Stories tagged Cells

Mar
11
2008

Our precious water supply may be at risk
Our precious water supply may be at riskCourtesy Tsjal
Well, this is not good to hear.

An investigation by the Associated Press has revealed that the drinking water of more than two dozen US cities is polluted with pharmaceuticals and over-the-counter drugs.

The medications, which include antibiotics, sex hormones, and mood stabilizers, along with commonly used medications such as ibuprofen, were detected in trace amounts – quantities of parts per billions or even trillions - but let’s face it, this is really disturbing news.

How the drugs got there is obvious; our country’s population is a highly medicated one. We pop a lot pill for all sorts of conditions, headaches, depression, high cholesterol and elevated blood pressure, birth control, sexual dysfunction, to name just a few. Our bodies metabolize a large portion of these drugs but any part not absorbed, ends up going down the toilet and back into the water system.

“People think that if they take a medication, their body absorbs it and it disappears, but of course that’s not the case,” said Christian Daughton, an EPA scientist who was one of the first to bring attention to the issue.

Waste treatment plants filter the water before it gets discharged back into reservoirs or into the water table, and the water is treated again for drinking but unfortunately the treatment plants just aren’t set up to filter out the drug traces. The AP’s five-month investigation also turned up disturbing data that shows some natural watersheds are also contaminated, meaning this stuff is getting into everything.

The trace amounts don’t seem to be a concern, at least not in the short term. But what about in the long term? The effect of ingesting low-levels of all these different types of medications over a lifetime –or even during the critical nine months of gestation – just isn’t clearly understood. Some recent studies have shown disturbing alterations in human cells and wildlife exposed to water laced with pharmaceuticals and industrial pollutants, but these studies aren’t well known to the general population.

And human waste isn’t the only source of contamination. Steroids given to cattle have been shown to find their way from feedlots back into the water system. And here’s an unsettling statistic I learned recently: 75 percent of the antibiotics sold by the US drug companies is used on livestock -such as chickens- to keep them healthy while they grow fat for the slaughterhouse. Some of their manure is then used to fertilize crop fields and the antibiotics get into the aquifers.

So what to do? At the moment, the federal government has no requirement for testing water for drugs and many major cities don’t do it. Less than 50 percent of the 62 cities the AP investigated didn’t test for that kind of contamination. These included major metropolitan centers such as Baltimore, Boston, Chicago, Houston, Chicago, New York City and Phoenix. Some water providers told the AP investigators that they had found no traces of pharmaceuticals in their water, only to have an independent test show that wasn’t true.

You might think, as I did, that maybe bottled water is the answer. Unfortunately much of that is just repackaged (and untested) tap water. And most home purification systems don’t filter out drug contaminates. There is a process called reverse osmosis that can rid the water of all traces of medical contaminants but at the moment, it is very expensive and results in a lot of contaminated waste water just to get a single gallon of potable water.

And the US is not alone in this problem. Traces of pharmaceuticals have been detected in lakes, rivers, reservoirs, and aquifers around the world. Considering that only 3 percent of Earth’s water is fresh water, something needs to be done.

SOURCE and LINKS
AP Story

Mar
04
2008

National Sleep Awareness Week® (NSAW), is a public education, information, and awareness campaign that coincides with the return of Daylight Saving Time, the annual "springing forward" of clocks that can cause Americans to lose an hour of sleep.
--NSAW website (NSAW.org)

Check out the sleep quizzes, tools and other information on the National Sleep Foundation website.

  • Do you get enough sleep?
  • What are you planning to do to recognize NSAW?
  • Share your sleep strategies with us!
Feb
20
2008

Researchers at Yale School of Medicine developed a blood test with enough sensitivity and specificity to detect early stage ovarian cancer with 99 percent accuracy.

Why is this important?
Ovarian cancer is (from the United States Cancer Statistics):

  • the fifth leading cause of cancer-related death in women in the United States
  • the leading cause of gynecologic cancer deaths
  • one-tenth as common as breast cancer but three times more lethal
  • carries a 1:70 lifetime risk

The high rate of death due to ovarian cancer is a result of the lack of a good screening strategy to detect early stage disease. There is currently no proven screening test for ovarian cancer – no mammogram or Pap smear equivalent. It is this reason that women must become extremely diligent about understanding symptoms and talking with their doctors. Additionally, this makes ovarian cancer difficult to diagnose. The Minnesota Ovarian Cancer Alliance and the Centers for Disease Control have more information about ovarian cancer.

What’s the test?
The researches looked at six different proteins in the blood of 362 healthy controls and 156 newly diagnosed ovarian cancer patients. Four of the proteins are related to the normal physiology of the ovaries and the levels of these proteins are maintained by a delicate balance in the body. They hypothesize that the abnormal or cancer cells alter this delicate balance producing the atypical amounts in the blood. They are not necessarily factors that are produced by the tumor (like the additional two proteins) but represent the body’s response to the cancer. The researchers go on to propose that significant levels of the tumor's products (the additional two proteins studied) could only be detected in the blood at later stages of tumor development. Therefore based on this study the protein panel identified can detect early stages of the disease.

Conclusion
This study was a phase II study – meaning more testing is needed. This test is better then the only currently available test, CA-125. The use of this test will enhance the potential of treating ovarian cancer in its early stages and therefore, increases the successful treatment of the disease (Vistintin et. al. Clin Cancer Res 2008:14(4) February 15, 2008). But it still isn’t good enough to use as screening test for the general population. The researchers for this study have begun a phase III evaluation in a multi-center clinical trial. In collaboration with EDRN/NCI and Laboratories Corporation of America (LabCorp), they are testing close to 2,000 patients (Yale news release).

Feb
05
2008

Hetero, homo, and 3-way embryo creation

Embryo - 5 weeks
Embryo - 5 weeksCourtesy Ed Uthman
Lesbian couples could one day have children who share both their genes. Karim Nayernia, Professor of Stem Cell Biology at Newcastle University, has applied for ethical approval from the university to use bone marrow stem cells from women to start experiments to derive female sperm.

“I think, in principle, it will be scientifically possible,” Prof Nayernia told New Scientist.

Babies from two men

Other research is setting the stage for a gay man to donate skin cells that could be used to make eggs, which could then be fertilized by his partner’s sperm. A surrogate's uterus would be needed to bring the baby to term.

In Brazil, a team led by Dr Irina Kerkis of the Butantan Institute in Saõ Paulo claims to have made both sperm and eggs from cultures of male mouse embryonic stem cells in the journal Cloning and Stem Cells.

Babies from a man and two women

A whole class of hereditary diseases, including some forms of epilepsy, result from faulty DNA related to mitochondria. Starting with 10 severely abnormal embryos left over from traditional fertility treatment, researchers removed the nucleus, containing DNA from the mother and father, from the embryo, and implanted it into a donor egg whose DNA had been largely removed. The only genetic information remaining from the donor egg was the tiny bit that controls production of mitochondria. The embryos then began to develop normally, but were destroyed within six days.

"We believe that from this work, and work we have done on other animals that in principle we could develop this technique and offer treatment in the forseeable future that will give families some hope of avoiding passing these diseases to their children." said Patrick Chinnery, a member of the Newcastle team.

If you have an opinion on these types of research, feel free to comment.

Read more

Jan
29
2008

Often you read about people afraid or worried about vaccines but a recent article published in the Journal of the American Medical Association reports that vaccines have decreased hospitalizations and deaths related to the most vaccine-preventable diseases. And occurrences of these diseases are at an all time low. The researchers compared illness and death before and after widespread implementation of national vaccine recommendations for 13 different vaccine-preventable diseases. These include: diphtheria, invasive Haemophilus influenzae type b, hepatitis A, acute hepatitis B, measles, mumps, pertussis, poliomyelitis, rubella, Streptococcus pneumoniae, smallpox, tetanus and varicella. The data showed large reductions in the number of cases after vaccinations were recommended for each of the diseases. For an interesting view of a vaccine life cycle go to this web site

Vaccines changed medicine
(From the Vaccine Education Center)
Official Rubella Fighter: The “rubella umbrella” campaign urged parents to have their children immunized from this viral infection. Rubella, or more commonly referred to as the German measles, is a mild childhood illness that can pose a serious threat to a fetus, if the mother contracts the illness during pregnancy. More than 20,000 babies were born with congenital rubella syndrome (CRS) during an outbreak of rubella in 1964-65. This epidemic cost the country an estimated $1.5 billion. The rubella vaccine was first licensed in the U.S. in 1969.
Official Rubella Fighter: The “rubella umbrella” campaign urged parents to have their children immunized from this viral infection. Rubella, or more commonly referred to as the German measles, is a mild childhood illness that can pose a serious threat to a fetus, if the mother contracts the illness during pregnancy. More than 20,000 babies were born with congenital rubella syndrome (CRS) during an outbreak of rubella in 1964-65. This epidemic cost the country an estimated $1.5 billion. The rubella vaccine was first licensed in the U.S. in 1969.Courtesy CDC

Vaccines have literally transformed the landscape of medicine over the course of the 20th century.

Before vaccines, parents in the United States could expect that every year:
• Polio would paralyze 10,000 children.
• Rubella (German measles) would cause birth defects and mental retardation in as many as 20,000 newborns.
• Measles would infect about 4 million children, killing 3,000.
• Diphtheria would be one of the most common causes of death in school-aged children.
• A bacterium called Haemophilus influenzae type b (Hib) would cause meningitis in 15,000 children, leaving many with permanent brain damage.
• Pertussis (whooping cough) would kill thousands of infants.
Vaccines have reduced and, in some cases, eliminated many diseases that killed or severely disabled people just a few generations before. For most Americans today, vaccines are a routine part of healthcare.

However, the disappearance of many childhood diseases has led some parents to question whether vaccines are still necessary. Further, a growing number of parents are concerned that vaccines may actually be the cause of diseases such as autism, hyperactivity, developmental delay, attention deficit disorder, diabetes, multiple sclerosis, and sudden infant death syndrome (SIDS) among others. These concerns have caused some parents to delay vaccines or withhold them altogether from their children.
For information on vaccine safety go to this page on the CDC website or this page on the Vaccine Education Center website.

How vaccines work
(from the CDC)

Children are born with a full immune system composed of cells, glands, organs, and fluids that are located throughout his or her body to fight invading bacteria and viruses. The immune system recognizes germs that enter the body as "foreign" invaders, or antigens, and produces protein substances called antibodies to fight them. A normal, healthy immune system has the ability to produce millions of these antibodies to defend against thousands of attacks every day, doing it so naturally that people are not even aware they are being attacked and defended so often (Whitney, 1990). Many antibodies disappear once they have destroyed the invading antigens, but the cells involved in antibody production remain and become "memory cells." Memory cells remember the original antigen and then defend against it when the antigen attempts to re-infect a person, even after many decades. This protection is called immunity.
Vaccines contain the same antigens or parts of antigens that cause diseases, but the antigens in vaccines are either killed or greatly weakened. When they are injected into fatty tissue or muscle, vaccine antigens are not strong enough to produce the symptoms and signs of the disease but are strong enough for the immune system to produce antibodies against them (Tortora and Anagnostakos, 1981). The memory cells that remain prevent re-infection when they encounter that disease in the future. Thus, through vaccination, children develop immunity without suffering from the actual diseases that vaccines prevent. But remember…what's in the vaccine is just strong enough to promote the body's response to make antibodies, but much weaker than the viruses or bacteria in their natural, or "wild," states. For another description see this webpage

Jan
26
2008

Template for life created out of lab chemicals

Mycoplasma genitalium
Mycoplasma genitaliumCourtesy Department of Energy
Starting with simple laboratory chemicals, a group of scientists led by Craig Venter have replicated an entire bacterial genome. Based on an existing organism, the molecule of DNA Mycoplasma genitalium, composed of 582,970 base pairs, could come "alive" and start to replicate itself when inserted into a "hollow" bacterial host from which the DNA has been removed. The procedure titled, Complete Chemical Synthesis, Assembly, and Cloning of a Mycoplasma genitalium Genome was just published in Science.

"Venter and his colleagues have already managed to transplant the DNA from one bacteria into another, making it change species (see Genome transplant makes species switch/news070625-9). These bacteria were closely related to M. genitalium. If the transplant can be repeated with a man-made genome adapted from M. genitalium, the result could qualify as the first artificial life form (see 'What is artificial life?')" Nature News.

Customizing bacteria to solve problems

The genome of M. genitalium is one of the simplest, consisting of only 470 coding regions. Venter suspects about 100 of these are not necessary. The next step is to strip out various segments in an attempt to build the minimal amount of code that is essential for "life". This minimal component could then serve as a chassis to which "designer" genes could be attached, genes that could turn the bacteria into biological factories for making hydrogen (or other fuels).

Recommended reading:
Longest Piece of Synthetic DNA Yet (Scientific American)

Jan
22
2008

Human embryos using animal eggs

Embryo, 8 cells
Embryo, 8 cellsCourtesy Ekem
Last week we learned that scientists cloned human embryos using adult skin and fertile eggs from a woman donor. Now the Human Fertilization and Embryology Authority in Britain has approved creating human embryos using eggs from animals like cows or rabbits. Because the animal cell's nucleus would be removed before human DNA was added, scientists said the resulting egg would not be a chimera.

"Cow eggs seem to be every bit as good at doing this job as human eggs," said Lyle Armstrong of Newcastle University.
"We will only use them as a scientific tool and we need not worry about cells being derived from them ever being used to treat human diseases," Armstrong said.

Technique eliminates destruction of human eggs

Animal eggs are abundant and easily obtained. Researchers hope to refine their techniques by practicing first on animal eggs to producing human stem cells. Human stem cells, which have the ability to develop into any cell in the human body, show promise for understanding and healing many human ailments. The embryos would not be allowed to develop for more than two weeks.

Jan
22
2008

Decellularization: A rat heart as the cells are removed (left three images) and replaced (right two images) over time.
Decellularization: A rat heart as the cells are removed (left three images) and replaced (right two images) over time.Courtesy Thomas Matthiesen, University of Minnesota

Science fiction?
Did you know that nearly 5 million people live with heart failure? More surprisingly, approximately 50,000 United States patients die annually waiting for a donor heart.

University of Minnesota researchers recently announced they have created a beating heart in the laboratory. It sounds like science fiction, but it is a real medical breakthrough. The researchers removed the tissue from a dead rat heart and replaced it with living cells from newborn rats. With the help of electrical signals, the entire heart began to beat.

"Ghost hearts"
The researchers used a detergent to remove the cells from the rat hearts. This left behind only the nonliving fibers that give the heart its shape. The result was a white, rubbery, 3-D “skeleton”. This structure, called the extracellular matrix, allows cells to attach and grow into tissue, and gives the heart muscle something to pull against. The researchers injected cells from newborn rats into the left ventricle and pumped oxygen and nutrients through the structure of blood vessels. They helped the process by sending electrical signals through the new tissue. In eight days, the hearts were pumping – some continued beating for 40 days.

The supply of donor organs is limited and the risks for infection or rejection of the transplanted organ can be high. If the technique is perfected, doctors may be able to use patients’ own stem cells to recellularize a donor heart.

The next steps
The University of Minnesota research team has successfully decellularized pig hearts, and hopes that other types of organs can be created in the future.

Jan
18
2008

Blastocyst day 5
Blastocyst day 5Courtesy Ekem

DNA from clone identical to that from adult skin donor

A paper published in the online journal, Stem Cells, yesterday titled "Development of Human cloned Blastocysts Following Somatic Cell Nuclear Transfer (SCNT) with Adult Fibroblasts" is the first documented demonstration that ordinary cells from an adult human can be used to make cloned embryos mature enough to produce stem cells

"A research team at Stemagen, a biotech company based in San Diego, California, started with skin cells donated by two men and 25 eggs, or oocytes, donated by women at a nearby fertility center. The scientists removed the DNA-containing nuclei from the eggs and replaced them with DNA from the donor skin cells. Two of the eggs became 5-day-old embryos, or blastocysts, that were clones of the male donors."Science

Why are we cloning humans?

The next big step will be to create a human embryonic stem cell line from cloned embryos. Stem cells from cloned embryos could provide a valuable tool for studying diseases, screening drugs, and creating transplant material to treat conditions like diabetes and Parkinson's disease.

Should we be doing this?

As expected, critics are raising objections. This procedure requires cutting healthy eggs out of women, then altering them to produce living embryos, which are then destroyed. Should this be allowed?

Read more

Jan
14
2008

Dead heart transformed into a living heart

Tissue engineering has allowed a dead rat heart to be stripped of its cellular material, then after injecting the remaining scaffold material with with new cardiac cells, the cells organized themselves until the heart became alive.

A "crazy idea" at the University of Minnesota that could not get federal funding yielded "unbelievable" results after getting funding from the University of Minnesota and from the Medtronic Research Foundation.

New source for replacement organs

The accomplishment gave a significant boost to medicine’s dream of growing human organs to replace damaged ones. Organ transplants usually require replacement organs that fulfill extreme compatibility issues. By using the patients own cells in the rebuilt organs scientists hope to eliminate the need for patients to take anti-rejection drugs for the rest of their lives.

Growing human hearts at least 10 years away, if ever

The next step will be to use these techniques on pig hearts. Pig hearts are similar enough to a humans that parts from them have already been used in humans.

"Although this is only a first step requiring considerable follow-up development, the study nevertheless represents an exciting breakthrough that will eventually make the prospect of repairing damaged hearts a reality and will also be an approach that can be extended to other organs." Dr Jon Frampton Wellcome Trust Senior Fellow at the University of Birmingham

Source articles
TwinCities.com
New York Times
BBC News
USA Today
Nature Medicine journal's Perfusion-decellularized matrix: using nature's platform to engineer a bioartificial heart (abstract)