Posted on 08/16/2006 8:25:06 AM PDT by Moonman62
UC Davis researchers today described in unprecedented biochemical and anatomical detail how cigarette smoke damages the lungs of unborn and newborn children.
The findings illustrate with increased urgency the dangers that smokers' families and friends face, said UC Davis Professor Kent Pinkerton, and should give family doctors helpful new insight into the precise hidden physical changes occurring in their young patients' lungs.
"Smoke exposure causes significant damage and lasting consequences in newborns," Pinkerton said. "This research has a message for every parent: Do not smoke or breathe secondhand smoke while you are pregnant. Do not let your children breathe secondhand smoke after they are born."
Pinkerton added that the results from this study are further proof that secondhand smoke's effects on children are not minor, temporary or reversible. "This is the missed message about secondhand smoke and children," he said. "Parents need to understand that these effects will not go away. If children do not grow healthy lungs when they are supposed to, they will likely never recover. The process is not forgiving and the children are not going to be able to make up this loss later in life."
The 2006 Surgeon General's Report on secondhand smoke estimates that more than 126 million residents of the United States age 3 or older are exposed to secondhand smoke. Among children younger than 18 years of age, an estimated 22 percent are exposed to secondhand smoke in their home; estimates range from 11.7 percent in Utah to 34.2 percent in Kentucky.
To get the word out to parents about the dangers of secondhand smoke, two states (Arkansas and Louisiana) have made it illegal to smoke in a car with young passengers. In California, a similar bill, AB 379, is currently under consideration in the state Legislature.
The new UC Davis research is reported in today's issue of the American Journal of Respiratory and Critical Care Medicine. The lead author is Cai-Yun Zhong, a former UC Davis graduate student now working at ArQule Biomedical Institute in Boston; the co-authors are Ya Mei Zhou, also a former UC Davis graduate student and now investigating breast cancer signaling pathways at Buck Research Institute in Novato, Calif.; Jesse Joad, a UC Davis pediatrician who studies children's lung development and cares for sick children in the UC Davis Health System; and Pinkerton, a UC Davis professor of pediatric medicine and director of the UC Davis Center for Health and the Environment.
The Pinkerton research group is one of the few groups in the nation capable of studying the effects of environmental contaminants on unborn and newborn animals. Their 15 years of studies on mice and rats have yielded greater understanding of how air pollution affects human lungs and health through experiments that attempt to reproduce true exposure conditions to environmental air pollutants.
The new study was done with rhesus macaque monkeys, in order to obtain the best possible understanding of what happens in people. Pregnant macaques were exposed to smoke levels equal to those that a pregnant woman would breathe if someone in her home or workplace smoked. Newborn macaques were exposed to secondhand smoke levels similar to those a human baby would breathe if it was cared for by a moderate-to-heavy smoker.
What the researchers found is that environmental tobacco smoke wreaks havoc in babies at a critical time in the development of lungs -- when millions of tiny cells called alveoli (pronounced al-VEE-o-lye) are being formed.
Alveoli are the place where oxygen passes from the lungs into the bloodstream. Human infants are born with only about one-fifth of the 300 million alveoli they will need as adults. They construct almost all those 300 million alveoli between birth and age 8.
Pinkerton's group had previously shown that rats exposed to secondhand smoke while in the womb and after birth developed hyper-reactive, or "ticklish," airways, which typically occurs in children and adults with asthma. The airways in those rodents remained hyper-reactive even when the secondhand smoke exposure stopped. Thus, this early exposure to environmental tobacco smoke created a long-lasting and perhaps permanent asthma-like condition.
In the new study, the researchers analyzed step-by-step how the alveolar cells' inner workings reacted to cigarette smoke. They found the normal orderly process of cell housecleaning had gone haywire.
In healthy people, cells live and die on a schedule. Programmed cell death, called apoptosis (a-pop-TOE-sis), is regulated by genes that increase or decrease various chemical reactions in the cell.
But in this study, when baby monkeys were exposed to cigarette smoke before and after birth, apoptosis went awry. Critical cellular controls regulating cell death turned off. Alveolar cells died twice as fast as they should have.
"If you are killing cells at a higher rate during a critical developmental stage, when they are supposed to be proliferating in order to create new alveoli, the lungs may never be able to recover," Pinkerton said.
Funding for the study, "Environmental Tobacco Smoke Suppresses Nuclear Factor Kappa B Signaling to Increase Apoptosis in Infant Monkey Lungs," was included in a five-year, $1.5 million research grant from the National Institute of Environmental Health Sciences and $450,000 from taxes on sales of tobacco products in California.
Media contact(s): • Kent Pinkerton, Center for Health and the Environment, (530) 752-8334, kepinkerton@ucdavis.edu • Jesse Joad, Department of Pediatrics, (916) 734-3189, jpjoad@ucdavis.edu • Sylvia Wright, UC Davis News Service, (530) 752-7704, swright@ucdavis.edu
"Humans are far more resilient than the "victimization" lobby wants you to believe. After all, our ancestors were reared in smoke filled caves through ice ages....so stop this nonsense and mind your own business, please."
Yeah, and the average lifespan was what? 28 years?
This must present a real dilemma for the moonbats; anti-smoking versus concern for unborn children.
Why would they care if the unborn child is injured by secondhand smoke since they advocate aborting all unborn children anyway?
"I don't have any explanation other than the mother's inhalation being taken in through the lungs to filtrate somehow from their to the fetus' circulatory system, which they share until the umbilicus is severed."
Yes. But the mothers lungs would filter out any effects from the smoke before it is passed through the blood stream to the fetus.
The article is saying that her smoke 'directly effects' the fetus's lungs, which is not possible since the fetus does not breathe air until after it is born.
This study raises more questions than it purports to answer.
How did your dad manage that? Did he smoke several at a time or what?
I think it has something to do with the liver transforming nicotine into a carcinogen and then transferring it to the baby.
Yeah - and died of old age at 35.
It would have to be a chemical effect, perhaps from niicotine.
Second Hand Smoke kills aliens in faraway galaxies.
Yea, our ancestors were burning tobacco leaves to keep warm.... NOT.
Dried wood is not dried tobacco.
I wish to make smoking mandatory.
I agree. (:^*)
Junk Science is real and does no one a service, except perhaps the public funding advocates and the neurotic.
I notice that, as usual, the report is long on conclusions and totally devoid of fact. No methodology. No mention of a control group.
No discussion about the validity of rat physiology as it relates to humans.
No discussion of the mixing of rats and monkeys.
No clue as to what data was encluded from the conclusions or the summary for public consumption.
No mention of the obvious question: How does this study corelate the improvement in newborn lung development with decreased incidence of smoking in the last 40 years.
Do they track?
One would think this would be a validating corelation. For instance, if they track in reverse, it would point to a fatal flaw in the study.
My suspicion is they don't track; thereby the obvious was ignored.
I don't remember how the circulatory system works, but if anything the liver should be the one place that would sort out all the kwap from the baby. I only remember that blood travels unoxygenated until, where, the vena cava? I forget.
Great minds think alike.
Blood-brain barrier?
"Pinkerton's group had previously shown that rats exposed to secondhand smoke while in the womb and after birth developed hyper-reactive, or "ticklish," airways, which typically occurs in children and adults with asthma."
They are saying a 'direct exposure' to the unborns lungs.
Not possible.
Why would 'ticklish' airways develop in an unborn rat?
My mom smoked while she was pregnant with me and I am okay, therefore pregnant women who smoke do not harm their babies.
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