http://www.womenco.com/benefits/articles/3388-15-toughest-interview-questions-and-answers?page=1
1. Why do you want to work in this industry?
Don’t just say you like it. Anyone can do that. Focus instead on your history with that particular industry, and if you can, tell a success story.
2. Tell us about yourself.
Instead of giving a chronological work history, focus on your strengths and how they pertain to the role. If possible, illustrate with examples.
3. What do you think of your previous boss?
Remember: if you get the job, the person interviewing you will some day be your previous boss. The last thing they want is to hire someone who they know is going to badmouth them some day. Instead of trashing your former employer, stay positive, and focus on what you learned from him (no matter how awful he really was).
4. Why are you leaving your current role?
Again, stay away from badmouthing your job or employer. Focus on the positive.
5. Where do you see yourself in five years?
There’s really no right answer to this question, but the interviewer wants to know that you’re ambitious, career-oriented, and committed to a future with the company. So instead of sharing your dream for early retirement, or trying to be funny, give them an answer that illustrates your drive and commitment.
6. What’s your greatest weakness?
This question is a great opportunity to put a positive spin on something negative, but you don’t want your answer to be cliché – joking or not. Instead, try to use a real example of a weakness you have learned to overcome.
7-What is your greatest failure, and what did you learn from it?
You don’t want to actually highlight a major regret – especially one that exposes an overall dissatisfaction with your life. Instead, focus on a smaller, but significant, mishap, and how it has made you a better professional.
Thursday, July 30, 2009
Wednesday, July 22, 2009
Chugai Files NDA for a Renal Anemia Agent R744
http://www.chugai-pharm.co.jp/generalPortal/pages/detailTypeTable.jsp?documentId=doc_14612&lang=en
July 22, 2009 (Tokyo) - Chugai Pharmaceutical Co., Ltd. ("Chugai") [Head Office: Chuo-ku, Tokyo; President Osamu Nagayama] announced that the company filed a new drug application (NDA) for R744, a long-acting erythropoiesis-stimulating agent, for the treatment of anemia associated with chronic kidney disease (renal anemia) with the Japanese Ministry of Health, Labour and Welfare (MHLW) today.
Renal anemia is one of the most frequent complications with chronic kidney disease (CKD), with significant impact on patients' quality of life. R744 is a continuous erythropoietin receptor activator which has a different interaction on the receptor level compared to other erythropoiesis stimulating agents. It was launched outside Japan in 2007 under the product name Mircera® as an innovative anti-anemia medication that allows a once-monthly maintenance therapy. With its extended dosing frequency compared to existing therapies, the product is contributing to the advancement of the management of renal anemia overseas.
Chugai conducted clinical trials for R744 in renal anemia patients in Japan. The results of these studies confirmed its efficacy and tolerability in CKD patients with once-every-four-week intravenous or subcutaneous dosing in maintenance therapy, which led to the filing today.
In recent years, there has been a significant increase in CKD patients with underlying diabetes. The increasing prevalence of CKD raises awareness of the importance of earlier treatment of anemia and simplified anemia management in these patients. To support treatment, guidelines have been issued by the Japanese Society for Dialysis Therapy and the Japanese Society of Nephrology in 2008 and 2009, respectively.
The area of renal diseases is one of the strategic focus areas for Chugai. Chugai will continue to focus on obtaining marketing authorization for R744 to make this new treatment option available for anemic patients with CKD and medical professionals in addition to the currently available standard therapy, the recombinant human erythropoietin EpoginR.
About R744R744 is a long-acting erythropoiesis stimulating agent (ESA) which has the longest serum half-life among ESAs on the market. The long serum half-life of R744 allows maintenance of hemoglobin level with once-every-four-week dosing for CKD patients, offering simplified anemia management and improved convenience for patients and caregivers. R744 is marketed outside Japan under the product name Mircera®.
July 22, 2009 (Tokyo) - Chugai Pharmaceutical Co., Ltd. ("Chugai") [Head Office: Chuo-ku, Tokyo; President Osamu Nagayama] announced that the company filed a new drug application (NDA) for R744, a long-acting erythropoiesis-stimulating agent, for the treatment of anemia associated with chronic kidney disease (renal anemia) with the Japanese Ministry of Health, Labour and Welfare (MHLW) today.
Renal anemia is one of the most frequent complications with chronic kidney disease (CKD), with significant impact on patients' quality of life. R744 is a continuous erythropoietin receptor activator which has a different interaction on the receptor level compared to other erythropoiesis stimulating agents. It was launched outside Japan in 2007 under the product name Mircera® as an innovative anti-anemia medication that allows a once-monthly maintenance therapy. With its extended dosing frequency compared to existing therapies, the product is contributing to the advancement of the management of renal anemia overseas.
Chugai conducted clinical trials for R744 in renal anemia patients in Japan. The results of these studies confirmed its efficacy and tolerability in CKD patients with once-every-four-week intravenous or subcutaneous dosing in maintenance therapy, which led to the filing today.
In recent years, there has been a significant increase in CKD patients with underlying diabetes. The increasing prevalence of CKD raises awareness of the importance of earlier treatment of anemia and simplified anemia management in these patients. To support treatment, guidelines have been issued by the Japanese Society for Dialysis Therapy and the Japanese Society of Nephrology in 2008 and 2009, respectively.
The area of renal diseases is one of the strategic focus areas for Chugai. Chugai will continue to focus on obtaining marketing authorization for R744 to make this new treatment option available for anemic patients with CKD and medical professionals in addition to the currently available standard therapy, the recombinant human erythropoietin EpoginR.
About R744R744 is a long-acting erythropoiesis stimulating agent (ESA) which has the longest serum half-life among ESAs on the market. The long serum half-life of R744 allows maintenance of hemoglobin level with once-every-four-week dosing for CKD patients, offering simplified anemia management and improved convenience for patients and caregivers. R744 is marketed outside Japan under the product name Mircera®.
Sunday, July 12, 2009
Hair test can spot terrorist
http://www.guardian.co.uk/uk/2009/jul/12/hair-tests-spot-terrorist
- Scientists have devised a hair test that the government hopes will help check the alibis of terrorist suspects and asylum seekers. They believe new laser scans of individual hair strands can reveal where a person has been living for the previous two months.
- Researchers at the National Metrology Institute in Teddington, Middlesex, have developed the laser to measure tiny changes in hair that are caused by diet or the immediate environment.
- The decision of the government to back the plans worries human rights groups, which believe that the tests could be easily abused.
- Each region across the world is believed to have a unique isotopic profile, reflected in the food, water and air particles. Anyone who visits a specific region is thought to absorb elements from the immediate environment.
Obesity health risk cause 'found'
http://news.bbc.co.uk/2/hi/health/8136820.stm
Scientists believe they may have uncovered a key reason why obese people have a raised risk of health complications such as type 2 diabetes.
- They blame a specific protein - pigment epithelium-derived factor (PEDF) - which is secreted by fat cells.
- The Australian and US research on mice suggests blocking some of PEDF's action may reverse some complications - raising hopes of new drug treatments.
- The study appears in the journal Cell Metabolism.
- The latest research shows that the protein sends a signal to other tissues in the body, triggering development of insulin resistance - a condition that often leads to type 2 diabetes - in the muscle and liver.
- Previous research had suggested that PEDF also protects against furring of the arteries and excessive blood vessel growth and helps keep the nervous system healthy.
Tuesday, July 7, 2009
Why You Need to Fail
http://blogs.harvardbusiness.org/bregman/2009/07/why-you-need-to-fail.html
"Peter, I'd like you to stay for a minute after class." Calvin teaches my favorite body conditioning class at the gym. "What'd I do?" I asked him."It's what you didn't do."
"What didn't I do?""Fail." "You kept me after class for not failing?""This," he began to mimic my casual weight lifting style, using weights that were obviously too light, "is not going to get you anywhere. A muscle only grows if you work it till it fails. You need to use more challenging weights. You need to fail."Calvin's onto something.Every time I ask a room of executives to list the top five moments their career took a leap forward — not just a step, but a leap — failure is always on the list. For some it was the loss of a job. For others it was a project gone bad. And for others still it was the failure of a larger system, like an economic downturn, that required them to step up.Yet most of us spend a tremendous effort trying to avoid even the possibility of failure. According to Dr. Carol Dweck, professor at Stanford University, we have a mindset problem. Dweck has done a tremendous amount of research to understand what makes someone give up in the face of adversity versus strive to overcome it. It turns out the answer is deceptively simple. It's all in your head.If you believe that your talents are inborn or fixed, then you will try to avoid failure at all costs because failure is proof of your limitation. People with a fixed mindset like to solve the same problems over and over again. It reinforces their sense of competence. Children with fixed mindsets would rather redo an easy jigsaw puzzle than try a harder one. Students with fixed mindsets would rather not learn new languages. CEOs with fixed mindsets will surround themselves with people who agree with them. They feel smart when they get it right.But if you believe your talent grows with persistence and effort, then you seek failure as an opportunity to improve. People with a growth mindset feel smart when they're learning, not when they're flawless. Michael Jordan, arguably the world's best basketball player, has a growth mindset. Most successful people do. In high school he was cut from the basketball team but that obviously didn't discourage him: "I've missed more than 9,000 shots in my career, I've lost almost 300 games. Twenty-six times I've been trusted to take the game wining shot and missed. I've failed over and over and over again in my life. And that is why I succeed."If you have a growth mindset, then you use your failures to improve. If you have a fixed mindset, you may never fail, but neither do you learn or grow.
In business, we have to be discriminating about when we choose to challenge ourselves. In high risk, high leverage situations, it's better to stay within your current capability. In lower risk situations, where the consequences of failure are less, better to push the envelope. The important point is to know that pushing the envelope, that failing, is how you learn and grow and succeed. It's your opportunity. Here's the good news: you can change your success by changing your mindset. When Dweck trained children to view themselves as capable of growing their intelligence, they worked harder, more persistently, and with greater success on math problems they had previously abandoned as unsolvable. A growth mindset is the secret to maximizing potential. Want to grow your staff? Give them tasks above their ability. They don't think they could do it? Tell them you expect them to work at it for a while, struggle with it. That it will take more time than the tasks they're used to doing. That you expect they'll make some mistakes along the way. But you know they could do it.Want to increase your own performance? Set high goals where you have a 50-70% chance of success. According to Psychologist and Harvard researcher the late David McClelland, that's the sweet spot for high achievers. Then, when you fail half the time, figure out what you should do differently and try again. That's practice. And according to recent studies, 10,000 hours of that kind of practice will make you an expert in anything. No matter where you start.The next class I did with Calvin, I doubled the weight I was using. Yeah, that's right. Unfortunately, that gave me tendonitis in my elbow, which I'm nursing with rest and ice. Sometimes you can even fail when you're trying to fail.
"Peter, I'd like you to stay for a minute after class." Calvin teaches my favorite body conditioning class at the gym. "What'd I do?" I asked him."It's what you didn't do."
"What didn't I do?""Fail." "You kept me after class for not failing?""This," he began to mimic my casual weight lifting style, using weights that were obviously too light, "is not going to get you anywhere. A muscle only grows if you work it till it fails. You need to use more challenging weights. You need to fail."Calvin's onto something.Every time I ask a room of executives to list the top five moments their career took a leap forward — not just a step, but a leap — failure is always on the list. For some it was the loss of a job. For others it was a project gone bad. And for others still it was the failure of a larger system, like an economic downturn, that required them to step up.Yet most of us spend a tremendous effort trying to avoid even the possibility of failure. According to Dr. Carol Dweck, professor at Stanford University, we have a mindset problem. Dweck has done a tremendous amount of research to understand what makes someone give up in the face of adversity versus strive to overcome it. It turns out the answer is deceptively simple. It's all in your head.If you believe that your talents are inborn or fixed, then you will try to avoid failure at all costs because failure is proof of your limitation. People with a fixed mindset like to solve the same problems over and over again. It reinforces their sense of competence. Children with fixed mindsets would rather redo an easy jigsaw puzzle than try a harder one. Students with fixed mindsets would rather not learn new languages. CEOs with fixed mindsets will surround themselves with people who agree with them. They feel smart when they get it right.But if you believe your talent grows with persistence and effort, then you seek failure as an opportunity to improve. People with a growth mindset feel smart when they're learning, not when they're flawless. Michael Jordan, arguably the world's best basketball player, has a growth mindset. Most successful people do. In high school he was cut from the basketball team but that obviously didn't discourage him: "I've missed more than 9,000 shots in my career, I've lost almost 300 games. Twenty-six times I've been trusted to take the game wining shot and missed. I've failed over and over and over again in my life. And that is why I succeed."If you have a growth mindset, then you use your failures to improve. If you have a fixed mindset, you may never fail, but neither do you learn or grow.
In business, we have to be discriminating about when we choose to challenge ourselves. In high risk, high leverage situations, it's better to stay within your current capability. In lower risk situations, where the consequences of failure are less, better to push the envelope. The important point is to know that pushing the envelope, that failing, is how you learn and grow and succeed. It's your opportunity. Here's the good news: you can change your success by changing your mindset. When Dweck trained children to view themselves as capable of growing their intelligence, they worked harder, more persistently, and with greater success on math problems they had previously abandoned as unsolvable. A growth mindset is the secret to maximizing potential. Want to grow your staff? Give them tasks above their ability. They don't think they could do it? Tell them you expect them to work at it for a while, struggle with it. That it will take more time than the tasks they're used to doing. That you expect they'll make some mistakes along the way. But you know they could do it.Want to increase your own performance? Set high goals where you have a 50-70% chance of success. According to Psychologist and Harvard researcher the late David McClelland, that's the sweet spot for high achievers. Then, when you fail half the time, figure out what you should do differently and try again. That's practice. And according to recent studies, 10,000 hours of that kind of practice will make you an expert in anything. No matter where you start.The next class I did with Calvin, I doubled the weight I was using. Yeah, that's right. Unfortunately, that gave me tendonitis in my elbow, which I'm nursing with rest and ice. Sometimes you can even fail when you're trying to fail.
Monday, July 6, 2009
How to Prevent Diabetes
http://www.fitnessandfreebies.com/fitness/mcdiabetes.html
* Managing your insulin (controlling sugar sources)
* Eating small portions instead of "filling up" at meals
* Keeping your bodyfat percentage down (obesity is a high risk factor)
Let's take a closer look:
Diet
There is no one magic diet that works for everyone. Nor is there a single diet that works best for one individual over a long time. Pay attention to your genetics, and to your ethnic group's traditional foods. If you are African American, that does not mean overcooked vegetables or pork rinds. Such garbage came on the nutritional scene only recently, and is not a true ethnic food. The same is true for Italians who overdose on pepperoni pizza. Being Italian myself as, well as having enjoyed fantastic African cuisine, I can tell you there is a lot more to these diets than the recent introductions often associated with these cultural groups.
Except for Eskimos and a few other highly specialized ethnic groups, all diets must adhere to the same few macronutrient rules. For example:
* Eliminate as many processed carbohydrates as possible.
* Don't eat carbohydrates 2 hours before bedtime.
* Balance your fat/carbos/protein in a roughly 30-40-30 ratio (this is a guideline, not a hard and fast rule--it doesn't work for everyone).
* Eat at least 5 or 6 small meals a day.
* Always eat a high-protein breakfast.
Did you know that the peanuts offered on airlines are LESS fattening than the fat-free pretzels? It's true. Stay away from fat-free foods--they make your insulin levels do a yo-yo, and that makes you put on fat. Yuck. Worse, it sets the stage for adult-onset diabetes.
Do NOT eat white flour, bleached flour, enriched flour, or any other kind of wheat flour that is not whole wheat. The glycemic effects of such flours will work against you. Eat whole grain flours, and try to get a variety. Amaranth and soy are two good flours. Eat oat groats instead of oatmeal. In short, get your grains in the least-processed form you can. This holds true for everyone, regardless of genetics (unless you have a malabsorption problem). This one "trick" will help you keep your insulin level on an even keel, and that is paramount to diabetes prevention and management.
What also holds true for everyone is: drink lots of water! Fill a gallon jug twice a day, and make sure you drink all of it. Once you get as lean as you want to be, cut back to a single gallon if you want to. For added fat loss, drink chilled (but not super cold) water. Sodas do not count. Such beverages are extremely unhealthy, for reasons I won't cover here. However, I will say that if you want to get osteoporosis, soft drinks are for you. Soft drinks make for soft bones.
Make sure to eat at least 5 or 6 small meals a day, rather than one big one. Doing so levels out your insulin and your blood sugar. Forget about that full feeling. If you find yourself overeating out of anxiety or boredom, fix the underlying problem -- don't add to it by poor eating!
Exercise
You need to build muscle and burn fat. How many lean, muscular people do you know with diabetes? OK, so listen! Live the lean lifestyle, and you will be way ahead in the diabetes game. See: Exercise!
Walking is a great exercise. Do it every day, and you'll raise your metabolic rate, as well as level out your blood sugar. This means you will burn extra calories even while you are sitting in front of your computer or sleeping in your bed! Look at the ways you save calories, and then spend them instead. Take the stairs instead of the elevator. Park away from the door, instead of up close. Use a pushmower instead of a riding mower. Pay attention to what you do and think of how you can burn more calories while doing it.
* Managing your insulin (controlling sugar sources)
* Eating small portions instead of "filling up" at meals
* Keeping your bodyfat percentage down (obesity is a high risk factor)
Let's take a closer look:
Diet
There is no one magic diet that works for everyone. Nor is there a single diet that works best for one individual over a long time. Pay attention to your genetics, and to your ethnic group's traditional foods. If you are African American, that does not mean overcooked vegetables or pork rinds. Such garbage came on the nutritional scene only recently, and is not a true ethnic food. The same is true for Italians who overdose on pepperoni pizza. Being Italian myself as, well as having enjoyed fantastic African cuisine, I can tell you there is a lot more to these diets than the recent introductions often associated with these cultural groups.
Except for Eskimos and a few other highly specialized ethnic groups, all diets must adhere to the same few macronutrient rules. For example:
* Eliminate as many processed carbohydrates as possible.
* Don't eat carbohydrates 2 hours before bedtime.
* Balance your fat/carbos/protein in a roughly 30-40-30 ratio (this is a guideline, not a hard and fast rule--it doesn't work for everyone).
* Eat at least 5 or 6 small meals a day.
* Always eat a high-protein breakfast.
Did you know that the peanuts offered on airlines are LESS fattening than the fat-free pretzels? It's true. Stay away from fat-free foods--they make your insulin levels do a yo-yo, and that makes you put on fat. Yuck. Worse, it sets the stage for adult-onset diabetes.
Do NOT eat white flour, bleached flour, enriched flour, or any other kind of wheat flour that is not whole wheat. The glycemic effects of such flours will work against you. Eat whole grain flours, and try to get a variety. Amaranth and soy are two good flours. Eat oat groats instead of oatmeal. In short, get your grains in the least-processed form you can. This holds true for everyone, regardless of genetics (unless you have a malabsorption problem). This one "trick" will help you keep your insulin level on an even keel, and that is paramount to diabetes prevention and management.
What also holds true for everyone is: drink lots of water! Fill a gallon jug twice a day, and make sure you drink all of it. Once you get as lean as you want to be, cut back to a single gallon if you want to. For added fat loss, drink chilled (but not super cold) water. Sodas do not count. Such beverages are extremely unhealthy, for reasons I won't cover here. However, I will say that if you want to get osteoporosis, soft drinks are for you. Soft drinks make for soft bones.
Make sure to eat at least 5 or 6 small meals a day, rather than one big one. Doing so levels out your insulin and your blood sugar. Forget about that full feeling. If you find yourself overeating out of anxiety or boredom, fix the underlying problem -- don't add to it by poor eating!
Exercise
You need to build muscle and burn fat. How many lean, muscular people do you know with diabetes? OK, so listen! Live the lean lifestyle, and you will be way ahead in the diabetes game. See: Exercise!
Walking is a great exercise. Do it every day, and you'll raise your metabolic rate, as well as level out your blood sugar. This means you will burn extra calories even while you are sitting in front of your computer or sleeping in your bed! Look at the ways you save calories, and then spend them instead. Take the stairs instead of the elevator. Park away from the door, instead of up close. Use a pushmower instead of a riding mower. Pay attention to what you do and think of how you can burn more calories while doing it.
Friday, July 3, 2009
Parkinson's drugs show promise in resistant TB
http://www.reuters.com/article/healthNews/idUSTRE56202020090703?feedType=nl&feedName=ushealth1100
CHICAGO (Reuters) - Drugs used to treat Parkinson's disease show promise as a new way to stem the rise of drug-resistant forms of tuberculosis, U.S. researchers said on Thursday.
They said computer models and lab experiments suggest the drugs tolcapone or Tasmar made by Valeant Pharmaceuticals, and entacapone or Comtan made by Novartis AG have the potential to treat multiple-drug-resistant and extensively drug-resistant strains of TB.
Computer programs predicted the chemically similar drugs should interfere with the TB bacillus, and tests in lab dishes using the drug Comtan confirmed it, the researchers said.
About 1.8 million people die worldwide each year from tuberculosis and a third of the world's population -- 2 billion people -- is infected, according to the World Health Organization.
Many people unknowingly have latent infections that can turn active if their immune system becomes weakened with other infections, such as HIV.
The WHO says that of 9 million new TB cases annually, about 490,000 are multiple-drug resistant TB or MDR-TB and about 40,000 are extensively drug resistant or XDR-TB.
"Given the continuing emergence of M. tuberculosis strains that are resistant to all existing, affordable drug treatments, the development of novel, effective and inexpensive drugs is an urgent priority," said Sarah Kinnings, a graduate student at the University of California, San Diego, who led the study.
Kinnings and colleagues used computer models and lab experiments to look for established drugs that might be of use in treating resistant forms of TB.
They found that the active component in both Comtan and Tasmar -- which are used to boost the effectiveness of the Parkinson's drug levodopa -- can also block the multiple-drug resistant tuberculosis bacterium.
The drugs block a brain chemical called COMT, in turn stopping it from breaking down Parkinson's drugs. But their molecular structure also allows them to block a compound that TB bugs need to build their protective cell wall.
Tasmar can damage the liver but Comtan is safer and could be used against TB, said Philip Bourne of the University of California, San Diego, who worked on the study published in the Public Library of Science journal PLoS Computational Biology.
"We have computational and experimental data to support this repositioning," Bourne, a professor of pharmacology, said in a statement.
He said the drugs are known to be safe in humans, and lab tests suggest they may be effective at blocking the bacterium.
Globally, cases of drug-resistant tuberculosis are being recorded at the highest rates ever seen, according to the World Health Organization. They are a particular threat in Russia and other former Soviet republics, India, China and South Africa.
CHICAGO (Reuters) - Drugs used to treat Parkinson's disease show promise as a new way to stem the rise of drug-resistant forms of tuberculosis, U.S. researchers said on Thursday.
They said computer models and lab experiments suggest the drugs tolcapone or Tasmar made by Valeant Pharmaceuticals, and entacapone or Comtan made by Novartis AG have the potential to treat multiple-drug-resistant and extensively drug-resistant strains of TB.
Computer programs predicted the chemically similar drugs should interfere with the TB bacillus, and tests in lab dishes using the drug Comtan confirmed it, the researchers said.
About 1.8 million people die worldwide each year from tuberculosis and a third of the world's population -- 2 billion people -- is infected, according to the World Health Organization.
Many people unknowingly have latent infections that can turn active if their immune system becomes weakened with other infections, such as HIV.
The WHO says that of 9 million new TB cases annually, about 490,000 are multiple-drug resistant TB or MDR-TB and about 40,000 are extensively drug resistant or XDR-TB.
"Given the continuing emergence of M. tuberculosis strains that are resistant to all existing, affordable drug treatments, the development of novel, effective and inexpensive drugs is an urgent priority," said Sarah Kinnings, a graduate student at the University of California, San Diego, who led the study.
Kinnings and colleagues used computer models and lab experiments to look for established drugs that might be of use in treating resistant forms of TB.
They found that the active component in both Comtan and Tasmar -- which are used to boost the effectiveness of the Parkinson's drug levodopa -- can also block the multiple-drug resistant tuberculosis bacterium.
The drugs block a brain chemical called COMT, in turn stopping it from breaking down Parkinson's drugs. But their molecular structure also allows them to block a compound that TB bugs need to build their protective cell wall.
Tasmar can damage the liver but Comtan is safer and could be used against TB, said Philip Bourne of the University of California, San Diego, who worked on the study published in the Public Library of Science journal PLoS Computational Biology.
"We have computational and experimental data to support this repositioning," Bourne, a professor of pharmacology, said in a statement.
He said the drugs are known to be safe in humans, and lab tests suggest they may be effective at blocking the bacterium.
Globally, cases of drug-resistant tuberculosis are being recorded at the highest rates ever seen, according to the World Health Organization. They are a particular threat in Russia and other former Soviet republics, India, China and South Africa.
Birth weight appears associated with leukemia
http://www.reuters.com/article/healthNews/idUSTRE5616MC20090702?feedType=nl&feedName=ushealth1100
NEW YORK (Reuters Health) - There may be an association between high birth weight and an increased risk of overall leukemia and acute lymphoblastic leukemia (ALL). The increased risk of acute myeloid leukemia (AML) appears to be associated with the high and low extremes of birth weight.
"There is a growing body of evidence indicating that childhood leukemia is initiated in utero," the two study authors reported in the International Journal of Cancer.
Dr. Robert W. Caughey of the Harvard School of Public Health and Dr. Karin B. Michels of Brigham and Women's Hospital, Boston, conducted an analysis of 32 studies to examine the association between birth weight, childhood leukemia, plus ALL and AML, two common leukemia subtypes. Included in the analysis were 16,501 cases of all types of leukemia, 10,974 cases of ALL, and 1832 cases of AML.
Compared with normal birth weight, high birth weight was associated with a 35 percent overall increased risk of leukemia, a 23 percent increased risk of ALL and a 40 percent increased risk of AML.
For every 1000 gram increase in birth weight, the odds ratio for overall leukemia increased by 1.18.
While low birth weight was not associated with overall leukemia or ALL, there was an association between low birth weight and a 49 percent increased risk of AML.
"Our study supports the notion that childhood leukemia is likely to be initiated in utero," Michels said in an email interview with Reuters Health. "Birth weight is a marker for events during pregnancy that may have affected the risk for leukemia in the offspring."
"It will be important to investigate which factors may operate in utero that affect leukemia risk," Michels said. For example, leukemia risk may be affected by epigenetic factors, modifications to genes other than changes in the DNA sequence itself. Epigenetic modifications may include the addition of molecules, like methyl groups, to the DNA backbone and other factors that may indirectly influence the expression of the genome.
SOURCE: International Journal of Cancer, June 1, 2009.
NEW YORK (Reuters Health) - There may be an association between high birth weight and an increased risk of overall leukemia and acute lymphoblastic leukemia (ALL). The increased risk of acute myeloid leukemia (AML) appears to be associated with the high and low extremes of birth weight.
"There is a growing body of evidence indicating that childhood leukemia is initiated in utero," the two study authors reported in the International Journal of Cancer.
Dr. Robert W. Caughey of the Harvard School of Public Health and Dr. Karin B. Michels of Brigham and Women's Hospital, Boston, conducted an analysis of 32 studies to examine the association between birth weight, childhood leukemia, plus ALL and AML, two common leukemia subtypes. Included in the analysis were 16,501 cases of all types of leukemia, 10,974 cases of ALL, and 1832 cases of AML.
Compared with normal birth weight, high birth weight was associated with a 35 percent overall increased risk of leukemia, a 23 percent increased risk of ALL and a 40 percent increased risk of AML.
For every 1000 gram increase in birth weight, the odds ratio for overall leukemia increased by 1.18.
While low birth weight was not associated with overall leukemia or ALL, there was an association between low birth weight and a 49 percent increased risk of AML.
"Our study supports the notion that childhood leukemia is likely to be initiated in utero," Michels said in an email interview with Reuters Health. "Birth weight is a marker for events during pregnancy that may have affected the risk for leukemia in the offspring."
"It will be important to investigate which factors may operate in utero that affect leukemia risk," Michels said. For example, leukemia risk may be affected by epigenetic factors, modifications to genes other than changes in the DNA sequence itself. Epigenetic modifications may include the addition of molecules, like methyl groups, to the DNA backbone and other factors that may indirectly influence the expression of the genome.
SOURCE: International Journal of Cancer, June 1, 2009.
Will IVF work for a particular patient? The answer may be found in her blood
Contact: Mary Rice
mary@mrcommunication.org
31-020-544-5813
European Society for Human Reproduction and Embryology
Amsterdam, The Netherlands: For the first time, researchers have been able to identify genetic predictors of the potential success or failure of IVF treatment in blood. Dr. Cathy Allen, from the Rotunda Hospital, Dublin, Ireland, told the 25th annual conference of the European Society of Human Reproduction and Embryology today (Wednesday 1 July) that her research would help understand why IVF works for some patients but not for others.
Previous work in this area has looked at gene profiles in such tissues as the uterine lining, but Dr. Allen and her team chose to examine the gene expression patterns in RNA extracted from peripheral (circulating) blood, an easily accessible biological sample. Blood samples were taken at eight different stages during the period around conception and the early stages of the IVF cycle. Five of these samples came from women who achieved clinical pregnancies, three from those who had implantation failure, and three from subfertile women who conceived spontaneously. Analysis showed that 128 genes showed a more than two-fold difference in expression in early clinical pregnancy compared with a non-pregnant state.
The molecular pathways that were most over-represented in this expression were concerned with angiogenesis (the growth of new blood vessels), endothelin signalling (blood vessel constriction), inflammation, oxidative stress (damage to cell structures), vascular endothelial growth factor (signalling processes in blood vessel growth), and pyruvate metabolism (the supply of energy to cells). "All these processes are important in the achievement and maintenance of pregnancy," said Dr. Allen.
"We found that the gene expression profiles in blood of patients at the time of pituitary down-regulation showed interesting patterns of gene clustering. Over 200 genes were differentially expressed in patients who went on to achieve an IVF pregnancy compared with those who did not," she said.
The researchers found that the peripheral blood gene expression 'signature' (also known as the transcriptome) before IVF was predictive of IVF outcome. This finding demonstrates the power of high-dimensional technology in biomarker discovery, and highlights the potential for developing clinically useful tools, they say.
One of the most difficult decisions for patients who have had unsuccessful IVF treatments is whether they should undergo further attempts at IVF, or if there are ways to optimise chances of success. The researchers hope that the results generated by this work will lead to the development of a test to aid in IVF decision-making. They say that their work will help to identity biomarkers that can identify events occurring at implantation, the maintenance of pregnancy and successful or unsuccessful pregnancy outcome.
"IVF technology has advanced tremendously over the past three decades, yet success after IVF remains an unpredictable outcome," said Dr. Allen. "Our work will help understand whether the implantation of embryos is influenced by the constantly changing expression of human genes."
Previous studies in the field of gene-expression have focused on single genes as opposed to genome-wide screening of all the human genes with high density DNA microarrays, as used by Dr. Allen and her team. The advent of tools like microarrays that can simultaneously probe for up to 29,000 genes has radically changed scientific approaches to this type of research. "It's like looking at how a team of players perform together rather than focusing on the individual players," said Dr. Allen.
"We intend to look further at the most significant genes we have identified as being important in this field in order to be able to understand their exact biological role in reproductive function. We hope that our work will lead to the development of a clinically useful tool to help doctors counsel their patients in the difficult decision-making involved in IVF," she said.
mary@mrcommunication.org
31-020-544-5813
European Society for Human Reproduction and Embryology
Amsterdam, The Netherlands: For the first time, researchers have been able to identify genetic predictors of the potential success or failure of IVF treatment in blood. Dr. Cathy Allen, from the Rotunda Hospital, Dublin, Ireland, told the 25th annual conference of the European Society of Human Reproduction and Embryology today (Wednesday 1 July) that her research would help understand why IVF works for some patients but not for others.
Previous work in this area has looked at gene profiles in such tissues as the uterine lining, but Dr. Allen and her team chose to examine the gene expression patterns in RNA extracted from peripheral (circulating) blood, an easily accessible biological sample. Blood samples were taken at eight different stages during the period around conception and the early stages of the IVF cycle. Five of these samples came from women who achieved clinical pregnancies, three from those who had implantation failure, and three from subfertile women who conceived spontaneously. Analysis showed that 128 genes showed a more than two-fold difference in expression in early clinical pregnancy compared with a non-pregnant state.
The molecular pathways that were most over-represented in this expression were concerned with angiogenesis (the growth of new blood vessels), endothelin signalling (blood vessel constriction), inflammation, oxidative stress (damage to cell structures), vascular endothelial growth factor (signalling processes in blood vessel growth), and pyruvate metabolism (the supply of energy to cells). "All these processes are important in the achievement and maintenance of pregnancy," said Dr. Allen.
"We found that the gene expression profiles in blood of patients at the time of pituitary down-regulation showed interesting patterns of gene clustering. Over 200 genes were differentially expressed in patients who went on to achieve an IVF pregnancy compared with those who did not," she said.
The researchers found that the peripheral blood gene expression 'signature' (also known as the transcriptome) before IVF was predictive of IVF outcome. This finding demonstrates the power of high-dimensional technology in biomarker discovery, and highlights the potential for developing clinically useful tools, they say.
One of the most difficult decisions for patients who have had unsuccessful IVF treatments is whether they should undergo further attempts at IVF, or if there are ways to optimise chances of success. The researchers hope that the results generated by this work will lead to the development of a test to aid in IVF decision-making. They say that their work will help to identity biomarkers that can identify events occurring at implantation, the maintenance of pregnancy and successful or unsuccessful pregnancy outcome.
"IVF technology has advanced tremendously over the past three decades, yet success after IVF remains an unpredictable outcome," said Dr. Allen. "Our work will help understand whether the implantation of embryos is influenced by the constantly changing expression of human genes."
Previous studies in the field of gene-expression have focused on single genes as opposed to genome-wide screening of all the human genes with high density DNA microarrays, as used by Dr. Allen and her team. The advent of tools like microarrays that can simultaneously probe for up to 29,000 genes has radically changed scientific approaches to this type of research. "It's like looking at how a team of players perform together rather than focusing on the individual players," said Dr. Allen.
"We intend to look further at the most significant genes we have identified as being important in this field in order to be able to understand their exact biological role in reproductive function. We hope that our work will lead to the development of a clinically useful tool to help doctors counsel their patients in the difficult decision-making involved in IVF," she said.
Study Pinpoints Genetic Drivers of Lung Cancer’s Spread
http://www.hhmi.org/news/massague20090702.html
For the first time, researchers have cracked open a genetic playbook that lung cancer uses to seed deadly new tumors in the brain, bone marrow, and other organs. Lung cancer cells, it turns out, hijack a master cellular signal that normally directs the development of embryos and helps maintain stem cell populations. Once it controls this genetic megaphone, a rogue lung cancer cell can settle into a new environment and grow rapidly.
The research identifies a factor that “gives cells the extra impulse to go above and beyond just being tumor cells to becoming metastatic cells,” says study leader Joan Massagué, a Howard Hughes Medical Institute investigator at Memorial Sloan-Kettering Cancer Center in New York. Massagué and his colleagues published their findings online July 2, 2009, in the journal Cell.
Lung cancer is the deadliest cancer in the United States, killing more than 150,000 people each year. The disease is devastating because lung tumors are highly metastatic—sending out wayward cells that invade the brain, bone marrow, and other organs, where they often form new, deadly tumors. Unlike breast cancer and prostate cancer, lung cancer metastasizes quickly; within weeks of the primary tumor’s formation, cells break off and enter the bloodstream. Some of these cells seed new tumors in other organs.
But metastasis is poorly understood, and nobody knew how the colonizing lung cancer cells accomplished their feat.
To find out, Massagué’s team genetically screened cells from 107 lung tumors that surgeons had removed from patients. Most of the tumors were early stage, excised before any metastasis had occurred in the patients. Physicians tracked all of the patients to determine if metastases ever appeared.
Massagué and his colleagues scrutinized the samples for signatures of a specific type of gene activity—activity that could help a cell integrate into a new environment and begin growing. Over the past two decades, various researchers have identified many genes that can help cells do this; most are involved in one of six pathways—flowchart-like sequences of genes that roust a cell to perform a high-level function, such as moving or dividing.
“We decided to ask if any of these pathways might be active in the tumors that went on to metastasize, but were not so active in those tumors that didn’t metastasize, where the patient was saved,” Massagué says.
His screen highlighted genes involved in one such pathway, called the WNT pathway. Certain WNT genes were turned on in tumors that eventually metastasized, but inactive in quiescent tumors.
“We were surprised,” says Massagué. “WNT is an important pathway in stem cell biology, in embryo development, and in the maintenance of adult tissues, such as the mucosa of the gut. And, in fact, colon cancer often begins when the WNT pathway becomes mutated. But no one had seen WNT activity in lung cancer. In fact, other research had ruled out the WNT pathway as an initiator of lung cancer.”
To see if the results accurately reflected tumor behavior, Massagué devised a second series of experiments. His team extracted cells from two different lung tumors, grew the cells, and injected them into mice. They then watched the animals, looking for those that rapidly developed metastases in the brain and bone marrow. The team extracted cells from the metastatic sites and compared them to the cells they had started with. Again, they found that the WNT pathway was overactive in the aggressive cells.
Next, the team artificially suppressed the activity of the WNT pathway in the aggressive cells and injected them back into mice. This reined in the cells, and they formed very few metastases.
“These independent lines of evidence all point to WNT as the mediator of the ability to metastasize,” says Massagué. “The tumor cells have hijacked this whole pathway because it provides them an advantage when metastasizing.”
The researchers then drilled down into the WNT pathway, which involves dozens of different genes, to search for the specific genes involved in lung metastasis. They found two, LEF1 and HOXB9, that were hyperactive in the metastatic cells. When they impeded the activity of these two genes, the previously metastatic cells languished, unable to form new tumors. These two genes act as “middle managers,” says Massagué, orchestrating other genes to perform complex cellular behaviors such as cell division, growth, and movement. Exactly how they get activated in lung cancer remains unknown, but this is a question that Don Nguyen, a Memorial Sloan Kettering colleague, is trying to answer.
Massagué hopes drug developers will now search for compounds that block the activity of the WNT pathway and then test whether such drugs will stanch metastases in patients.
In the meantime, he’s happy to have opened a biological black box. For too long, he says, cancer researchers shied away from studying the genetics of metastasis, thinking the problem too tough to crack. But in May, Massagué published another paper, in Nature, highlighting specific genes that help breast cancer metastasize.
“We no longer need to be afraid, as investigators, that metastasis is too difficult to study,” he says. “This is not true anymore. We've shown it's possible to break the problem open.”
For the first time, researchers have cracked open a genetic playbook that lung cancer uses to seed deadly new tumors in the brain, bone marrow, and other organs. Lung cancer cells, it turns out, hijack a master cellular signal that normally directs the development of embryos and helps maintain stem cell populations. Once it controls this genetic megaphone, a rogue lung cancer cell can settle into a new environment and grow rapidly.
The research identifies a factor that “gives cells the extra impulse to go above and beyond just being tumor cells to becoming metastatic cells,” says study leader Joan Massagué, a Howard Hughes Medical Institute investigator at Memorial Sloan-Kettering Cancer Center in New York. Massagué and his colleagues published their findings online July 2, 2009, in the journal Cell.
Lung cancer is the deadliest cancer in the United States, killing more than 150,000 people each year. The disease is devastating because lung tumors are highly metastatic—sending out wayward cells that invade the brain, bone marrow, and other organs, where they often form new, deadly tumors. Unlike breast cancer and prostate cancer, lung cancer metastasizes quickly; within weeks of the primary tumor’s formation, cells break off and enter the bloodstream. Some of these cells seed new tumors in other organs.
But metastasis is poorly understood, and nobody knew how the colonizing lung cancer cells accomplished their feat.
To find out, Massagué’s team genetically screened cells from 107 lung tumors that surgeons had removed from patients. Most of the tumors were early stage, excised before any metastasis had occurred in the patients. Physicians tracked all of the patients to determine if metastases ever appeared.
Massagué and his colleagues scrutinized the samples for signatures of a specific type of gene activity—activity that could help a cell integrate into a new environment and begin growing. Over the past two decades, various researchers have identified many genes that can help cells do this; most are involved in one of six pathways—flowchart-like sequences of genes that roust a cell to perform a high-level function, such as moving or dividing.
“We decided to ask if any of these pathways might be active in the tumors that went on to metastasize, but were not so active in those tumors that didn’t metastasize, where the patient was saved,” Massagué says.
His screen highlighted genes involved in one such pathway, called the WNT pathway. Certain WNT genes were turned on in tumors that eventually metastasized, but inactive in quiescent tumors.
“We were surprised,” says Massagué. “WNT is an important pathway in stem cell biology, in embryo development, and in the maintenance of adult tissues, such as the mucosa of the gut. And, in fact, colon cancer often begins when the WNT pathway becomes mutated. But no one had seen WNT activity in lung cancer. In fact, other research had ruled out the WNT pathway as an initiator of lung cancer.”
To see if the results accurately reflected tumor behavior, Massagué devised a second series of experiments. His team extracted cells from two different lung tumors, grew the cells, and injected them into mice. They then watched the animals, looking for those that rapidly developed metastases in the brain and bone marrow. The team extracted cells from the metastatic sites and compared them to the cells they had started with. Again, they found that the WNT pathway was overactive in the aggressive cells.
Next, the team artificially suppressed the activity of the WNT pathway in the aggressive cells and injected them back into mice. This reined in the cells, and they formed very few metastases.
“These independent lines of evidence all point to WNT as the mediator of the ability to metastasize,” says Massagué. “The tumor cells have hijacked this whole pathway because it provides them an advantage when metastasizing.”
The researchers then drilled down into the WNT pathway, which involves dozens of different genes, to search for the specific genes involved in lung metastasis. They found two, LEF1 and HOXB9, that were hyperactive in the metastatic cells. When they impeded the activity of these two genes, the previously metastatic cells languished, unable to form new tumors. These two genes act as “middle managers,” says Massagué, orchestrating other genes to perform complex cellular behaviors such as cell division, growth, and movement. Exactly how they get activated in lung cancer remains unknown, but this is a question that Don Nguyen, a Memorial Sloan Kettering colleague, is trying to answer.
Massagué hopes drug developers will now search for compounds that block the activity of the WNT pathway and then test whether such drugs will stanch metastases in patients.
In the meantime, he’s happy to have opened a biological black box. For too long, he says, cancer researchers shied away from studying the genetics of metastasis, thinking the problem too tough to crack. But in May, Massagué published another paper, in Nature, highlighting specific genes that help breast cancer metastasize.
“We no longer need to be afraid, as investigators, that metastasis is too difficult to study,” he says. “This is not true anymore. We've shown it's possible to break the problem open.”
Thursday, July 2, 2009
Genetically Engineered Mice Yield Clues to 'Knocking Out' Cancer
http://www.newswise.com/articles/view/553923/?sc=mwhn
Newswise — Deleting two genes in mice responsible for repairing DNA strands damaged by oxidation leads to several types of tumors, providing additional evidence that such stress contributes to the development of cancer. That’s the conclusion of a recent study* in DNA Repair by researchers at the National Institute of Standards and Technology (NIST), Oregon Health and Science University (OHSU) and the New York University School of Medicine (NYUSM).
Although all cells need oxygen to survive, the element also can be stressful to cells and their components—particularly DNA—as part of “reactive species” in the environment, such as free radicals and peroxides. The damage levied on DNA by these compounds can include lesions, breaks, cross-links and deletions—errors in our normal genetic codes that, if left unchecked, may accelerate the aging process and increase susceptibility to several disease states. In humans, DNA repair genes produce enzymes called DNA glycosylases that excise sections of DNA strands already modified by oxidative stress, and thus protect the genetic material.
One of these repair genes, neil1, was identified and characterized in 2002 by Sankar Mitra and his team at the University of Texas Medical Branch in collaboration with NIST researchers Miral Dizdaroglu and Pawel Jaruga. The gene produces a DNA repair protein, NEIL1 that is nearly identical in humans and mice. Therefore, a mouse serves a perfect model for studying the biological function of the neil1 gene in both species.
To do this, OHSU researchers under R. Stephen Lloyd genetically engineered mice without the neil1 gene (known as neil1 knockout mice). During their first 6-10 months of life, the majority of male mice developed severe obesity, dyslipidemia (abnormal levels of lipids in the blood), fatty liver disease and hyperinsulinemia (excess levels of circulating insulin in the blood). In humans, these disorders are collectively known as metabolic syndrome, a condition that affects more than 40 million persons in the United States.
In collaboration with Dr. Lloyd’s group, a second research team under George W. Teebor at NYUSM engineered mice that were missing either the neil1 or the nth1 gene (nth1 encodes for another DNA glycosylase, the NTH1 protein) or both these genes. These latter are known as neil1/nth1 double knockouts. NIST’s Dizdaroglu and guest researchers Pawel Jaruga and Güldal Kirkali found that both types of knockout mice exhibited significant accumulation of two lesions called formamidopyrimidines in the DNA of the liver, kidney and brain. This indicates that there was a lack of DNA repair in these organs.
During the second year of life, both types of mice also developed pulmonary and hepatocellular (liver cell) tumors. Double knockout mice had a higher incidence of tumors than the single knockouts.
The researchers state that their results emphasize the role of DNA repair in preventing carcinogenesis. The work may lead to the development of new measurement methods and reference materials for accurate and reproducible assessments of DNA damage and repair and contribute to understanding the role of oxidatively induced DNA damage and its repair in carcinogenesis. Future studies will focus on the role of NEIL1 in disease processes.
Newswise — Deleting two genes in mice responsible for repairing DNA strands damaged by oxidation leads to several types of tumors, providing additional evidence that such stress contributes to the development of cancer. That’s the conclusion of a recent study* in DNA Repair by researchers at the National Institute of Standards and Technology (NIST), Oregon Health and Science University (OHSU) and the New York University School of Medicine (NYUSM).
Although all cells need oxygen to survive, the element also can be stressful to cells and their components—particularly DNA—as part of “reactive species” in the environment, such as free radicals and peroxides. The damage levied on DNA by these compounds can include lesions, breaks, cross-links and deletions—errors in our normal genetic codes that, if left unchecked, may accelerate the aging process and increase susceptibility to several disease states. In humans, DNA repair genes produce enzymes called DNA glycosylases that excise sections of DNA strands already modified by oxidative stress, and thus protect the genetic material.
One of these repair genes, neil1, was identified and characterized in 2002 by Sankar Mitra and his team at the University of Texas Medical Branch in collaboration with NIST researchers Miral Dizdaroglu and Pawel Jaruga. The gene produces a DNA repair protein, NEIL1 that is nearly identical in humans and mice. Therefore, a mouse serves a perfect model for studying the biological function of the neil1 gene in both species.
To do this, OHSU researchers under R. Stephen Lloyd genetically engineered mice without the neil1 gene (known as neil1 knockout mice). During their first 6-10 months of life, the majority of male mice developed severe obesity, dyslipidemia (abnormal levels of lipids in the blood), fatty liver disease and hyperinsulinemia (excess levels of circulating insulin in the blood). In humans, these disorders are collectively known as metabolic syndrome, a condition that affects more than 40 million persons in the United States.
In collaboration with Dr. Lloyd’s group, a second research team under George W. Teebor at NYUSM engineered mice that were missing either the neil1 or the nth1 gene (nth1 encodes for another DNA glycosylase, the NTH1 protein) or both these genes. These latter are known as neil1/nth1 double knockouts. NIST’s Dizdaroglu and guest researchers Pawel Jaruga and Güldal Kirkali found that both types of knockout mice exhibited significant accumulation of two lesions called formamidopyrimidines in the DNA of the liver, kidney and brain. This indicates that there was a lack of DNA repair in these organs.
During the second year of life, both types of mice also developed pulmonary and hepatocellular (liver cell) tumors. Double knockout mice had a higher incidence of tumors than the single knockouts.
The researchers state that their results emphasize the role of DNA repair in preventing carcinogenesis. The work may lead to the development of new measurement methods and reference materials for accurate and reproducible assessments of DNA damage and repair and contribute to understanding the role of oxidatively induced DNA damage and its repair in carcinogenesis. Future studies will focus on the role of NEIL1 in disease processes.
Next-generation tag sequencing for cancer gene expression profiling
Canada's Michael Smith Genome Sciences Centre
1. E-mail: mmarra{at}bcgsc.ca
We describe a new method, Tag-seq, which employs ultra high-throughput sequencing of 21 base-pair cDNA tags for sensitive and cost-effective gene expression profiling. We compared Tag-seq data to LongSAGE data and observed improved representation of several classes of rare transcripts, including transcription factors, antisense transcripts and intronic sequences, the latter possibly representing novel exons or genes. We observed increases in the diversity, abundance, and dynamic range of such rare transcripts and took advantage of the greater dynamic range of expression to identify, in cancers and normal libraries, altered expression ratios of alternative transcript isoforms. The strand-specific information of Tag-seq reads further allowed us to detect altered expression ratios of sense and antisense (S-AS) transcripts between cancer and normal libraries. S-AS transcripts were enriched in known cancer genes, while transcript isoforms were enriched in miRNA targeting sites. We found that transcript abundance had a stronger GC-bias in LongSAGE than Tag-seq, such that AT-rich tags were less abundant than GC-rich tags in LongSAGE. Tag-seq also performed better in gene discovery, identifying over 98% of genes detected by LongSAGE, and profiling a distinct subset of the transcriptome characterized by AT-rich genes, which was expressed at levels below those detectable by LongSAGE. Overall, Tag-seq is sensitive to rare transcripts, has less sequence composition bias relative to LongSAGE, and allows differential expression analysis for a greater range of transcripts, including transcripts encoding important regulatory molecules.
Footnotes
*
o Received March 31, 2009.
o Accepted June 4, 2009.
* Copyright © 2009, Cold Spring Harbor Laboratory Press
1. E-mail: mmarra{at}bcgsc.ca
We describe a new method, Tag-seq, which employs ultra high-throughput sequencing of 21 base-pair cDNA tags for sensitive and cost-effective gene expression profiling. We compared Tag-seq data to LongSAGE data and observed improved representation of several classes of rare transcripts, including transcription factors, antisense transcripts and intronic sequences, the latter possibly representing novel exons or genes. We observed increases in the diversity, abundance, and dynamic range of such rare transcripts and took advantage of the greater dynamic range of expression to identify, in cancers and normal libraries, altered expression ratios of alternative transcript isoforms. The strand-specific information of Tag-seq reads further allowed us to detect altered expression ratios of sense and antisense (S-AS) transcripts between cancer and normal libraries. S-AS transcripts were enriched in known cancer genes, while transcript isoforms were enriched in miRNA targeting sites. We found that transcript abundance had a stronger GC-bias in LongSAGE than Tag-seq, such that AT-rich tags were less abundant than GC-rich tags in LongSAGE. Tag-seq also performed better in gene discovery, identifying over 98% of genes detected by LongSAGE, and profiling a distinct subset of the transcriptome characterized by AT-rich genes, which was expressed at levels below those detectable by LongSAGE. Overall, Tag-seq is sensitive to rare transcripts, has less sequence composition bias relative to LongSAGE, and allows differential expression analysis for a greater range of transcripts, including transcripts encoding important regulatory molecules.
Footnotes
*
o Received March 31, 2009.
o Accepted June 4, 2009.
* Copyright © 2009, Cold Spring Harbor Laboratory Press
How to Prevent Nose Bleeds
From Wiki How to
Besides from an injury, nosebleeds can be caused by low humidity in your home or office, colds and allergies, low levels of vitamin K, chronic sinusitis, medications (especially aspirin and blood thinners), high altitudes, excessive heat and blowing or picking the nose, and is a possible symptom of hypertension.
In younger people, especially, nosebleeds occur when blood vessels at the front of the septum - the cartilage that divides the nose - which are thin and fragile, rupture.
Steps
- If you are prone to nosebleeds, check the humidity in your house, and increase it to the normal range. Keep the heat low (60-64 degrees) in your bedroom.
- Keep nostrils moist. Take a shower and breathe deeply to get moisture into your nose. Then put petroleum jelly on the inside of the nose to keep it moist. A saline solution spray will also help.
- Limit blood thinners. Aspirin, vitamin E, Coumadin, heparin, garlic, ginger and ginseng are blood thinners. If you must use blood thinners, inform your doctor about the nosebleeds.
- Daily consumption of citrus fruit can help eliminate recurring nosebleeds. The bioflavonoids (a class of antioxidants) found in the fruit, seem to help with the prevention. Bioflavonoids help strengthen the blood vessels which makes them less likely to rupture. Take 500 mg of bioflavonoids twice a day if you do not eat several servings of fruit daily.
- Avoid foods that may give you a severe allergic reaction, such as milk and wheat.
- Putting a few drops of castor oil, vitamin E or zinc oxide in your nose each day will prevent recurring nosebleeds.
- Avoid spicy foods and fried foods.
- Don't scratch your nose very hard, especially if the inside is sensitive, or your nose is very dry.
Tips
- First words of wisdom: "Don't lie down!" Always keep your head elevated and above your heart. Breathe through your mouth.
- Sit up straight and tip your head slightly forward. Tilting the head back may cause the blood to run down the throat.
- Stay quiet for a few hours after the bleeding has stopped as exertion may cause the bleeding to start again.
- Before you try to stop the nosebleed, blow your nose hard. This will remove any clots which are keeping the blood vessel open. After getting the clot out the elastic fibers surrounding the vessel will contract around the tiny opening.
- Don't blow your nose for at least twelve hours after the bleeding has stopped.
- Use an ice pack on the nose. Cold causes blood vessels to constrict, reducing blood flow, swelling and inflammation.
- An ice pack or cold compress on the back of the neck is another remedy. Pressure on the back of the neck restricts flow of blood to the head.
- Press your finger between your lip and gum, pressing upward against the nose. Variations of this remedy are to place a rolled up piece of a brown paper bag, paper towel or gauze, a dime, or a tree leaf in the same position. There is a blood vessel that runs under the upper lip, and these techniques cut down the blood flow and allow the blood to clot.
- Using almost the same technique as above, press the outside of the upper lip just below the nose with your thumb and forefinger and hold for several minutes. This is a vital acupressure point in traditional Chinese medicine.
- For some, pinching the bridge of the nose helps close off the blood vessels. Using a cold compress or ice helps, as the blood vessels constrict faster. This should stop the bleeding in 3-5 minutes.
- After your nosebleed has stopped, use a cotton swab to apply an antibiotic ointment to the inside of your nose. This will kill bacteria and keep your nose moist. Reapply several times, especially before bedtime, for several days.
Warnings
- Call your doctor:
- If you have blood flowing from both nostrils.
- If the bleeding hasn't stopped after 30 minutes of pressure.
- If blood runs down the back of your throat even when the nose is pinched.
- If the nose is deformed from an injury.
- If nosebleeds reoccur several times during the day, or for several days in succession. This could be a symptom of a serious underlying ailment.
- If blood comes from the corner of your eye (tear duct).
- If you also experience chronic nasal blockage.
Profiling the T-cell receptor beta-chain repertoire by massively parallel sequencing
Copyright © 2009, Cold Spring Harbor Laboratory Press
T-cell receptor (TCR) genomic loci undergo somatic V(D)J recombination, plus the addition/subtraction of non-templated bases at recombination junctions, in order to generate the repertoire of structurally diverse T-cells necessary for antigen recognition. TCR beta subunits can be unambiguously identified by their hypervariable CDR3 (Complement Determining Region 3) sequence. This is the site of V(D)J recombination encoding the principal site of antigen contact. The complexity and dynamics of the T cell repertoire remain unknown because the potential repertoire size has made conventional sequence analysis intractable. Here, we use 5'RACE, Illumina sequencing, and a novel short read assembly strategy to sample CDR3β diversity in human T lymphocytes from peripheral blood. Assembly of 40.5 million short reads identified 33,664 distinct TCRβ clonotypes and provides precise measurements of CDR3β length diversity, usage of non-templated bases, sequence convergence, and preferences for TRBV and TRBJ gene usage and pairing. CDR3 length between conserved residues of TRBV and TRBJ ranged from 21 to 81 nt. TRBV gene usage ranged from 0.01% for TRBV17 to 24.6% for TRBV20-1. TRBJ gene usage ranged from 1.6% for TRBJ2-6 to 17.2% for TRBJ2-1. We identified 1,573 examples of convergence where the same amino acid translation was specified by distinct CDR3β nucleotide sequences. Direct sequence-based immunoprofiling will likely prove to be a useful tool for understanding repertoire dynamics in response to immune challenge, without a priori knowledge of antigen.
T-cell receptor (TCR) genomic loci undergo somatic V(D)J recombination, plus the addition/subtraction of non-templated bases at recombination junctions, in order to generate the repertoire of structurally diverse T-cells necessary for antigen recognition. TCR beta subunits can be unambiguously identified by their hypervariable CDR3 (Complement Determining Region 3) sequence. This is the site of V(D)J recombination encoding the principal site of antigen contact. The complexity and dynamics of the T cell repertoire remain unknown because the potential repertoire size has made conventional sequence analysis intractable. Here, we use 5'RACE, Illumina sequencing, and a novel short read assembly strategy to sample CDR3β diversity in human T lymphocytes from peripheral blood. Assembly of 40.5 million short reads identified 33,664 distinct TCRβ clonotypes and provides precise measurements of CDR3β length diversity, usage of non-templated bases, sequence convergence, and preferences for TRBV and TRBJ gene usage and pairing. CDR3 length between conserved residues of TRBV and TRBJ ranged from 21 to 81 nt. TRBV gene usage ranged from 0.01% for TRBV17 to 24.6% for TRBV20-1. TRBJ gene usage ranged from 1.6% for TRBJ2-6 to 17.2% for TRBJ2-1. We identified 1,573 examples of convergence where the same amino acid translation was specified by distinct CDR3β nucleotide sequences. Direct sequence-based immunoprofiling will likely prove to be a useful tool for understanding repertoire dynamics in response to immune challenge, without a priori knowledge of antigen.
Breast cancer: Metastasis on the brain
Nature Reviews Cancer 9, 460 - 461 (July 2009) | doi:10.1038/nrc2678
A new study shows that breast cancer metastasis to the brain usually occurs after metastasis to other organs because cells must be capable of not only general extravasation but also of passing through the blood-brain barrier.
A new study shows that breast cancer metastasis to the brain usually occurs after metastasis to other organs because cells must be capable of not only general extravasation but also of passing through the blood-brain barrier.
Breast cancer metastasis to the brain typically occurs after metastasis to other organs, possibly because the metastasizing cells must be capable of not only general extravasation but also of passing through the blood-brain barrier (BBB). Using gene expression analysis of breast cancer cells that exhibit specificity for brain colonization, Joan Massagué and colleagues present evidence that supports this hypothesis.
The authors inoculated immunodeficient female mice with two cell lines derived from patients with advanced breast cancer (CN34 and MDA-MB-231 cells) and then isolated populations of these cells that colonized the brain. After a second round of selection, they showed that these brain metastatic derivative (BrM2) cells had an increased ability to metastasize to the brain.
They identified 243 genes the expression of which was deregulated in both CN34-BrM2 and MDA-MB-231-BrM2 cells. Of these genes, the expression of 17 correlated with brain metastasis in a cohort of 368 patients with breast cancer. Interestingly, none of these 17 genes had previously been shown to be associated with bone, liver or lymph node metastases. However, 6 genes had been shown to correlate with lung metastasis. This supports previous studies that have shown an association between pulmonary and cerebral metastasis in breast cancer.
The authors focused on the shared genes encoding cyclooxygenase 2 (COX2) and epidermal growth factor receptor (EGFR) ligands (heparin-binding EGF (HBEGF) in the brain and epiregulin (EREG) in the lungs). COX2 synthesizes prostaglandin, which can increase BBB permeability, and short hairpin RNA (shRNA) against COX2 increased brain metastasis-free survival in mice injected with either of the BrM2 cell lines. EGFR and its ligands influence cell motility and invasion, and inhibition of EGFR with cetuximab also inhibited brain metastasis in mice. Furthermore, transmigration of the BrM2 cells in an in vitro model of the BBB was inhibited by COX2 shRNA, cetuximab or HBEGF shRNA. Given that brain metastases occur late in breast cancer progression, the authors tested the hypothesis that additional unique metastatic mediators could be upregulated to help cells pass through the BBB. A further 26 candidate genes were identified, and the authors focused their attention on a gene normally expressed only in the brain: the 
-2,6-sialyltransferase ST6GALNAC5. ST6GALNAC5 mRNA was increased in both BrM2 cell lines and in additional brain metastatic isolates. How might a sialyltransferase affect metastasis? These enzymes mediate sialylation, which is involved in cell-cell interactions. Indeed, the authors found that the adhesion of CN34-BrM2 cells to brain endothelial cells was inhibited by ST6GALNAC5 shRNA. These cells also exhibited reduced BBB transmigration in vitro and brain metastasis in mice, which was further reduced by cetuximab treatment. Moreover, expression of ST6GALNAC5 in an MDA-MB-231 derivative cell line that normally metastasizes to the lungs increased in vitro BBB transmigration and brain infiltration in mice.
These data shed some light on the poorly understood mechanisms that underlie breast cancer metastasis to the brain. It is hoped that further study of these and other genes associated with brain metastasis will provide candidate therapeutic targets.
MS: A New Theory for Why Repair of the Brain’s Wiring Fails
http://www.hhmi.org/news/rowitch20090701.html
- Scientists have uncovered new evidence suggesting that damage to nerve cells in people with multiple sclerosis (MS) accumulates because the body’s natural mechanism for repairing the nerve coating called myelin stalls out.
- The new research, published by Howard Hughes Medical Institute investigator David H. Rowitch and colleagues in the July 2009 issue of the journal Genes & Development, shows that repair of nerve fibers is hampered by biochemical signals that inhibit cellular repair workers in the brain, called oligodendrocytes.
- The symptoms of MS, which range from tingling and numbness in the limbs to loss of vision and paralysis, develop when nerve cells lose their ability to transmit a signal. Axons, which are the fibrous cables radiating from nerve cells, transmit impulses to neighboring neurons. They are dependent on myelin, which protects nerve cells and helps transmit their electrical signals properly.
- In people with MS, immune cells attack and erode this protective layer of myelin. In the early stages of the disease, damage accumulates in the myelin sheath only, but it does not affect the nerve cells themselves. Later on, axons without myelin and the nerve cells themselves die.
- Although damaged myelin can usually be repaired, in some people with MS the repair effort is inefficient, said Rowitch, who is at the University of California, San Francisco. This could be because oligodendrocytes themselves might not work properly, or they may be killed off by the disease. Rowitch explained that in chronically demyelinated areas of the central nervous system, oligodendrocyte precursor cells have been found, but they appear stalled in development and never become fully functional oligodendrocytes.
- Rowitch and his team set out to see if they could determine what was slowing down myelin repair. With colleagues at UCSF and the University of Cambridge in England, Rowitch destroyed a small region of white matter in the spinal cords of healthy mice, then monitored the repair process, examining the tissue after five, 10, and 14 days.
- To find out which genes were contributing to three key stages in the repair process – the recruitment of oligodendrocyte precursors to the site of injury, the maturation of those cells into functional oligodendrocytes, and the formation of a new myelin sheath -- the researchers measured the activity of 1,040 genes. All of the genes they studied encode transcription factors, which regulate the activity of other genes. Their experiments showed that 50 transcription factors are working during key steps in myelin repair.
- “They turned on and off at particular time points associated with recognized stages of the repair process, such as recruitment of repair cells back into the lesion, early differentiation [of the precursor cells into more specialized cells], and then myelin production,” said Rowitch.
- The team focused, in particular, on one of the genes called Tcf4. In damaged areas where repair attempts were under way, expression of Tcf4 was strong, Rowitch said.
- Tcf4 is involved in a cascade of biochemical events known as the W
- Scientists have uncovered new evidence suggesting that damage to nerve cells in people with multiple sclerosis (MS) accumulates because the body’s natural mechanism for repairing the nerve coating called myelin stalls out.
- The new research, published by Howard Hughes Medical Institute investigator David H. Rowitch and colleagues in the July 2009 issue of the journal Genes & Development, shows that repair of nerve fibers is hampered by biochemical signals that inhibit cellular repair workers in the brain, called oligodendrocytes.
- The symptoms of MS, which range from tingling and numbness in the limbs to loss of vision and paralysis, develop when nerve cells lose their ability to transmit a signal. Axons, which are the fibrous cables radiating from nerve cells, transmit impulses to neighboring neurons. They are dependent on myelin, which protects nerve cells and helps transmit their electrical signals properly. In people with MS, immune cells attack and erode this protective layer of myelin. In the early stages of the disease, damage accumulates in the myelin sheath only, but it does not affect the nerve cells themselves. Later on, axons without myelin and the nerve cells themselves die.
- Although damaged myelin can usually be repaired, in some people with MS the repair effort is inefficient, said Rowitch, who is at the University of California, San Francisco. This could be because oligodendrocytes themselves might not work properly, or they may be killed off by the disease. Rowitch explained that in chronically demyelinated areas of the central nervous system, oligodendrocyte precursor cells have been found, but they appear stalled in development and never become fully functional oligodendrocytes.
- Rowitch and his team set out to see if they could determine what was slowing down myelin repair. With colleagues at UCSF and the University of Cambridge in England, Rowitch destroyed a small region of white matter in the spinal cords of healthy mice, then monitored the repair process, examining the tissue after five, 10, and 14 days.
- To find out which genes were contributing to three key stages in the repair process – the recruitment of oligodendrocyte precursors to the site of injury, the maturation of those cells into functional oligodendrocytes, and the formation of a new myelin sheath -- the researchers measured the activity of 1,040 genes. All of the genes they studied encode transcription factors, which regulate the activity of other genes. Their experiments showed that 50 transcription factors are working during key steps in myelin repair.
- “They turned on and off at particular time points associated with recognized stages of the repair process, such as recruitment of repair cells back into the lesion, early differentiation [of the precursor cells into more specialized cells], and then myelin production,” said Rowitch.
- The team focused, in particular, on one of the genes called Tcf4. In damaged areas where repair attempts were under way, expression of Tcf4 was strong, Rowitch said.
- Tcf4 is involved in a cascade of biochemical events known as the Wnt (pronounced “wint”) pathway. While the pathway’s importance has been recognized in normal development of many tissues, including the brain, Rowitch said Wnt had never before been linked to myelin production or repair.
- To glean further evidence about Wnt’s role, the researchers hyperactivated the Wnt pathway in the oligodendrocytes of mice, testing whether this helped or hurt myelin repair. Doing so caused a profound delay in repair, Rowitch said. Upon further analysis, the researchers concluded that the Wnt pathway activation was creating a roadblock that prolonged oligodendrocyte precursor development.
- “These animals did eventually show repair,” Rowitch said, “but it was delayed by about 10 days compared to normal mice.” The researchers also tested human tissue for the presence of Tcf4, and found the protein in areas damaged by MS but not in healthy white matter. Further, the researchers examined available data from another study and found that many signaling molecules of the Wnt pathway are overactive in patients with MS.
- Rowitch’s team is starting to examine some of the other genes it found to be active in the myelin repair process, and is developing new mouse models to help test potential therapies that might manipulate the Wnt pathway to improve myelin repair. Given the pathway’s role in so many different processes, however, Rowitch cautioned that targeting Wnt could cause unintended side effects.
- The new work may also have implications in another disease Rowitch studies—periventricular leukomalacia (PVL), a deficiency of white matter around the brain’s ventricles, which connect to the central canal of the spinal cord. PVL usually occurs in extremely premature infants with brain injury, who often go on to develop cerebral palsy.
- Although scientists had previously believed PVL resulted when oligodendrocytes were killed off by stress or toxic injury, Rowitch and colleagues at Children’s Hospital in Boston recently found that, as in the MS study, oligodendrocyte precursors had been recruited to the site of white matter lesions and stood poised to repair the damage, but for some reason did not proceed.
- nt (pronounced “wint”) pathway. While the pathway’s importance has been recognized in normal development of many tissues, including the brain, Rowitch said Wnt had never before been linked to myelin production or repair.
- To glean further evidence about Wnt’s role, the researchers hyperactivated the Wnt pathway in the oligodendrocytes of mice, testing whether this helped or hurt myelin repair. Doing so caused a profound delay in repair, Rowitch said. Upon further analysis, the researchers concluded that the Wnt pathway activation was creating a roadblock that prolonged oligodendrocyte precursor development.
- “These animals did eventually show repair,” Rowitch said, “but it was delayed by about 10 days compared to normal mice.” The researchers also tested human tissue for the presence of Tcf4, and found the protein in areas damaged by MS but not in healthy white matter. Further, the researchers examined available data from another study and found that many signaling molecules of the Wnt pathway are overactive in patients with MS.
- Rowitch’s team is starting to examine some of the other genes it found to be active in the myelin repair process, and is developing new mouse models to help test potential therapies that might manipulate the Wnt pathway to improve myelin repair. Given the pathway’s role in so many different processes, however, Rowitch cautioned that targeting Wnt could cause unintended side effects.
- The new work may also have implications in another disease Rowitch studies—periventricular leukomalacia (PVL), a deficiency of white matter around the brain’s ventricles, which connect to the central canal of the spinal cord. PVL usually occurs in extremely premature infants with brain injury, who often go on to develop cerebral palsy.
- Although scientists had previously believed PVL resulted when oligodendrocytes were killed off by stress or toxic injury, Rowitch and colleagues at Children’s Hospital in Boston recently found that, as in the MS study, oligodendrocyte precursors had been recruited to the site of white matter lesions and stood poised to repair the damage, but for some reason did not proceed.
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