Category: Health

Mothers acquiring cells from babies

by philg

She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity by Carl Zimmer:

In 1996, Lee Nelson proposed that microchimerism might make some mothers sick. With half their genetic material coming from their father, fetal cells might be a confusing mix of the foreign and the familiar. Nelson speculated that being exposed to fetal cells for years on end could lead a woman’s immune system to attack her own tissues. That confusion might be the reason that women are more vulnerable to autoimmune diseases such as arthritis and scleroderma. To test this possibility, Nelson and Bianchi collaborated on an experiment. They picked out thrity-three mothers of sons, sixteen of whom were healthy and seventeen of whom suffered from scleroderma. Nelson and Bianchi found that the women with scleroderma had far more fetal cells from their sons than did the healthy women.

But maybe this can be good?

It’s also possible that being a chimera can be good for your health. Bianchi’s first clue that chimerism might have an upside came in the late 1990s, when she was searching for fetal cells in various organs. She discovered a mother’s thyroid gland packed with fetal cells carrying Y chromosomes. Her gland was badly damaged by goiter, and yet it still managed to secrete normal levels of thyroid hormones. The evidence pointed to a startling conclusion: A fetal cell from her son had wended its way through her body to her diseased thyroid gland. It had sensed the damage there and responded by multiplying into new thyroid cells, regenerating the gland.

What about getting genes from a baby that is not genetically one’s own?

As chimerism rises out of the freak category, it also raises unexpected ethical questions. Somewhere around a thousand children a year are born to surrogate mothers in the United States alone. As Ruth Fischbach and John Loike, two bioethicists at Columbia University, have observed, the rules for surrogacy are based on an old-fashioned notion of pregnancy. They treat people as bundles of genes. As a society, we are comfortable with a woman nourishing another couple’s embryo and then parting ways with it, because she does not share the hereditary bond that a biological mother would. If the pregnancy goes smoothly, the surrogate mother is supposed to leave the experience no different than before the procedure. But Fischbach and Loike observed that a surrogate mother and a baby may end up connected in the most profound way possible. Cells from the fetus may embed themselves throughout her body, perhaps for life. And she may bequeath some of her cells to the child. This is not merely a thought experiment. In 2009, researchers at Harvard did a study on eleven surrogate mothers who carried boys but who never had sons of their own. After the women gave birth, the scientists found Y chromosomes in the bloodstreams of five of them.

More: Read She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity

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Human Chimeras

by philg

Some more interesting stuff from She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity by Carl Zimmer… It turns out that Biology 101 contains a lot of simplifications (lies!).

Wikipedia: “A genetic chimerism or chimera … is a single organism composed of cells with distinct genotypes. In animals, this means an individual derived from two or more zygotes, …

How can this happen to a human and how does that interact with our “science is settled” attitude regarding DNA tests? Zimmer gives some examples:

In 2001, a thirty-year-old woman in Germany discovered she was a chimera while she was trying to get pregnant. For the previous five years, she and her husband had been trying to have a baby. They were fairly certain the problem didn’t lie with her biology, because she had gotten pregnant when she was seventeen and had had regular menstrual cycles ever since. A fertility test revealed that her husband had a low level of viable sperm, and so they made plans for IVF. As a routine check, the woman’s doctors took blood samples from her and her husband. They looked at the chromosomes in the couple’s cells, to make sure neither would-be parent had an abnormality that would torpedo the IVF procedure. The woman’s chromosomes looked normal—if she were a man. In every white blood cell they inspected, they found a Y chromosome. Given that she had given birth, this was a weird result. And a careful exam revealed that all her reproductive organs were normal. To get a broader picture of the woman’s cellular makeup, her doctors took samples of her muscle, ovaries, and skin. Unlike her immune cells, none of the cells from these other tissues had a Y chromosome in them. The researchers then carried out a DNA fingerprinting test on the different tissues, looking at the women’s microsatellites—the repeating sequences that can distinguish people from one another. They found that her immune cells belonged to a different person than her other tissues. It turned out that the woman had had a twin brother who died only four days after birth. Although he was unable to survive on his own, his cells took over his sister’s blood and lived on within her.

In 2003, a woman in Washington State named Lydia Fairchild had to get a DNA test. Fairchild, who was then twenty-seven, was pregnant with her fourth child, unemployed, and single. To get welfare benefits, state law required that she prove that her children were genetically related both to herself and to their father, Jamie. One day, Fairchild got a call from the Department of Social Services to come in immediately. A DNA test had confirmed that Jamie was the father of the three children. But Fairchild was not their mother.

When Fairchild was rushed to a hospital to deliver her fourth child, a court officer was there to witness the birth. The officer also oversaw a blood draw for a DNA test. The results came back two weeks later. Once again, Fairchild’s DNA didn’t match her child’s. Even though the court officer had witnessed the child’s birth, the court still refused to consider any evidence beyond DNA.

In Boston, a woman named Karen Keegan had developed kidney disease and needed a transplant. To see if her husband or three sons were a match, her doctors drew blood from the whole family in order to examine a set of immune-system genes called HLA. A nurse called Keegan with the results. Not only were her sons not suitable as organ donors, but the HLA genes from two of them didn’t match hers at all. It was impossible for them to be her children. The hospital went so far as to raise the possibility she had stolen her two sons as babies. Since Keegan’s children were now grown men, she didn’t have to face the terrifying prospect of losing her children as Fairchild did. But Keegan’s doctors were determined to figure out what was going on. Tests on her husband confirmed he was the father of the boys. Her doctors took blood samples from Keegan’s mother and brothers, and collected samples from Keegan’s other tissues, including hair and skin. Years earlier, Keegan had had a nodule removed from her thyroid gland, and it turned out that the hospital had saved it ever since. Her doctors also got hold of a bladder biopsy. Examining all these tissues, Keegan’s doctors found that she was made up of two distinct groups of cells. They could trace her body’s origins along a pair of pedigrees—not to a single ancestral cell but to a pair. They realized Keegan was a tetragametic chimera, the product of two female fraternal twins. The cells of one twin gave rise to all her blood. They also helped give rise to other tissues, as well as to some of her eggs. One of her sons developed from an egg that belonged to the same cell lineage as her blood. Her other two children developed from eggs belonging to the lineage that arose from the other twin. When Lydia Fairchild’s lawyer heard about the Keegan case, he immediately demanded that his client get the same test. At first, it looked as if things were going to go against Fairchild yet again. The DNA in her skin, hair, and saliva failed to match her children’s. But then researchers looked at a sample taken from a cervical smear she had gotten years before. It matched, proving she was a chimera after all.

More: Read She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity

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Why is Roundup still for sale?

by philg

The California legal system has determined that Roundup causes cancer. See, for example, “$2 Billion Verdict Against Monsanto Is Third to Find Roundup Caused Cancer” (nytimes):

The jury, in state court in Alameda County, reached its verdict two months after a federal jury in San Francisco awarded $80 million to a man who claimed that Roundup had caused his non-Hodgkin’s lymphoma. In August, a state court in San Francisco found that Roundup had caused the cancer of a school groundskeeper, awarding him $289 million. A judge reduced that figure to $78 million.

Yet the German owners of Monsanto (safe to assume they wish they’d spent their hard-earned dollars in some other country?) still make the stuff and Amazon still sells it (example). Glyphosate from a variety of manufacturers is available at Home Depot.

How are the retailers immune from liability? If we have faith in our legal system to come up with correct answers to scientific questions, such as “Does glyphosate cause cancer?” then why are millions of Americans apparently still buying and using it?

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Minimal number of approved drugs; fewer approved each year

by philg

Some numbers that I heard at Harvard Medical School:

  • About 1500 compounds that are currently approved as patented or generic drugs.
  • About 500 in clinical trials.
  • About 10 approved every year and declining.

Declining? With half of the new glass towers in Boston and Cambridge packed with biologists and chemists? “It’s getting tougher to approve new drugs because they have to be safe, be effective, and be somehow better for an average population of patients than current drugs,” said my source. “Don’t get me started on the FDA. These criteria are probably too strict. A compound that has bad side effects for one person might affect another person very differently. So it would be good to have more options, especially for those with unusual genetics.”

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Men are not bigger than women; richer Americans are not thinner

by philg

Playing around with R (bleah) and NHANES data (a comprehensive survey of American health and socioeconomic situation; see also this exploration tool at Harvard Medical School), I got a few surprises…

American women actually have a slightly higher average BMI than men. Muscles are supposedly heavier than fat and men are supposedly more muscular, right? This theory is not supported by data. Given two random adults of the same height, the woman will actually be heavier.

One of our fellow residents (might not be a citizen) rang up a BMI of 120(!). Plenty of company in the 50-60 range…

There is almost no correlation between income and BMI. However, the correlation is in an unexpected direction. An increase in income of 6X seems to result in an increase in BMI of about 1. The rich are not thinner. (NHANES may not be a good sample for the truly rich).

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Mediocre U.S. average income makes it tough to reduce health care spending?

by philg

One thing that I learned during a month at Harvard Medical School is that health care spending is inversely correlated with income. The poorer people are, in other words, the more they cost for an insurance company (or the “plan sponsor”, such as an employer, behind the insurance company).

In some cases, of course the causation may go in the other direction, i.e., a person who has a chronic health problem can’t work as hard or as effectively and therefore earns less. But the consensus within the public health and insurance industry seems to be “lower income, therefore higher cost.”

Singapore is notable for low health care spending as a percentage of GDP (only 4.5 percent; compare to 18 percent for the U.S.) while simultaneously enjoying better outcomes, e.g., longer life expectancy. How much of that, though, could be attributed to Singapore simply having a higher-income population? The CIA shows that per-capita GDP, adjusted for purchasing power, in Singapore is $93,900 per person, 58 percent higher than the $59,500 for the U.S. (Singapore and the U.S. are close to each other in rankings of countries by income equality/inequality, so the median incomes should be similarly related).

Plainly this cannot explain most of our off-the-charts spending on health care. Canada and the big European countries spend much less, as a percentage of GDP, despite having lower per-capita income. But if we assume constant waste due to our more-or-less constant system design (fee-for-service, half government, patient doesn’t pay directly), the stagnant U.S. median income (FRED data) could perhaps explain some of why it is so tough for us to achieve incremental improvements.

The “U.S. population” is a moving target, especially due to immigration. Immigrants have a lower income than native-born Americans (see data below), but they also change the median age of the population, which is a big determinant of health care costs (older people are more expensive): “Without immigration since 1965, the U.S. today would have a median age of 41, not 38.” (Pew). Our incompetence at delivering health care may be masked to some extent by immigration, which has reduced median age. Also complicating matters is that immigrants may be less likely than average to have some chronic medical issues. A morbidly obese person, for example, might have trouble making it over the border.

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American health insurance fine print: wait one extra day for surgery after an accident and price goes up dramatically

by philg

Here’s a fun story on the health insurance system that America’s most brilliant technocrats have created…

Woman falls on Christmas (Tuesday) morning and breaks her collarbone. Blue Cross pays 100 percent of the cost of emergency care following an accident. $0 deductible. ED doc says will likely heal on its own. First available consult with an orthopedic specialist is Thursday morning. After a bit of deliberation, it is decided that surgery to insert a plate may be helpful. This will cost the insurer $30,942 ($35,080 “rack rate”). Had it been completed within 72 hours of the emergency visit, it would have been covered completely. Due in part to the holiday and a question about whether the break could heal adequately on its own, the surgery was not done until the following Monday, outside of the 72-hour window (one business day beyond, or maybe not even that if we subtract out Christmas).

Although the procedure is exactly the same, now the insurance customer must pay 15 percent of the total: nearly $5,000!

So the insurance company that you might think would want to encourage patients to step back and consider whether an offered intervention is useful instead gives them a huge financial incentive to sign up for whatever physicians put on the menu during the first 72 hours!

(The good news is that any customer who memorizes the 165-page 2018 benefits document would be well aware of this 72-hour cliff (don’t forget to read the 176-page PDF for 2019, though!).)

Related:

  • “A $20,243 bike crash: Zuckerberg hospital’s aggressive tactics leave patients with big bills” (Vox), in which the government-run hospital tries to get $24,074 for a $3,831 (market price) visit because “the hospital’s focus is on serving those with public health coverage — even if that means offsetting those costs with high bills for the privately insured. … ‘Our mission is to serve people who are underserved because of their financial needs.'” (the woman involved in the bike accident never had a choice to go to a hospital that was in-network for her Blue Cross)
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Healthy cannabis becomes poisonous marijuana at an elementary school

by philg

“At least a dozen elementary students exposed to marijuana gummies, police say; mom arrested” (CNN, 2019):

More than a dozen students at an elementary school in Cleveland were admitted to the hospital after being exposed to gummy candy that police say contained marijuana.

Fifteen children, ages 5 to 9, were tested for drugs and released from Rainbow Babies & Children’s Hospital at University Hospitals Ahuja Medical Center, said Katelyn McCarthy, a media relations strategist at the hospital.
She said that a couple of the children complained of stomachaches.
The police report noted that one of the children tested positive for a mind-altering chemical found in marijuana called tetrahydrocannabinol, also known as THC.

“When young children consume them, they can result in severe symptoms, including dizziness, excessive sleepiness and, in rare circumstances, impair their breathing,” [the toxicologist] said.

It’s key to safely store marijuana products far from where children can see them, said Dr. Suzan Mazor, director of toxicology for Seattle Children’s Hospital and a toxicology consultant for the Washington Poison Center, who was not involved in the Cleveland case.

Also, “make sure to have the poison center phone number on hand for caretakers, grandparents: 1-800-222-1222,” said Mazor, who is also an associate professor of pediatrics and emergency medicine at the University of Washington School of Medicine.

Previously in CNN:

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