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brdgt
I confess: I swallow gum and seeds. Am I lazy? Suicidal? At least it's safe...
Really? The Claim: Swallowed Gum Takes a Long Time to Digest
By ANAHAD O’CONNOR, The New York Times, August 28, 2007
THE FACTS
For generations, parents have told their children never to swallow chewing gum, lest it sit undigested for days, weeks or even years.
This is, for the most part, an old wives’ tale. Swallowed chewing gum typically passes through the digestive tract without harm and is eliminated at the same rate as other foods.
But rare complications can occur. The medical literature contains several case reports of people, mostly small children, who developed intestinal obstructions because they had a habit of swallowing their gum. A 1998 study in the journal Pediatrics, for example, described three children who came to a clinic with intestinal pain, constipation and other symptoms, and were found to have small masses of chewing gum in their guts. One was a 4-year-old boy who “always swallowed his gum after chewing five to seven pieces each day.” Another was a 4-year-old girl.
Three other studies, including one in The American Journal of Diseases of Children, describe similar cases. In most, the young patients were fine after removal of the obstructions. The phenomenon is rare, the studies noted. But they might also serve as a cautionary tale for the parents of small children, particularly those with a strong fondness for gum.
THE BOTTOM LINE
Chewing gum is typically digested without harm, though rare complications can occur.
All I could think when I saw this story was that those doctors are not wearing nearly enough protection while handling bats who could potentially have Marburg. This is a disease where "not as bad as ____" doesn't really apply, because not being as bad as Ebola is small consolation. It is pretty big news to have confirmation of the animal reservoir, however.
At a mine in Uganda, left and center, bats are being captured and tested by doctors from the Centers for Disease Control and Prevention, right. International health groups are jointly studying whether the bats harbor the Marburg virus.
Venturing Into the Mines of Uganda, in Search of the Marburg Virus
By NICHOLAS BAKALAR, The New York Times, August 28, 2007
Researchers reported for the first time last week that they have found the Marburg virus in a nonprimate species — bats.
Now, they have turned their attention to a bat-infested lead and gold mine in western Uganda, in an attempt to determine if bats harbor the disease between periodic outbreaks in southern Africa. One miner working in the mine died of Marburg disease on July 14, and several others apparently recovered from it. “We’re trying to see where this goes,” Jonathan Towner, the lead author of the report, published Aug. 22 in the online journal PloS ONE, said in a telephone interview. “We need a good, solid survey of what’s living here and what might have Marburg in it.”
Dr. Towner, a microbiologist with the Centers for Disease Control and Prevention, is working in Ibanda, Uganda, with a group jointly sponsored by the agency, the World Health Organization and the National Institute of Communicable Diseases, a South African government group.
Because Ebola, a closely related virus, had earlier been found in bats, scientists suspected they might harbor Marburg as well. The scientists tested more than 1,100 bats of 10 species in Gabon and Congo and found the virus in four bats of the cave-dwelling species, Rousettus aegyptiacus. The bats, which range all over sub-Saharan Africa, had been trapped in 2005 and 2006 at two locations in Gabon. All of the infected animals appeared healthy.
Marburg infection in humans can be fatal. Symptoms include persistent diarrhea, high fever, bleeding from the nose, gums and vagina, and bloody vomit and feces. There have been periodic occurrences of Marburg in southern Africa during the past three decades, but no one has been able to figure out its natural reservoir — that is, where the virus hides between outbreaks.
If the researchers can confirm that the bat is the reservoir of the virus, the next question is what to do about it. “The knee-jerk reaction is to exterminate all of the bats in the mine,” Dr. Towner said. “But ecologically, that’s a bad thing to do because bats pollinate plants and eat harmful insects by the ton.”
Teaching people how to protect themselves, he continued, may be a better approach. “Wear gloves, hats, masks, and respirators and be mindful of what you stick your hands in,” he said. “And leave the bats alone.”
And while I'm scaring you...
Mite harvestmen, relatives of daddy longlegs, have a typical range of less than 50 miles, and they cannot disperse well.
A Daddy Longlegs Tells the Story of the Continents’ Big Shifts
By CARL ZIMMER, The New York Times, August 28, 2007
Few people have heard of the mite harvestman, and fewer still would recognize it at close range. The animal is a relative of the far more familiar daddy longlegs. But its legs are stubby rather than long, and its body is only as big as a sesame seed.
To find mite harvestmen, scientists go to dark, humid forests and sift through the leaf litter. The animals respond by turning motionless, making them impossible for even a trained eye to pick out. “They look like grains of dirt,” said Gonzalo Giribet, an invertebrate biologist at Harvard.
As frustrating as mite harvestmen may be, Dr. Giribet and his colleagues have spent six years searching for them on five continents. The animals have an extraordinary story to tell: they carry a record of hundreds of millions of years of geological history, chronicling the journeys that continents have made around the Earth.
The Earth’s land masses have slowly collided and broken apart again several times, carrying animals and plants with them. These species have provided clues to the continents’ paths.
The notion of continent drift originally came from such clues. In 1911, the German scientist Alfred Wegner was struck by the fact that fossils of similar animals and plants could be found on either side of the Atlantic. The ocean was too far for the species to have traveled themselves. Wegner speculated — correctly, as it turned out — that the surrounding continents had originally been welded together in a single landmass, which he called Pangea.
Continental drift, or plate tectonics as it is scientifically known, helped move species around the world. Armadillos and their relatives are found in South America and Africa today because their ancestors evolved when the continents were joined. When South America and North America connected a few million years ago, armadillos spread north, too.
Biogeographers can learn clues about this history by comparing related species. To do so, they must also recognize cases where species crossed great stretches of water.
The island of Hawaii, for example, was home to a giant flightless goose that has become extinct. Studies on DNA extracted from its bones show that it evolved from the Canada goose.
Based on its DNA, scientists estimated that the giant goose branched off from Canada geese half a million years ago. That is also when geologists estimate that Hawaii emerged from the Pacific.
When species jump around the planet, their histories blur. It is difficult to say much about where cockroaches evolved, for example, because they can move quickly from continent to continent. This process, known as dispersal, limits many studies.
“Most of them tend to concentrate on particular parts of the world,” Dr. Giribet said. “I wanted to find a new system for studying biogeography at a global scale.”
Dr. Giribet realized that mite harvestman might be that system. The 5,000 or so mite harvestmen species can be found on every continent except Antarctica. Unlike animals found around the world like cockroaches, mite harvestmen cannot disperse well. The typical harvestman species has a range of less than 50 miles. Harvestman are not found on young islands like Hawaii.
“It’s really hard to find a group of species that is distributed all over the world but that also don’t disperse very far,” said Sarah Boyer, a former student of Dr. Giribet, now an assistant professor at Macalester College in St. Paul.
What mite harvestmen lack in mobility, they make up in age. Their ancestors were among the first land animals, and daddy longlegs fossils have been found in 400 million-year-old rocks. Mite harvestmen evolved long before Pangea broke up and have been carried along by continental drift ever since.
“They’ve managed to get themselves around the world only because they’ve been around for hundreds of millions of years,” Dr. Boyer said.
Dr. Boyer, Dr. Giribet and their colleagues set off around the world to collect a diverse group of mite harvestmen. They ended up gathering thousands of animals from which they extracted DNA.
The gene variations helped the scientists build an evolutionary tree. By calculating how quickly the DNA mutated, the scientists could estimate when lineages branched off. They then compared the harvestmen evolution to the movements of the continents.
“The patterns are remarkably clear,” Dr. Boyer said.
She, Dr. Giribet and colleagues are publishing their results papers to appear in The Journal of Biogeography, Cladistics and other journals.
The scientists found that they could trace mite harvestmen from their ancestors on Pangea. One lineage includes species in Chile, South Africa, Sri Lanka and other places separated by thousands of miles of ocean. But 150 million years ago, all those sites were in the same region of southern Pangea, Gondwana.
The harvestmen preserve smaller patterns of continental drift, as well as bigger ones. After analyzing the DNA of a Florida harvestman, Metasiro americanus, the scientists found that it was not related to other North American species. Its closest relatives live in West Africa.
“It was a big surprise,” Dr. Giribet said.
Dr. Boyer then began investigating the geological history of Florida and found recent research to explain the mystery. Florida started out welded to West Africa near Senegal. North America then collided into them as Pangea was forming.
About 170 million years ago, North America ripped away from West Africa, taking Florida with it. The African ancestors of Florida’s harvestmen came along for the ride.
Dr. Giribet is now searching for other groups of animals that do an equally good job of recording geological history. By comparing dozens or hundreds of animals, he hopes to find clues about the plate tectonics that a single animal could not show.
“This is the beginning of a quest,” he said.
Like NYC needs more air quality problems...
Survey Shows a High Rate of Asthma at Ground Zero
By ANTHONY DePALMA, The New York Times, August 28, 2007
Rescue and recovery workers at ground zero have developed asthma at a rate that is 12 times what would be expected for adults, according to findings released yesterday by the New York City Department of Health and Mental Hygiene.
Of nearly 26,000 workers surveyed in 2003 and 2004, 926 reported that they developed asthma for the first time after working at ground zero (a rate of 3.6 percent). In a group that size, under normal conditions, no more than 77 new cases of asthma (0.3 percent) would have been expected, according to the report, which is published in the current issue of Environmental Health Perspectives, a science and health journal.
The health department also found that workers who arrived at ground zero on Sept. 11, when the dust cloud and smoke from the fires were thickest and respirator masks were least available, had the highest risk of developing asthma in the aftermath of the disaster.
And the rates of new asthma increased the longer workers remained at ground zero, with the risk of developing the disease increasing roughly 3 percent for every 10 days at the site. The study concluded that protective breathing equipment like respirator masks did have “a moderate protective effect” on workers who wore them.
“It is reasonable to conclude that the early initiation and consistent use of appropriate respiratory protection may have further prevented additional cases of new-onset asthma,” the report stated.
The study was based on telephone interviews with workers who enrolled in the World Trade Center Health Registry, a large effort by the city and the federal Centers for Disease Control and Prevention to study the effect of 9/11 on health.
“This corroborates with other studies to say that the risk of respiratory symptoms in workers was elevated after 9/11,” said Lorna Thorpe, the city health department’s deputy commissioner for the division of epidemiology, and a writer of the study. Ms. Thorpe said the study underscored the importance of every ground zero worker or volunteer enrolling in a monitoring program or seeking expert medical care.
The availability of proper respiratory equipment after the twin towers collapsed has been a point of contention between the city and rescue workers, especially firefighters. The standard protective equipment issued to firefighters — masks with small tanks of compressed air — lasted less than a half-hour and then had to be put aside. Some firefighters reported stopping at hardware stores on the way to ground zero to pick up utility dust masks.
After the first several days, respiratory gear became more readily available to firefighters and other workers, but city records indicate that compliance with rules for respirator use was spotty through the entire nine months of the cleanup.
Just wearing some kind of mask did not guarantee safety. The study showed that asthma rates increased even among workers who reported wearing masks. Surgical masks and paper utility masks commonly sold in hardware stores did little to keep out the toxic dust. More sophisticated masks with replaceable cartridges were effective, but only if used properly.
Still, Dr. Thomas R. Frieden, health commissioner, said in a statement that the study underscored the need for protective equipment to be readily available in a disaster response.
“These findings reflect the critical importance of getting appropriate respiratory protection to all workers as quickly as possible during a disaster, and making every effort to make sure that workers wear them at all times,” Dr. Frieden said.
In all, 71,000 people are taking part in the World Trade Center Health Registry. The study released yesterday covered only rescue and recovery workers and did not include office workers, students or downtown residents.
The study has some limitations. Workers who developed asthma may have been more likely to enroll in the registry, or may have reported that the disease began after 9/11 if they were unsure about an earlier diagnosis.
The registry did not attempt to verify diagnoses by comparing responses with existing medical records.
Still, the study is one of the largest and most comprehensive reports linking ground zero dust to respiratory disease.
Later this month, the health department is scheduled to release a report on the mental health effects of ground zero based on the registry data.
The department is also conducting follow-up interviews with people enrolled in the registry. About 60 percent of the 71,000 people on the list have already been contacted.
Really? The Claim: Swallowed Gum Takes a Long Time to Digest
By ANAHAD O’CONNOR, The New York Times, August 28, 2007
THE FACTS
For generations, parents have told their children never to swallow chewing gum, lest it sit undigested for days, weeks or even years.
This is, for the most part, an old wives’ tale. Swallowed chewing gum typically passes through the digestive tract without harm and is eliminated at the same rate as other foods.
But rare complications can occur. The medical literature contains several case reports of people, mostly small children, who developed intestinal obstructions because they had a habit of swallowing their gum. A 1998 study in the journal Pediatrics, for example, described three children who came to a clinic with intestinal pain, constipation and other symptoms, and were found to have small masses of chewing gum in their guts. One was a 4-year-old boy who “always swallowed his gum after chewing five to seven pieces each day.” Another was a 4-year-old girl.
Three other studies, including one in The American Journal of Diseases of Children, describe similar cases. In most, the young patients were fine after removal of the obstructions. The phenomenon is rare, the studies noted. But they might also serve as a cautionary tale for the parents of small children, particularly those with a strong fondness for gum.
THE BOTTOM LINE
Chewing gum is typically digested without harm, though rare complications can occur.
All I could think when I saw this story was that those doctors are not wearing nearly enough protection while handling bats who could potentially have Marburg. This is a disease where "not as bad as ____" doesn't really apply, because not being as bad as Ebola is small consolation. It is pretty big news to have confirmation of the animal reservoir, however.
At a mine in Uganda, left and center, bats are being captured and tested by doctors from the Centers for Disease Control and Prevention, right. International health groups are jointly studying whether the bats harbor the Marburg virus.
Venturing Into the Mines of Uganda, in Search of the Marburg Virus
By NICHOLAS BAKALAR, The New York Times, August 28, 2007
Researchers reported for the first time last week that they have found the Marburg virus in a nonprimate species — bats.
Now, they have turned their attention to a bat-infested lead and gold mine in western Uganda, in an attempt to determine if bats harbor the disease between periodic outbreaks in southern Africa. One miner working in the mine died of Marburg disease on July 14, and several others apparently recovered from it. “We’re trying to see where this goes,” Jonathan Towner, the lead author of the report, published Aug. 22 in the online journal PloS ONE, said in a telephone interview. “We need a good, solid survey of what’s living here and what might have Marburg in it.”
Dr. Towner, a microbiologist with the Centers for Disease Control and Prevention, is working in Ibanda, Uganda, with a group jointly sponsored by the agency, the World Health Organization and the National Institute of Communicable Diseases, a South African government group.
Because Ebola, a closely related virus, had earlier been found in bats, scientists suspected they might harbor Marburg as well. The scientists tested more than 1,100 bats of 10 species in Gabon and Congo and found the virus in four bats of the cave-dwelling species, Rousettus aegyptiacus. The bats, which range all over sub-Saharan Africa, had been trapped in 2005 and 2006 at two locations in Gabon. All of the infected animals appeared healthy.
Marburg infection in humans can be fatal. Symptoms include persistent diarrhea, high fever, bleeding from the nose, gums and vagina, and bloody vomit and feces. There have been periodic occurrences of Marburg in southern Africa during the past three decades, but no one has been able to figure out its natural reservoir — that is, where the virus hides between outbreaks.
If the researchers can confirm that the bat is the reservoir of the virus, the next question is what to do about it. “The knee-jerk reaction is to exterminate all of the bats in the mine,” Dr. Towner said. “But ecologically, that’s a bad thing to do because bats pollinate plants and eat harmful insects by the ton.”
Teaching people how to protect themselves, he continued, may be a better approach. “Wear gloves, hats, masks, and respirators and be mindful of what you stick your hands in,” he said. “And leave the bats alone.”
And while I'm scaring you...
Mite harvestmen, relatives of daddy longlegs, have a typical range of less than 50 miles, and they cannot disperse well.
A Daddy Longlegs Tells the Story of the Continents’ Big Shifts
By CARL ZIMMER, The New York Times, August 28, 2007
Few people have heard of the mite harvestman, and fewer still would recognize it at close range. The animal is a relative of the far more familiar daddy longlegs. But its legs are stubby rather than long, and its body is only as big as a sesame seed.
To find mite harvestmen, scientists go to dark, humid forests and sift through the leaf litter. The animals respond by turning motionless, making them impossible for even a trained eye to pick out. “They look like grains of dirt,” said Gonzalo Giribet, an invertebrate biologist at Harvard.
As frustrating as mite harvestmen may be, Dr. Giribet and his colleagues have spent six years searching for them on five continents. The animals have an extraordinary story to tell: they carry a record of hundreds of millions of years of geological history, chronicling the journeys that continents have made around the Earth.
The Earth’s land masses have slowly collided and broken apart again several times, carrying animals and plants with them. These species have provided clues to the continents’ paths.
The notion of continent drift originally came from such clues. In 1911, the German scientist Alfred Wegner was struck by the fact that fossils of similar animals and plants could be found on either side of the Atlantic. The ocean was too far for the species to have traveled themselves. Wegner speculated — correctly, as it turned out — that the surrounding continents had originally been welded together in a single landmass, which he called Pangea.
Continental drift, or plate tectonics as it is scientifically known, helped move species around the world. Armadillos and their relatives are found in South America and Africa today because their ancestors evolved when the continents were joined. When South America and North America connected a few million years ago, armadillos spread north, too.
Biogeographers can learn clues about this history by comparing related species. To do so, they must also recognize cases where species crossed great stretches of water.
The island of Hawaii, for example, was home to a giant flightless goose that has become extinct. Studies on DNA extracted from its bones show that it evolved from the Canada goose.
Based on its DNA, scientists estimated that the giant goose branched off from Canada geese half a million years ago. That is also when geologists estimate that Hawaii emerged from the Pacific.
When species jump around the planet, their histories blur. It is difficult to say much about where cockroaches evolved, for example, because they can move quickly from continent to continent. This process, known as dispersal, limits many studies.
“Most of them tend to concentrate on particular parts of the world,” Dr. Giribet said. “I wanted to find a new system for studying biogeography at a global scale.”
Dr. Giribet realized that mite harvestman might be that system. The 5,000 or so mite harvestmen species can be found on every continent except Antarctica. Unlike animals found around the world like cockroaches, mite harvestmen cannot disperse well. The typical harvestman species has a range of less than 50 miles. Harvestman are not found on young islands like Hawaii.
“It’s really hard to find a group of species that is distributed all over the world but that also don’t disperse very far,” said Sarah Boyer, a former student of Dr. Giribet, now an assistant professor at Macalester College in St. Paul.
What mite harvestmen lack in mobility, they make up in age. Their ancestors were among the first land animals, and daddy longlegs fossils have been found in 400 million-year-old rocks. Mite harvestmen evolved long before Pangea broke up and have been carried along by continental drift ever since.
“They’ve managed to get themselves around the world only because they’ve been around for hundreds of millions of years,” Dr. Boyer said.
Dr. Boyer, Dr. Giribet and their colleagues set off around the world to collect a diverse group of mite harvestmen. They ended up gathering thousands of animals from which they extracted DNA.
The gene variations helped the scientists build an evolutionary tree. By calculating how quickly the DNA mutated, the scientists could estimate when lineages branched off. They then compared the harvestmen evolution to the movements of the continents.
“The patterns are remarkably clear,” Dr. Boyer said.
She, Dr. Giribet and colleagues are publishing their results papers to appear in The Journal of Biogeography, Cladistics and other journals.
The scientists found that they could trace mite harvestmen from their ancestors on Pangea. One lineage includes species in Chile, South Africa, Sri Lanka and other places separated by thousands of miles of ocean. But 150 million years ago, all those sites were in the same region of southern Pangea, Gondwana.
The harvestmen preserve smaller patterns of continental drift, as well as bigger ones. After analyzing the DNA of a Florida harvestman, Metasiro americanus, the scientists found that it was not related to other North American species. Its closest relatives live in West Africa.
“It was a big surprise,” Dr. Giribet said.
Dr. Boyer then began investigating the geological history of Florida and found recent research to explain the mystery. Florida started out welded to West Africa near Senegal. North America then collided into them as Pangea was forming.
About 170 million years ago, North America ripped away from West Africa, taking Florida with it. The African ancestors of Florida’s harvestmen came along for the ride.
Dr. Giribet is now searching for other groups of animals that do an equally good job of recording geological history. By comparing dozens or hundreds of animals, he hopes to find clues about the plate tectonics that a single animal could not show.
“This is the beginning of a quest,” he said.
Like NYC needs more air quality problems...
Survey Shows a High Rate of Asthma at Ground Zero
By ANTHONY DePALMA, The New York Times, August 28, 2007
Rescue and recovery workers at ground zero have developed asthma at a rate that is 12 times what would be expected for adults, according to findings released yesterday by the New York City Department of Health and Mental Hygiene.
Of nearly 26,000 workers surveyed in 2003 and 2004, 926 reported that they developed asthma for the first time after working at ground zero (a rate of 3.6 percent). In a group that size, under normal conditions, no more than 77 new cases of asthma (0.3 percent) would have been expected, according to the report, which is published in the current issue of Environmental Health Perspectives, a science and health journal.
The health department also found that workers who arrived at ground zero on Sept. 11, when the dust cloud and smoke from the fires were thickest and respirator masks were least available, had the highest risk of developing asthma in the aftermath of the disaster.
And the rates of new asthma increased the longer workers remained at ground zero, with the risk of developing the disease increasing roughly 3 percent for every 10 days at the site. The study concluded that protective breathing equipment like respirator masks did have “a moderate protective effect” on workers who wore them.
“It is reasonable to conclude that the early initiation and consistent use of appropriate respiratory protection may have further prevented additional cases of new-onset asthma,” the report stated.
The study was based on telephone interviews with workers who enrolled in the World Trade Center Health Registry, a large effort by the city and the federal Centers for Disease Control and Prevention to study the effect of 9/11 on health.
“This corroborates with other studies to say that the risk of respiratory symptoms in workers was elevated after 9/11,” said Lorna Thorpe, the city health department’s deputy commissioner for the division of epidemiology, and a writer of the study. Ms. Thorpe said the study underscored the importance of every ground zero worker or volunteer enrolling in a monitoring program or seeking expert medical care.
The availability of proper respiratory equipment after the twin towers collapsed has been a point of contention between the city and rescue workers, especially firefighters. The standard protective equipment issued to firefighters — masks with small tanks of compressed air — lasted less than a half-hour and then had to be put aside. Some firefighters reported stopping at hardware stores on the way to ground zero to pick up utility dust masks.
After the first several days, respiratory gear became more readily available to firefighters and other workers, but city records indicate that compliance with rules for respirator use was spotty through the entire nine months of the cleanup.
Just wearing some kind of mask did not guarantee safety. The study showed that asthma rates increased even among workers who reported wearing masks. Surgical masks and paper utility masks commonly sold in hardware stores did little to keep out the toxic dust. More sophisticated masks with replaceable cartridges were effective, but only if used properly.
Still, Dr. Thomas R. Frieden, health commissioner, said in a statement that the study underscored the need for protective equipment to be readily available in a disaster response.
“These findings reflect the critical importance of getting appropriate respiratory protection to all workers as quickly as possible during a disaster, and making every effort to make sure that workers wear them at all times,” Dr. Frieden said.
In all, 71,000 people are taking part in the World Trade Center Health Registry. The study released yesterday covered only rescue and recovery workers and did not include office workers, students or downtown residents.
The study has some limitations. Workers who developed asthma may have been more likely to enroll in the registry, or may have reported that the disease began after 9/11 if they were unsure about an earlier diagnosis.
The registry did not attempt to verify diagnoses by comparing responses with existing medical records.
Still, the study is one of the largest and most comprehensive reports linking ground zero dust to respiratory disease.
Later this month, the health department is scheduled to release a report on the mental health effects of ground zero based on the registry data.
The department is also conducting follow-up interviews with people enrolled in the registry. About 60 percent of the 71,000 people on the list have already been contacted.
![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png){kind=small}
no subject
Date: 2007-08-28 05:50 pm (UTC)