This is a REALLY interesting website from the Howard Hughes Medical Institute (HHMI) about how to verify a persons gender. Click on the link and scroll down to 'Gender Testing for Female Athletes.... find out why'.
Read the information then 'begin exploring'.
Be sure to read about male development and CAIS.
http://www.hhmi.org/biointeractive/gender/index.html
What do you think? Share your comments with the class.
Friday, September 18, 2009
Wednesday, September 16, 2009
Male bass in many US rivers feminized, study finds
By SETH BORENSTEIN, AP Science Writer
– Mon Sep 14, 5:54 pm ET
WASHINGTON – Government scientists figure that one out of five male black bass in American river basins have egg cells growing inside their sexual organs, a sign of how widespread fish feminizing has become.
The findings come from the U.S. Geological Survey in its first comprehensive examination of intersex fish in America, a problem linked to women's birth control pills and other hormone treatments that seep into rivers. Sporadic reports of feminized fish have been reported for a few years.
The agency looked at past data from nine river basins — covering about two-thirds of the country — and found that about 6 percent of the nearly 1,500 male fish had a bit of female in them. The study looked at 16 different species, with most not affected.
But the fish most feminized are two of the most sought-after freshwater sportfish: the largemouth and smallmouth, which are part of the black bass family. Those two species were also the most examined with nearly 500 black bass tallied.
"It's widespread," said USGS biologist Jo Ellen Hinck. She is the lead author of the study, published online this month in Aquatic Toxicology. She said 44 percent of the sites where black bass were tested had at least one male with egg cells growing inside.
Past studies have linked the problem to endocrine-disrupting hormones, such as estrogen from women's medicines. While the fish can still reproduce, studies have shown they don't reproduce as well, Hinck said.
Intersex fish are also seen as a general warning about what some experts see as a wider problem of endocrine disruptors in the environment.
The egg cells growing in the male fish's gonads can only be seen with a microscope after the fish has been caught and dissected.
The study used data from 1995 to 2004, when the government stopped funding the research. The only river basin examined that didn't show any problems was Alaska's Yukon River Basin.
The Southeast, especially the Pee Dee River Basin in North and South Carolina, had the highest rates of feminization. In Bucksport, S.C., 10 of 11 largemouth bass examined were intersex. In parts of the Mississippi River in Minnesota and the Yampa River in Colorado, 70 percent of the smallmouth bass had female signs.
Hinck said black bass seem to be more prone to the problem, but researchers don't know why. She also found one common carp that was female with bits of male testes growing inside.
– Mon Sep 14, 5:54 pm ET
WASHINGTON – Government scientists figure that one out of five male black bass in American river basins have egg cells growing inside their sexual organs, a sign of how widespread fish feminizing has become.
The findings come from the U.S. Geological Survey in its first comprehensive examination of intersex fish in America, a problem linked to women's birth control pills and other hormone treatments that seep into rivers. Sporadic reports of feminized fish have been reported for a few years.
The agency looked at past data from nine river basins — covering about two-thirds of the country — and found that about 6 percent of the nearly 1,500 male fish had a bit of female in them. The study looked at 16 different species, with most not affected.
But the fish most feminized are two of the most sought-after freshwater sportfish: the largemouth and smallmouth, which are part of the black bass family. Those two species were also the most examined with nearly 500 black bass tallied.
"It's widespread," said USGS biologist Jo Ellen Hinck. She is the lead author of the study, published online this month in Aquatic Toxicology. She said 44 percent of the sites where black bass were tested had at least one male with egg cells growing inside.
Past studies have linked the problem to endocrine-disrupting hormones, such as estrogen from women's medicines. While the fish can still reproduce, studies have shown they don't reproduce as well, Hinck said.
Intersex fish are also seen as a general warning about what some experts see as a wider problem of endocrine disruptors in the environment.
The egg cells growing in the male fish's gonads can only be seen with a microscope after the fish has been caught and dissected.
The study used data from 1995 to 2004, when the government stopped funding the research. The only river basin examined that didn't show any problems was Alaska's Yukon River Basin.
The Southeast, especially the Pee Dee River Basin in North and South Carolina, had the highest rates of feminization. In Bucksport, S.C., 10 of 11 largemouth bass examined were intersex. In parts of the Mississippi River in Minnesota and the Yampa River in Colorado, 70 percent of the smallmouth bass had female signs.
Hinck said black bass seem to be more prone to the problem, but researchers don't know why. She also found one common carp that was female with bits of male testes growing inside.
Sunday, September 13, 2009
A Spineless Solution
Sep 3rd 2009
From The Economist print edition
A better way to find novel antibiotics
Science Photo Library Wriggle for the camera, please
NEW antibiotics are always welcome. Natural selection means the existing ones are in constant danger that pathogens will evolve resistance to them. But winnowing the few chemicals that have antibiotic effects from the myriad that might do, but don’t, is tedious. So a technique invented recently by Frederick Ausubel of Harvard University and his colleagues, which should help to speed things up, is welcome.
Dr Ausubel’s method, the details of which have just been published in ACS Chemical Biology, employs nematode worms of a species called C. elegans as its sacrificial victims. C. elegans is one of the most intensively studied animals on Earth (it was the first to have its genome read completely). It is a mere millimetre long, and can be mass produced to order, so it is ideal for this sort of work.
Dr Ausubel set out to make an automated system that could infect worms with bacteria, treat them with chemical compounds that might have antibiotic effects, and then record the results. The device he has built starts by laying the worms on a “lawn” of pathogenic bacteria for 15 hours and then mixing them with water to create a sort of worm soup. It then places the infected worms into individual enclosures, using a machine called a particle sorter that is able to drop a precise number of worms (in this case 15) into each of 384 tiny wells arrayed on a single plate. These wells have, in turn, each been pre-loaded with a different chemical that is being tested for possible antibiotic properties. Once in place, the worms are left alone for five days.
Until now, researchers engaging in this sort of work have had to monitor each wellful of worms by eye (assisted by a microscope) to determine whether the inmates were alive or dead. To avoid this time-consuming process, Dr Ausubel and his team exposed their worms to an orange stain once the five days were over. The stain in question enters dead cells easily, but cannot enter living ones. They were thus able to distinguish the quick from the dead by colour, rather than propensity to wriggle.
Moreover, using a stain in this way meant they could automate the process by attaching a camera to the microscope, taking photographs of all 384 wells, and feeding the images into a computer that had been programmed to measure the area of orange in a well and contrast that with the total area occupied by worms. When they compared this automated mechanism for identifying dead worms with manual methods that depended upon human eyes, they found it was every bit as effective.
So far Dr Ausubel and his colleagues have managed to test around 37,000 compounds using their new method, and they have found 28 that have antibiotic properties. Their most exciting discovery is that some of these substances work in completely different ways from existing antibiotics. That means entirely new types of resistance mechanism would have to evolve in order for bacteria to escape their effects.
Mass screening of this sort is not, itself, a new idea in the search for drugs, but extending it so that it can study effects on entire animals rather than just isolated cells should make it even more productive. And worms, unlike, say, white mice, have few sentimental supporters in the outside world.
Friday, September 11, 2009
Liposuction Fat Turned Into Stem Cells, Study Says
John Roach for National Geographic News
September 8, 2009
The research appears online today in the journal Proceedings of the National Academy of Sciences.
Using leftovers from liposuction patients, scientists have turned human fat into stem cells, a new study says.
The discovery may also help avoid the controversy spawned by the use of stem cells from human embryos.
Human fat is "an abundant natural resource and a renewable one," said Stanford University plastic surgeon Michael Longaker, whose liposuction patients donated the fat for the study.
Longaker envisions a future in which doctors will be able to use fat from a patient to grow, in a lab, new tissues and organs for that patient.
The opportunity wouldn't be limited to the obese.
"Even if you're in great shape, there is still enough fat to be harvested from the vast majority of patients," added Longaker, who co-authored the study.
From Fat to Stem Cells to New Organs?
The reprogrammed cells, called induced pluripotent stem cells, or iPS cells, are capable of turning into most types of cells in the body.
Scientists are keen to obtain these cells to study disease and, one day, use them to grow new tissue and replacement organs.
Previously, researchers had shown that they could derive this type of stem cell from ordinary skin cells.
But the fat technique is about twice as fast and 20 times more efficient, said Joseph Wu, the study's senior author.
"We can get iPS-like colonies, basically, in about 16 days, compared to 28 days to 32 days using [skin]," said Wu, a Stanford stem cell expert. "And if you count the number of colonies in [skin] versus fat ... we get about 20 times more the number of iPS colonies."
Reprogramming Cells
To create the stem cells, the scientists injected Trojan horse-like viruses into smooth muscle cells found in fat that surrounds blood vessels. Once inside, the viruses introduced genes that reprogrammed the cells, spurring them to grow into new forms.
Previously, this process had required growing the stem cells in a culture dish with nutrients from mouse cells. This had raised alarms about the potential for contamination from mouse proteins—a potential obstacle to government approval, Longaker, the plastic surgeon, said.
That the new method works at all is "somewhat surprising" and remains something of a mystery, Longaker said.
Sidestepping Stem Cell Controversy
The fat and skin methods allow researchers to sidestep the ethical controversy over the use of embryonic stem cells from cell lines originally harvested from unused human embryos from in vitro fertilization clinics.
In addition, Longaker noted, tissue or organs grown from a patient's own stem cells should be less likely to be rejected by the body.
The speediness of the fat method, in particular, could be lifesaving, he added.
For example, if a surgeon wanted to implant new heart tissue—derived from a heart attack victim's own fat—into a patient, the doctor might have only a short time before scar tissue would compromise the operation.
If he or she were able to generate the tissue within a few weeks, Longaker said, that "would be a big deal."
Wednesday, September 9, 2009
Strange jellies of the icy depths
Matt Walker
September 1, 2009
Editor, Earth News
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8231000/8231367.stm
The small blue jelly, a type of Narcomedusae, is new to science.
One of the biggest surprises is that one of the most common animals in the Arctic deep sea is a type of jellyfish that is completely new to science.
The deep Arctic ocean is isolated from much of the water elsewhere on the globe. One area, known as the Canadian Basin, is particularly cut off by deep-sea ridges. These huge barriers can isolate any species there from other deep-water animals.
So in 2005, an international team of scientists, funded primarily by the US National Oceanic and Atmospheric Administration's Office of Ocean Exploration and Research, conducted a series of deep-sea dives using a remote operated vehicle (ROV).
However, the other common jelly was a species new to science.
"Probably the single most interesting discovery was a new species of a small blue jellyfish, from a group called the Narcomedusae," says Dr Raskoff.
"This group has several interesting features that set them apart from typical jellyfish, such as the fact that they hold their tentacles over their bell as they swim."
Most jellyfish let their tentacles drift in the water behind them, but the new species holds its tentacles out in front, perhaps enabling it to better catch prey.
The new species is so unusual that it has been classified within its own genus, and will be formally described later this year.
"It was also the third most common jellyfish found on the cruise, which is really surprising when you think about the fact that even the most common species in the area can be totally new and unexpected species," says Dr Raskoff.
Another striking find was a type of ctenophore called Aulacoctena, which is one of the most spectacular examples of its kind.
At over 15cm long, its tentacles can grip almost anything underwater, yet little is known about its lifestyle.
However, one of the specimens collected by the ROV ejected its stomach contents, which revealed it may had fed on a bright orange animal.
The researchers suspect it feeds on bright orange worms that also live in the Arctic deep, and it gets it colour from its prey.
The scientists are now keen to find out much more about how these strange and enigmatic creatures interact with their environment, and how they influence or underpin the ecology of the deep ocean in which they live.
They also hope to raise funds to explore other little-visited regions of the deep Arctic ocean, as well as exploring the Aleutian trench off the coast of Alaska.
"You don't have to go too far to find interesting areas to study, you just have to dive deep," says Dr Raskoff.
September 1, 2009
Editor, Earth News
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8231000/8231367.stm
Crossota millsae, a brilliant red and purple jellyfish found at a depth of 2000m in the Arctic Ocean, is also found off California and Hawaii.
New details are emerging about the life-forms that survive in one of the world's most inaccessible places.
Scientists have published descriptions of a range of jelly-like animals that inhabit the deep oceans of the Arctic.
The animals were originally filmed and photographed during a series of submersible dives in 2005.
The small blue jelly, a type of Narcomedusae, is new to science.One of the biggest surprises is that one of the most common animals in the Arctic deep sea is a type of jellyfish that is completely new to science.
The deep Arctic ocean is isolated from much of the water elsewhere on the globe. One area, known as the Canadian Basin, is particularly cut off by deep-sea ridges. These huge barriers can isolate any species there from other deep-water animals.
So in 2005, an international team of scientists, funded primarily by the US National Oceanic and Atmospheric Administration's Office of Ocean Exploration and Research, conducted a series of deep-sea dives using a remote operated vehicle (ROV).
The large bright orange Aulacoctena species may get its colour from worms that it eats
Details of what they found have now been published in the journal Deep Sea Research Part II.
"There were a lot of surprises," says biologist Dr Kevin Raskoff of Monterey Peninsula College in California, US, a leading member of the dive team.
"One thing was just how many different jellies there were, and the sizes of their populations."
"Some were somewhat well known from other oceans, but had not previously been found in the Arctic. That caused us to rethink our ideas about what the typical habitat would be for the species. We also discovered a number of new species that had not been found before."
Chrysaora melanaster is one of the largest Arctic jellies, living in the top layer of water at depths of between 20m and 40m, where the temperature remains nearly constant.
During a series of dives to depths of 3000m, the ROV filmed over 50 different types of gelatinous or jelly-like animal.
The majority of animals recorded were Medusae, a particular type of jellyfish that tend to be bell or disc shaped.
The majority of animals recorded were Medusae, a particular type of jellyfish that tend to be bell or disc shaped.
This red-lipped cydippid ctenophore was a common deep-water species between 1,300 to 2,400m. It still awaits description
Other jelly-like creatures seen included ctenophores, an unusual group that can look like jellyfish, but are not able to sting, siphonophores, which are actually colonies of smaller animals living together in a structure that looks like a single, larger animal, and larvaceans, plankton-like creatures unrelated to jellyfish.
Of all the Medusae observed, two species dominated at most locations visited by the ROV.
The first was a species called Sminthea arctica, which lived at depths ranging from 100m to 2,100m. This jellyfish has been recorded before by scientific expeditions. 
However, the other common jelly was a species new to science.
"Probably the single most interesting discovery was a new species of a small blue jellyfish, from a group called the Narcomedusae," says Dr Raskoff.
"This group has several interesting features that set them apart from typical jellyfish, such as the fact that they hold their tentacles over their bell as they swim."
Most jellyfish let their tentacles drift in the water behind them, but the new species holds its tentacles out in front, perhaps enabling it to better catch prey.
The new species is so unusual that it has been classified within its own genus, and will be formally described later this year.
"It was also the third most common jellyfish found on the cruise, which is really surprising when you think about the fact that even the most common species in the area can be totally new and unexpected species," says Dr Raskoff.
Another striking find was a type of ctenophore called Aulacoctena, which is one of the most spectacular examples of its kind.
At over 15cm long, its tentacles can grip almost anything underwater, yet little is known about its lifestyle.
However, one of the specimens collected by the ROV ejected its stomach contents, which revealed it may had fed on a bright orange animal.
The researchers suspect it feeds on bright orange worms that also live in the Arctic deep, and it gets it colour from its prey.
The scientists are now keen to find out much more about how these strange and enigmatic creatures interact with their environment, and how they influence or underpin the ecology of the deep ocean in which they live.
They also hope to raise funds to explore other little-visited regions of the deep Arctic ocean, as well as exploring the Aleutian trench off the coast of Alaska.
"You don't have to go too far to find interesting areas to study, you just have to dive deep," says Dr Raskoff.
Tuesday, September 1, 2009
Genetic test detects infections before symptoms appear
By Steve Sternberg, USA TODAY
8/6/2009
Flu sufferers of the future may not have to wait until their fever spikes to learn they're ill, scientists said Thursday.
Geoffrey Ginsburg of Duke University and his colleagues say that they've developed an experimental genetic test that can detect infections before any symptoms appear.
Although the test cannot yet distinguish one virus from another, it can tell the difference between a bacterial and a viral illness, Ginsburg says.
Most diagnostic tests detect the germ itself or antibodies produced by the immune system to wipe out a virus or bacteria once the symptoms begin. The new approach works differently, by detecting genetic signs of infection in people who aren't sick yet.
The test betrays the activation of genes that govern an immune response. It is carried out using a silicon chip much like those used in computers and requires no more than the 10 microliters of blood from a finger-prick.
"This is the first major step in using a person's individual response to a viral or bacterial infection to lead to better diagnostics for infectious disease," Ginsburg says.
The goal of the research, sponsored by the U.S. military's Defense Advanced Research Projects Agency (DARPA), is to develop a device that can identify troops who are getting sick, in time to get them treated and to prevent them from infecting others. Ultimately, Ginsberg says, the method could also become a valuable diagnostic tool in emergency rooms and doctors' offices, where a simple test could tell the difference between the worried well and the genuinely sick.
"The true market for this may be in doctors' offices around the world, where kids are coming in with fevers and doctors have to make decisions about giving them an antibiotic," he says, noting that antibiotics can be expensive, have side effects and promote the spread of drug-resistant germs.
Arnold Monto, of the University of Michigan School of Public Health, says a test that could accurately identify viral illness, especially influenza, would be a critically important advance. "A chip like this would be great," Monto says. Not only would it help doctors more accurately diagnose people who are ill, but it would also provide public health officials with information critical to their efforts to fight epidemics.
The accuracy of the rapid tests that are currently available is inconsistent, ranging from 30% to 80%, and prompting public health officials to caution against their use. An accurate genetic test would serve multiple purposes, Monto says.
"If we could identify people before they get sick — say, in household studies — we could get a better idea of how the virus is transmitting," he says. "How influenza is transmitted affects (predictions of an epidemic's spread), control measures and personal protective measures," shedding light on how best to keep from getting infected.
Ginsburg and his team tried out the method in volunteers they infected with cold viruses, flu viruses and a less well-known cause of upper airway disease called respiratory syncytial virus. The study appears today in the journal Cell, Host & Microbe.
The study involved 57 volunteers. Their blood was drawn before and after they were infected so that each one could serve as a healthy control.
Researchers were able to tell the difference someone who was infected and someone who wasn't with 95% accuracy. The test could also distinguish between people who were infected with viruses and those with bacteria more than 93% of the time.
The researchers are trying to determine whether the test will work in patients infected with H1N1, or swine, flu.
8/6/2009
Flu sufferers of the future may not have to wait until their fever spikes to learn they're ill, scientists said Thursday.
Geoffrey Ginsburg of Duke University and his colleagues say that they've developed an experimental genetic test that can detect infections before any symptoms appear.
Although the test cannot yet distinguish one virus from another, it can tell the difference between a bacterial and a viral illness, Ginsburg says.
Most diagnostic tests detect the germ itself or antibodies produced by the immune system to wipe out a virus or bacteria once the symptoms begin. The new approach works differently, by detecting genetic signs of infection in people who aren't sick yet.
The test betrays the activation of genes that govern an immune response. It is carried out using a silicon chip much like those used in computers and requires no more than the 10 microliters of blood from a finger-prick.
"This is the first major step in using a person's individual response to a viral or bacterial infection to lead to better diagnostics for infectious disease," Ginsburg says.
The goal of the research, sponsored by the U.S. military's Defense Advanced Research Projects Agency (DARPA), is to develop a device that can identify troops who are getting sick, in time to get them treated and to prevent them from infecting others. Ultimately, Ginsberg says, the method could also become a valuable diagnostic tool in emergency rooms and doctors' offices, where a simple test could tell the difference between the worried well and the genuinely sick.
"The true market for this may be in doctors' offices around the world, where kids are coming in with fevers and doctors have to make decisions about giving them an antibiotic," he says, noting that antibiotics can be expensive, have side effects and promote the spread of drug-resistant germs.
Arnold Monto, of the University of Michigan School of Public Health, says a test that could accurately identify viral illness, especially influenza, would be a critically important advance. "A chip like this would be great," Monto says. Not only would it help doctors more accurately diagnose people who are ill, but it would also provide public health officials with information critical to their efforts to fight epidemics.
The accuracy of the rapid tests that are currently available is inconsistent, ranging from 30% to 80%, and prompting public health officials to caution against their use. An accurate genetic test would serve multiple purposes, Monto says.
"If we could identify people before they get sick — say, in household studies — we could get a better idea of how the virus is transmitting," he says. "How influenza is transmitted affects (predictions of an epidemic's spread), control measures and personal protective measures," shedding light on how best to keep from getting infected.
Ginsburg and his team tried out the method in volunteers they infected with cold viruses, flu viruses and a less well-known cause of upper airway disease called respiratory syncytial virus. The study appears today in the journal Cell, Host & Microbe.
The study involved 57 volunteers. Their blood was drawn before and after they were infected so that each one could serve as a healthy control.
Researchers were able to tell the difference someone who was infected and someone who wasn't with 95% accuracy. The test could also distinguish between people who were infected with viruses and those with bacteria more than 93% of the time.
The researchers are trying to determine whether the test will work in patients infected with H1N1, or swine, flu.
Monday, August 31, 2009
Scientists may have new tool in bacteria fight
Methicillin-resistant Staphylococcus aureus bacteria is commonly known as MRSA and is a major source of infections in hospitals. (CDC) -By Scott LaFee
Union-Tribune Staff Writer
August 28, 2009
For years, scientists and doctors have watched with frustration as their arsenal of antibiotics has been reduced by the growing and inevitable emergence of drug-resistant bacteria and other microbes.
What they have needed, what modern medicine requires, is a new way to attack and kill infectious, disease-causing pathogens such as tuberculosis and multidrug-resistant staphylococcus.
In a paper published today in the journal Chemistry & Biology, researchers at Burnham Institute for Medical Research in La Jolla, with colleagues at the University of Texas Southwestern Medical Center and the University of Maryland, say they may have found the basis for a new class of antibacterial agents capable of overcoming current multidrug resistance.
“The importance of emerging antibiotic-resistant pathogens cannot be overstated,” said Dr. Victor Nizet, who studies human immunology and infectious disease at the University of California San Diego. “There's no drug currently in clinical medicine in which there isn't at least one resistant strain of pathological microbe.”
Andrei Osterman, an associate professor at Burnham and member of its Infectious and Inflammatory Disease Center, said the new findings were not a silver bullet. “What we've found is a golden target,” he said.
That target is a bacterial enzyme called NadD, or nicotinate mononucleotide adenylyltransferase. If the enzyme is absent or its activity is suppressed, the bacterium dies. Versions of NadD are found in almost all cells, including human.
Using computer modeling, the researchers matched more than a million chemical compounds against the enzyme, eventually identifying a handful that interacted with and inhibited NadD activity. Subsequent experiments using E. coli and anthrax bacteria confirmed the compounds' inhibitory potential. But the compounds do not affect the human version of the NadD enzyme because its molecular structure is different.
“We're a long way yet from having an actual, new class of antibiotics, something that microbial pathogens have not seen before,” Osterman said. “But this is a major step. It is proof of concept. We've proved that this enzyme is a good target and that by suppressing it, you can kill bacteria.”
Osterman said it will require several more years of testing and research before any new, NadD-based antibiotic might emerge. The newly identified compounds must be further refined and improved, tested for toxicity and effectiveness in animal models and, eventually, in humans.
The bulk of that research will likely occur in academic and institutional settings, not within the pharmaceutical industry, which broadly views antibiotic research as less lucrative than other endeavors. Osterman's research was funded by a grant from the National Institute of Allergy and Infectious Diseases.
Development of a new and effective broad-spectrum antibiotic can't come soon enough. Antibiotic resistance has become a major medical issue, with some pathogens having evolved through random mutations and the misuse of antibiotics to become almost invulnerable to the one-time “wonder drugs.”
Indeed, more than half of all Staphylococcus aureus infections in U.S. hospitals, where it is a persistent scourge – are resistant to formerly potent antibiotics such as penicillin, methicillin, tetracycline and erythromycin, according to the Centers for Disease Control and Prevention. In such cases, only the strongest, newest antibiotics, such as vancomycin, work – and some bacterial strains are now resistant to it.
For a variety of reasons, most pharmaceutical research has tended to focus on tweaking existing drugs to keep them effective or relevant, said UCSD's Nizet, who is also on Burnham's scientific advisory board. But that's clearly not enough.
New chemicals with antibiotic properties must be found – new chinks in microbial armor revealed.
“This research is an example of the latter,” Nizet said. “It's one of a handful of approaches that all have to be pursued in combination because things aren't going to get better anytime soon. Bacteria is perfect proof of evolution in action, constantly adapting to selective life-and-death pressures. These pathogens are not going to go away.”
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