's umbilical cord blood, just in case of future illness.
That idea of biological insurance is a long shot that most mothers-to-be can safely ignore, say new guidelines from the nation's pediatricians that urge more parents to donate their babies' cord blood - so that it might save someone's life today.
The guidelines come as the government begins setting up the first national cord-blood banking system, aiming to prevent some 12,000 deaths a year - if public banks can compete with marketing-savvy private companies that now house the bulk of the world's preserved cord blood.
Cord blood is rich in stem cells, the building blocks that produce blood - and the same stem cells that make up the bone-marrow transplants that help many people survive certain cancers and other diseases. But cord blood has some advantages: These younger stem cells are more easily transplanted into unrelated people than bone marrow is, and they can be thawed at a moment's notice, much easier than searching out a bone-marrow donor.
There should be plenty for both private and public banking, says an optimistic Dr. Elizabeth Shpall of the public M.D. Anderson Cord Blood Bank. After all, cord blood from most of the nation's 4 million annual births is thrown away.
Chief hurdles: Improving consumer awareness - and the small number of hospitals that allow donations.
Her own work illustrates the industry's stark socio-economic contrasts: At Houston's Ben Taub General Hospital, Shpall finds the mostly Hispanic mothers-to-be not only unable to afford private banking - few have even heard that cord blood has a medical use.
Armed with a $3 million federal grant to improve much-needed minority donations, she is working with Spanish-language TV and radio programs that in a few months will begin telling Houston moms about their cord blood choices, and which hospitals allow donations.
Her message: "Unless you have a family member with cancer, it's unlikely you would ever need it, and you would be doing a service to humanity to donate it."
Today, about 50,000 cord blood donations are stored in more than 20 public banks around the country. The new National Cord Blood Inventory aims to triple that number, enough that virtually anyone who needs stem cell treatment could find a match - especially minority patients who today seldom can as most bone marrow donors are white.
Private banks have an estimated 400,000 units stored.
What's the controversy? Deciding who really needs to store a child's own cord blood for later use. Private storage costs $1,500 to $1,900 up front, and about $125 a year thereafter, although some offer special programs for lower-income families.
Guidelines published last month by the American Academy of Pediatrics say:
• Parents should consider private storage only if an older sibling has cancer or certain genetic diseases that cord blood is proven to treat.
• Everyone else should consider donating their child's cord blood. The odds that a child would need an infusion of his or her own cord blood later in life are slim, between one in 1,000 and one in 200,000.
Private banks vehemently disagree, arguing that as scientists learn more about stem cells, the blood could create personalized treatments for heart disease or other more common killers.
"That's still considered very experimental," counters Dr. Mitchell Cairo of Columbia University Medical Center, who co-authored the new guidelines.
Also, doctors don't even know if cord blood remains usable after being stored for decades.
Still, last month Illinois doctors reported the first apparent success in treating a child's leukemia with her own cord blood - something usually impossible because that blood so often carries the cancer-triggering genetic defect.
The report has expectant parents calling Advocate Hope Children's Hospital to ask if they, too, should store their babies' cord blood, says Dr. Ammar Hayani, who performed the transplant only after genetic testing showed that patient's cord blood was defect-free.
"It's probably overadvertised by some of these companies as this biological insurance. That's probably overdramatization of its potential," says Hayani, who advises parents of the pediatric academy's guidelines. "But I think parents need to know" both sides' arguments, he says.
About 11 states have recently passed legislation to try to increase the information that expectant parents receive about their cord blood choices: store it, donate it or discard it.
It's no different than how families choose between public or private schools, says Steve Grant of Cord Blood Registry, which began offering the baby-gift option last year after noticing grandparents putting up the money.
"The competitive nature seems misplaced to me," he says. "Family banking is not in any way detracting from the ability to build a public system."
Flyers in upscale doctors' offices portray it as the hot new baby-shower gift: a registry where friends and family chip in almost $2,000 to start privately banking a newborn's umbilical cord blood, just in case of future illness.
That idea of biological insurance is a long shot that most mothers-to-be can safely ignore, say new guidelines from the nation's pediatricians that urge more parents to donate their babies' cord blood - so that it might save someone's life today.
The guidelines come as the government begins setting up the first national cord-blood banking system, aiming to prevent some 12,000 deaths a year - if public banks can compete with marketing-savvy private companies that now house the bulk of the world's preserved cord blood.
Cord blood is rich in stem cells, the building blocks that produce blood - and the same stem cells that make up the bone-marrow transplants that help many people survive certain cancers and other diseases. But cord blood has some advantages: These younger stem cells are more easily transplanted into unrelated people than bone marrow is, and they can be thawed at a moment's notice, much easier than searching out a bone-marrow donor.
There should be plenty for both private and public banking, says an optimistic Dr. Elizabeth Shpall of the public M.D. Anderson Cord Blood Bank. After all, cord blood from most of the nation's 4 million annual births is thrown away.
Chief hurdles: Improving consumer awareness - and the small number of hospitals that allow donations.
Her own work illustrates the industry's stark socio-economic contrasts: At Houston's Ben Taub General Hospital, Shpall finds the mostly Hispanic mothers-to-be not only unable to afford private banking - few have even heard that cord blood has a medical use.
Armed with a $3 million federal grant to improve much-needed minority donations, she is working with Spanish-language TV and radio programs that in a few months will begin telling Houston moms about their cord blood choices, and which hospitals allow donations.
Her message: "Unless you have a family member with cancer, it's unlikely you would ever need it, and you would be doing a service to humanity to donate it."
Today, about 50,000 cord blood donations are stored in more than 20 public banks around the country. The new National Cord Blood Inventory aims to triple that number, enough that virtually anyone who needs stem cell treatment could find a match - especially minority patients who today seldom can as most bone marrow donors are white.
Private banks have an estimated 400,000 units stored.
What's the controversy? Deciding who really needs to store a child's own cord blood for later use. Private storage costs $1,500 to $1,900 up front, and about $125 a year thereafter, although some offer special programs for lower-income families.
Guidelines published last month by the American Academy of Pediatrics say:
• Parents should consider private storage only if an older sibling has cancer or certain genetic diseases that cord blood is proven to treat.
• Everyone else should consider donating their child's cord blood. The odds that a child would need an infusion of his or her own cord blood later in life are slim, between one in 1,000 and one in 200,000.
Private banks vehemently disagree, arguing that as scientists learn more about stem cells, the blood could create personalized treatments for heart disease or other more common killers.
"That's still considered very experimental," counters Dr. Mitchell Cairo of Columbia University Medical Center, who co-authored the new guidelines.
Also, doctors don't even know if cord blood remains usable after being stored for decades.
Still, last month Illinois doctors reported the first apparent success in treating a child's leukemia with her own cord blood - something usually impossible because that blood so often carries the cancer-triggering genetic defect.
The report has expectant parents calling Advocate Hope Children's Hospital to ask if they, too, should store their babies' cord blood, says Dr. Ammar Hayani, who performed the transplant only after genetic testing showed that patient's cord blood was defect-free.
"It's probably overadvertised by some of these companies as this biological insurance. That's probably overdramatization of its potential," says Hayani, who advises parents of the pediatric academy's guidelines. "But I think parents need to know" both sides' arguments, he says.
About 11 states have recently passed legislation to try to increase the information that expectant parents receive about their cord blood choices: store it, donate it or discard it.
It's no different than how families choose between public or private schools, says Steve Grant of Cord Blood Registry, which began offering the baby-gift option last year after noticing grandparents putting up the money.
"The competitive nature seems misplaced to me," he says. "Family banking is not in any way detracting from the ability to build a public system."
Posted Monday, February 26, 2007
Source URL :http://www.dailyherald.com/health/story.asp?id=285342
Flyers in upscale doctors' offices portray it as the hot new baby-shower gift: a registry where friends and family chip in almost $2,000 to start privately banking a newborn's umbilical cord blood, just in case of future illness.
That idea of biological insurance is a long shot that most mothers-to-be can safely ignore, say new guidelines from the nation's pediatricians that urge more parents to donate their babies' cord blood - so that it might save someone's life today.
The guidelines come as the government begins setting up the first national cord-blood banking system, aiming to prevent some 12,000 deaths a year - if public banks can compete with marketing-savvy private companies that now house the bulk of the world's preserved cord blood.
Cord blood is rich in stem cells, the building blocks that produce blood - and the same stem cells that make up the bone-marrow transplants that help many people survive certain cancers and other diseases. But cord blood has some advantages: These younger stem cells are more easily transplanted into unrelated people than bone marrow is, and they can be thawed at a moment's notice, much easier than searching out a bone-marrow donor.
There should be plenty for both private and public banking, says an optimistic Dr. Elizabeth Shpall of the public M.D. Anderson Cord Blood Bank. After all, cord blood from most of the nation's 4 million annual births is thrown away.
Chief hurdles: Improving consumer awareness - and the small number of hospitals that allow donations.
Her own work illustrates the industry's stark socio-economic contrasts: At Houston's Ben Taub General Hospital, Shpall finds the mostly Hispanic mothers-to-be not only unable to afford private banking - few have even heard that cord blood has a medical use.
Armed with a $3 million federal grant to improve much-needed minority donations, she is working with Spanish-language TV and radio programs that in a few months will begin telling Houston moms about their cord blood choices, and which hospitals allow donations.
Her message: "Unless you have a family member with cancer, it's unlikely you would ever need it, and you would be doing a service to humanity to donate it."
Today, about 50,000 cord blood donations are stored in more than 20 public banks around the country. The new National Cord Blood Inventory aims to triple that number, enough that virtually anyone who needs stem cell treatment could find a match - especially minority patients who today seldom can as most bone marrow donors are white.
Private banks have an estimated 400,000 units stored.
What's the controversy? Deciding who really needs to store a child's own cord blood for later use. Private storage costs $1,500 to $1,900 up front, and about $125 a year thereafter, although some offer special programs for lower-income families.
Guidelines published last month by the American Academy of Pediatrics say:
• Parents should consider private storage only if an older sibling has cancer or certain genetic diseases that cord blood is proven to treat.
• Everyone else should consider donating their child's cord blood. The odds that a child would need an infusion of his or her own cord blood later in life are slim, between one in 1,000 and one in 200,000.
Private banks vehemently disagree, arguing that as scientists learn more about stem cells, the blood could create personalized treatments for heart disease or other more common killers.
"That's still considered very experimental," counters Dr. Mitchell Cairo of Columbia University Medical Center, who co-authored the new guidelines.
Also, doctors don't even know if cord blood remains usable after being stored for decades.
Still, last month Illinois doctors reported the first apparent success in treating a child's leukemia with her own cord blood - something usually impossible because that blood so often carries the cancer-triggering genetic defect.
The report has expectant parents calling Advocate Hope Children's Hospital to ask if they, too, should store their babies' cord blood, says Dr. Ammar Hayani, who performed the transplant only after genetic testing showed that patient's cord blood was defect-free.
"It's probably overadvertised by some of these companies as this biological insurance. That's probably overdramatization of its potential," says Hayani, who advises parents of the pediatric academy's guidelines. "But I think parents need to know" both sides' arguments, he says.
About 11 states have recently passed legislation to try to increase the information that expectant parents receive about their cord blood choices: store it, donate it or discard it.
It's no different than how families choose between public or private schools, says Steve Grant of Cord Blood Registry, which began offering the baby-gift option last year after noticing grandparents putting up the money.
"The competitive nature seems misplaced to me," he says. "Family banking is not in any way detracting from the ability to build a public system."
Flyers in upscale doctors' offices portray it as the hot new baby-shower gift: a registry where friends and family chip in almost $2,000 to start privately banking a newborn's umbilical cord blood, just in case of future illness.
That idea of biological insurance is a long shot that most mothers-to-be can safely ignore, say new guidelines from the nation's pediatricians that urge more parents to donate their babies' cord blood - so that it might save someone's life today.
The guidelines come as the government begins setting up the first national cord-blood banking system, aiming to prevent some 12,000 deaths a year - if public banks can compete with marketing-savvy private companies that now house the bulk of the world's preserved cord blood.
Cord blood is rich in stem cells, the building blocks that produce blood - and the same stem cells that make up the bone-marrow transplants that help many people survive certain cancers and other diseases. But cord blood has some advantages: These younger stem cells are more easily transplanted into unrelated people than bone marrow is, and they can be thawed at a moment's notice, much easier than searching out a bone-marrow donor.
There should be plenty for both private and public banking, says an optimistic Dr. Elizabeth Shpall of the public M.D. Anderson Cord Blood Bank. After all, cord blood from most of the nation's 4 million annual births is thrown away.
Chief hurdles: Improving consumer awareness - and the small number of hospitals that allow donations.
Her own work illustrates the industry's stark socio-economic contrasts: At Houston's Ben Taub General Hospital, Shpall finds the mostly Hispanic mothers-to-be not only unable to afford private banking - few have even heard that cord blood has a medical use.
Armed with a $3 million federal grant to improve much-needed minority donations, she is working with Spanish-language TV and radio programs that in a few months will begin telling Houston moms about their cord blood choices, and which hospitals allow donations.
Her message: "Unless you have a family member with cancer, it's unlikely you would ever need it, and you would be doing a service to humanity to donate it."
Today, about 50,000 cord blood donations are stored in more than 20 public banks around the country. The new National Cord Blood Inventory aims to triple that number, enough that virtually anyone who needs stem cell treatment could find a match - especially minority patients who today seldom can as most bone marrow donors are white.
Private banks have an estimated 400,000 units stored.
What's the controversy? Deciding who really needs to store a child's own cord blood for later use. Private storage costs $1,500 to $1,900 up front, and about $125 a year thereafter, although some offer special programs for lower-income families.
Guidelines published last month by the American Academy of Pediatrics say:
• Parents should consider private storage only if an older sibling has cancer or certain genetic diseases that cord blood is proven to treat.
• Everyone else should consider donating their child's cord blood. The odds that a child would need an infusion of his or her own cord blood later in life are slim, between one in 1,000 and one in 200,000.
Private banks vehemently disagree, arguing that as scientists learn more about stem cells, the blood could create personalized treatments for heart disease or other more common killers.
"That's still considered very experimental," counters Dr. Mitchell Cairo of Columbia University Medical Center, who co-authored the new guidelines.
Also, doctors don't even know if cord blood remains usable after being stored for decades.
Still, last month Illinois doctors reported the first apparent success in treating a child's leukemia with her own cord blood - something usually impossible because that blood so often carries the cancer-triggering genetic defect.
The report has expectant parents calling Advocate Hope Children's Hospital to ask if they, too, should store their babies' cord blood, says Dr. Ammar Hayani, who performed the transplant only after genetic testing showed that patient's cord blood was defect-free.
"It's probably overadvertised by some of these companies as this biological insurance. That's probably overdramatization of its potential," says Hayani, who advises parents of the pediatric academy's guidelines. "But I think parents need to know" both sides' arguments, he says.
About 11 states have recently passed legislation to try to increase the information that expectant parents receive about their cord blood choices: store it, donate it or discard it.
It's no different than how families choose between public or private schools, says Steve Grant of Cord Blood Registry, which began offering the baby-gift option last year after noticing grandparents putting up the money.
"The competitive nature seems misplaced to me," he says. "Family banking is not in any way detracting from the ability to build a public system."
March 02, 2007
Taming the wild
Tough GM salmon lose their nerve in the 'wild'
Some genetically modified fish appear to undergo a personality change when they leave laboratory conditions for a more natural environment, according to new research.
Transgenic fish that behave ferociously in a bare tank, appear meek under more natural conditions, meaning it will not be easy for biologists to predict the ecological consequences of escaped GM animals.
Salmon genetically engineered to overproduce growth hormone can put on up to 25 times the weight of wild salmon and could provide "aqua-culturists" with a faster way to raise fish to market size.
However, lab tests suggested that transgenic fish are more aggressive predators than wild salmon, raising concerns that they could harm native fish if they escape into the wild.
Stream tanks
Fredrik Sundström and colleagues at Canada's Center for Aquaculture and Environmental Research, Fisheries and Oceans, in Vancouver, tested whether the GM fish would have the same superiority in more natural conditions.
When they raised the fish in stream tanks complete with gravel, large rocks, logs and natural food items, they found that the GM fish still grew a little faster and ate a little more than unmodified fish, but their advantage was much smaller than when the fish lived in a simple metal tank and ate food in pellet form.
That does not mean escaped GM fish would not cause ecological damage, says Sundström, only that biologists will need to work harder to answer the question. “You can’t use fish reared in the lab to predict what will happen in nature,” he says.
Journal reference: Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0608767104)
February 24, 2007
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