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Postuar nga NS-6 datė 08 Shkurt 2006 - 00:14:

Adult stem cells from knee fat turned into cartilage, bone, fat cells

Cod. A08022006

Adult stem cells from knee fat turned into cartilage, bone, fat cells
1.DALLAS-Duke University Medical Center researchers have "reprogrammed" adult stem cells taken from a small deposit of fat behind the kneecap into functioning cartilage, bone or fat cells that could potentially be grown into replacement tissues.

2.The research team, which reported last year that they were able to turn fat cells taken from liposuction procedures into functional cartilage cells, provides further evidence that stem cells taken from different adult sources have the potential to be transformed into multiple specialized cell types.

3."In scientific terms, we have found a new source of adult stem cells that can be changed into different cells and tissues," said M. Quinn Wickham, who presented the results of the Duke research today (Feb. 10) at the annual meeting of the Orthopedic Research Society. Wickham is a fourth-year medical student working in the laboratory of Farshid Guilak, director of orthopedic research at Duke and senior member of the research team.

4."On the clinical side, for example, it would be relatively easy for a knee surgeon to obtain some of these fat cells using a minimally invasive approach," Wickham continued. "We could then grow cartilage custom-made for the individual to repair an injury in the knee with the patient's own tissue."

5.The fat pad is a dense structure behind the patella, or kneecap, that is unlike typical fat tissue found throughout the body, the researchers said. While its function is not well understood, researchers do know that it is metabolized much more slowly than subcutaneous fat.

6."This is another demonstration that adult stem cells are not necessarily locked into their current fate, and furthermore, we can reprogram them into becoming other cell types," Guilak said. "It is unlikely that one source of stem cells can be used to treat the wide variety of medical problems and diseases, but different clinical problems could be addressed by using adult cells taken from different spots throughout the body, without the same ethical concerns associated with embryonic stem cells."

7.In the current study, the researchers took the fat pads from patients whose knee joints were removed during total joint replacement surgery. The researchers focused on specific cells within the samples known as adipose-derived stromal cells, which under normal situations would receive environmental cues to transform themselves into fat pad cells. After the samples were treated with a series of enzymes and centrifuged, the separated stromal cells were treated with a biochemical cocktail of different steroids and growth factors.

8."By treating these stromal cells with different agents, we were able to induce them to commit to multiple lineages," Wickham said. "These findings suggest that the fat pad, given its location and accessibility, may prove to be an excellent source of progenitor cells for tissue engineering or other cell-based therapies."

9.In addition to controlling their biochemical environment, the researchers were able to grow different cell types from the adult stem cells by controlling their shape in a three-dimensional matrix, a crucial advance for using resulting tissues as human therapies. To grow cartilage, groups of cells were infused into a matrix made of a substance known as alginate, a complex carbohydrate that is often used as the basis of bioabsorbable dressings.
The therapeutic potential for tissues grown from these adult stem cells is large and varied, Wickham said.

10."For example, fat tissue could be custom grown for use in reconstructive or cosmetic cases performed by plastic surgeons," Wickham said. "The bone tissue could be used to repair bone defects caused by disease or trauma." Since cartilage is a tissue type that is poorly supplied by blood vessels, nerves and the lymphatic system, it has a very limited capacity for repair when damaged. The researchers believe that this would be one of the earliest therapeutic uses of such tissue engineering techniques.

11."For patients with tissue damage, we envision being able to remove a small piece of fat, and then growing customized, three-dimensional pieces of tissue which would then be surgically implanted where needed," Guilak continued. "One of the beauties of this system is that since the cells are from the same patients, there are no worries of adverse immune responses or disease transmission. However, we would still like to test whether cells from a person's fat tissue could be used to treat another patient without being rejected."

12.Guilak estimated that it might be more than five years before this approach becomes a clinical reality. However, based on the results of numerous prior animal studies, and the results of the current experiments, the researchers are confident that this strategy has potential. Collaborating with the Duke team was Dr. Jeff Gimble of Durham, N.C.-based Artecel Sciences, who holds the patent for the process of isolating these cells from fat. Guilak is a consultant for Artecel Sciences.


Postuar nga NS-6 datė 08 Shkurt 2006 - 00:19:

Oxygen Key Switch In Transforming Adult Stem Cells From Fat Into Cartilage

Cod. B08022006

Oxygen Key Switch In Transforming Adult Stem Cells From Fat Into Cartilage

1.NEW ORLEANS -- In their ongoing research on turning adult stem cells isolated from fat into cartilage, Duke University Medical Center researchers have demonstrated that the level of oxygen present during the transformation process is a key switch in stimulating the stem cells to change.
Their findings were presented today (Feb. 2, 2003) at the annual meeting of the Orthopedic Research Society.

2.Using a biochemical cocktail of steroids and growth factors, the researchers have "retrained" specific adult stem cells that would normally form the structure of fat into another type of cell known as a chondrocyte, or cartilage cell. During this process, if the cells were grown in the presence of "room air," which is about 20 percent oxygen, the stem cells tended to proliferate; however, if the level of oxygen was reduced to 5 percent, the stem cells transformed into chondrocytes.

3.This finding is important, the researchers say, because this low oxygen level more closely simulates the natural conditions of cartilage, a type of connective tissue that cushions many joints throughout the body. However, since it is a tissue type poorly supplied by blood vessels, nerves and the lymphatic system, cartilage has a very limited capacity for repair when damaged. For this reason, the Duke investigators are searching for a bioengineering approach to correct cartilage injury.

4."Our findings suggest that oxygen is a key determinant between proliferation and differentiation, and that hypoxia, or low oxygen levels, is an important switch that tells cells to stop proliferating and start differentiating,' said David Wang, a fourth-year medical student at Duke, who presented the results of the Duke research.

5.Farshid Guilak, Ph.D., director of orthopedic research and senior member of the Duke team, said that the combination of growth factors sets the adult stem cells on the right path, while controlling oxygen levels inspires the cells to more readily transform into chondrocytes. Without the growth factors, he said, changing oxygen levels has no effect on the cells.

6."For us, the ultimate goal is the development of a bioreactor where we can very carefully control the physical and chemical environment of these cells as they transform," Guilak said. "The results of these experiments which demonstrated the role of oxygen levels in the process represent another important step in achieving this goal."

7.Two years ago at the Orthopedic Research Society meeting, the Duke team for the first time reported that cartilage cells can be created from fat removed during liposuction procedures. Not only were the researchers able to make cells change from one type into another, they grew the new chondrocytes in a three-dimensional matrix, a crucial advance for success in treating humans with cartilage damage.

8.In their latest experiments, the team used the materials collected from liposuction procedures performed on multiple human donors. These materials were then treated with enzymes and centrifuged until cells known as adipose-derived stromal cells remained. These isolated cells were infused into three-dimensional beads made up of a substance known as alginate, a complex carbohydrate that is often used as the basis of bioabsorbable dressings, and then treated with the biochemical cocktail.

9.Those cells grown in hypoxic conditions saw growth inhibited by as much as 44 percent, but saw as much as an 80 percent increase in chondrocyte differentiation.

"No one has looked at the role of hypoxia in the creation of chondrocytes, but it made sense since cartilage normally exists in an hypoxic environment," Wang said. "While we know oxygen plays a role, we don't know the mechanism. The next questions to answer are how the cells sense the level of oxygen around them and then turn that into a metabolic change."

10.The researchers anticipate that the first patients to benefit from this research would be those who have suffered some sort of cartilage damage due to injury or trauma. Farther down the line, they foresee a time when entire joints ravaged by osteoarthritis can be relined with bioengineered cartilage.

11."We don't currently have a satisfactory remedy for people who suffer a cartilage-damaging injury," Guilak said. "There is a real need for a new approach to treating these injuries. We envision being able to remove a little bit of fat, and then grow customized, three-dimensional pieces of cartilage that would then be surgically implanted in the joint. One of the beauties of this system is that since the cells are from the same patients, there are no worries of adverse immune responses or disease transmission."

The Duke researchers have developed several animal protocols to test how this cartilage fares in a living system.

p.s: maybe the news is a bit old but the information given seems interesting,so i brought it here...


Postuar nga NS-6 datė 12 Shkurt 2006 - 01:00:

Max Planck Researchers Discover A Protein Which Is Deadly For Anthrax Bacteria

Cod. C12022006

Source: Max Planck Society
Date: 2005-11-12

Max Planck Researchers Discover A Protein Which Is Deadly For Anthrax Bacteria
1.Scientists from the Max Planck Institute for Infection Biology in Berlin discovered why lung, but not skin, anthrax infections are lethal. As reported in the newest issue of PloS Pathogen (November 2005) Neutrophils, a form of white blood cells, play a key role in anthrax infections.

2.They can kill Bacillus anthracis by producing a protein called alpha-defensin. This discovery might now pave the way towards the development of new therapiesfor the fatal lung form of anthrax.

3.Bacillus anthracis is the causative agent of anthrax. What makes Bacillus anthracis especially dangerous is that these bacteria can form spores. The spores are extremely resistant against environmental stress and can survive for years.Infection with Bacillus anthracis can take place either via the lung or through the skin. Interestingly, the lung form of anthrax is almost always fatal, whereas skin infections remain localized and are rarely lethal. In contrast to the lung form, the skin form of anthrax can be treated without problems and most patients recover. During the past few years, Bacillus anthracis has also been used as a weapon for bioterrorism. Anthrax spores were sent in envelopes and inhaled and resulted in the death of 5 people in the USA.

4.The findings of the lab of Arturo Zychlinsky now help clarifying why the skin form is harmless in contrast to the lung form. After a skin infection with Bacillus anthracis, neutrophils are recruited to the site of infection. Neutrophils are white blood cells that can identify and kill microbes. In the skin, neutrophils take up the spores, which germinate inside the neutrophil to a vegetative ("growing") bacterium. This vegetative bacterium is then attacked and killed within the neutrophil. The scientists succeeded in identifying the substance responsible for the killing of the bacteria. After fractionation of neutrophil components only one protein remained which is sufficient for killing Bacillus anthracis: alpha-defensin

5.This mechanism is not effective in the lung form of anthrax. Here, the number of neutrophils recruited to the site of infection is known to be low, and insufficient to kill bacteria. Thus, inhaled spores can germinate and spread through the organism. The scientists in Berlin now hope that their discovery will help to develop new drugs against the lung form of anthrax. There might be the possibility that the inhalation of alphadefensin might kill vegetative bacteria in the lung and prevent dissemination.


Postuar nga NS-6 datė 13 Mars 2006 - 22:38:

New method to increase the efficiency of contrast radiology

Cod. A13032006

1.A new method to increase the efficiency of contrast radiology may open the way to earlier and more reliable diagnosis of, for example, breast cancer. With new integrated electronics and signal processing, the image quality can be improved sharply.
This was demonstrated by Hans Bornefalk at the Royal Institute of Technology as he presented his doctoral thesis about the technology on March 10.

2.To date, the new technology has only been tested in a test rig, but in principle it can open the way for earlier and more reliable diagnosis of, for example, breast cancer. In a long-term perspective, there are a number of other radiological applications in which contrast substances are used today.

3.To grow, a cancer needs to form its own blood vessels, which are often of poor quality and can leak. In contrast radiology, a contrast substance such as iodine is injected into the blood stream so that the blood vessels can be seen on the radiology images. Indirectly, then the cancer is also seen through the leakage in these blood vessels. Normally, a series of images is required to secure the contrast image.

4.With Hans Bornefalk's new method, one radiology image is sufficient to benefit from the contrast information. In addition, the image quality can be sharply improved or the ray dosage reduced. This is possible by being able to trace and register each X-ray separately. Since the X-rays can also be separated into two categories, in which one has higher and the other lower energy than the contrast substance's threshold value for maximum absorption energy, totally new possibilities emerge.

5."With the proper electronics, you can precisely separate the X-rays that are above and below this threshold value and highlight the differences between the blood vessels and surrounding tissue in a totally different manner," relates Hans Bornefalk. " Radiology examinations can be carried out quicker and more reliably and the risk for blurredness due to movement between images is eliminated."

6.Clinical tests are required to verify the new technology and maximize the clinical benefits. Sectra, a company that develops and manufactures equipment for radiology examinations, has plans to integrate the new technology into its future products.

7."This fits well into our mammography operations and will reinforce the world-leading position of Swedish industry in this area," says Jesper Söderqvist, President of Sectra Mamea in Kista.

In intense competition, Hans Bornefalk's work was recognized a few weeks ago as the "Best Student Contribution" at a major conference for medical radiology technology in San Diego, California, in the US.

p.s: numrat behen ne menyre qe kur ta lexoni te arrini nje perqendrim me i mire duke qene se artikujt e gjate mund te cojne edhe ne ngaterrese gjate leximit.


Postuar nga NS-6 datė 15 Mars 2006 - 22:57:

Statin drug reverses heart disease

Cod. B15032006

Published: Wednesday, 15-Mar-2006

1.Researchers say a high dose of a cholesterol-lowering statin drug can reverse the build-up of plaque in coronary arteries.
Such a build up can lead to a heart attack or stroke, and the researchers say this is the first time statins have been shown to have such an effect.

They say the changes in cholesterol levels seen in the study were the largest ever seen in a major trial of statin drugs.

2.A study of more than 500 patients found that after two years of treatment with a high dose of the cholesterol-lowering statin drug, Crestor, plaque volume was reduced by 7 to 9 percent.

The drug was also found to lower levels of LDL "bad" cholesterol by more than 53 percent to 60.8 and raised levels of HDL, or "good" cholesterol by nearly 15 percent to an average of 49.

3.Although Crestor is considered to be one of the most powerful statin drugs, concerns about the potential side effects such as muscle damage and kidney damage, especially among Asians,have somewhat tarnished it's reputation.

Just last year the U.S. Food and Drug Administration dismissed a petition by the consumer group Public Citizen to have Crestor banned.

The changes in cholesterol levels seen in the study were the largest ever seen in a major trial of statin drugs, say the researchers.

4.According to Dr. Steve Nissen, interim director of the department of cardiovascular medicine at the Cleveland Clinic and the study's lead author, "the results were shockingly positive".

5.The trial does however leave unanswered the question of whether less plaque means fewer heart attacks and strokes; Nissen says the study does indicate very low LDL levels along with raised HDL, can partially reverse heart disease.

Apparently the patients in the trial had not been treated previously with statins.

Other statin drugs such as Lipitor, Zocor and Vytorin, might also lead to similar plaque regression, says Nissen.

6.Atherosclerosis results when a build-up of cholesterol, inflammatory cells and fibrous tissue form areas in the artery wall called plaques.

If these plaques rupture, they can block blood flow to critical organs, such as the heart or brain, and can lead to heart attack or stroke.

7.Nissen said he doubted that a statin drug could reduce plaque by much more than the levels seen in the Crestor trial, which used the highest approved dose for the drug.

But some experts are cautious about the findings and say more study is needed.

Many regard lifestyle changes, such as eating a better diet, and exercising regularly as the key to managing cardiovascular disease.

8.Crestor is produced by drug company AstraZeneca who sponsored the trial.

The results were presented at a meeting of the American College of Cardiology in Atlanta.

The study will be published in the April edition of the Journal of the American Medical Association.


Postuar nga darke datė 21 Mars 2006 - 10:07:

Question Prolactina

Hello doctor!

How is going with your section? I see it is growing and growing. I have a question for you; it's about an hormon called PROLACTINA ("prolactina" is in Spanish, and I beg you pardom cause I don't know how it is written in English; maybe they both are seemed). So the question is: how does the prolactina affect to the body? and what happen when the level of this hormon is very high? what would be your diagnosis? :p

Ciao ciao. See you!

Kisses...


Postuar nga NS-6 datė 21 Mars 2006 - 22:09:

prolactina and its hyperproduction

Cod. B21032006

Hi there darkeeeee!!!Where have u been? How's the new generation going? Do they respect the teacher?...my section is growing every day...and i like that a lot

Now ur question:
Prolactina is a hormone produced by the pituitary gland and its major effect is seen in the women...mainly on the mammary gland. It stimulates the milk production... In fact when the baby sucks the mammary gland,there begins a response to this by producing prolactina that increases the milk production and release.

When the level of prolactina is high u have to consider the cause of this:
It may be physiological as in case of pregnancy when the level increases or it may be due to stress or physical activity.However except the first case which may be the most common as a physiological cause,mostly it is due to a pituitary adenoma.In fact prolactinoma is in first rank in the pituitary adenomas cases.The symptoms are menstruation cycle problems such as amenorrhea(no menstruation cycle) and also galactorrea (milk comes out from the nipples spontaneously or after a small pressure on it).these are the primary peripheral symptoms even why there might be other symptoms but they might be misunderstood because not very specific.there are also other symptoms due to the mass of the adenoma which varies from problems on the ocular nerve to the destruction of the remaining part of the pituitary gland due to the pressure on that part.
Diagnosis is based on symptoms like vision problems,cefalea or presence of amenorrhea or galatorrea (even why for these there are other test that will be done to verify other hypothesis). Prolactine concentration in plasma will be over the limits...i don't remember if there is another exam to measure the concentration of prolactina (i think there is smth with the thyroglobulin but i don't remember it very well)...if there is the suspect of an adenoma, MRN is the best to identify the location and the dimensions.

iIcant say u anything about the therapy becouse i dont know it ...i havent studied it...i may give u any information more if i search the book!
Up to then have a nice day...
And sorry for my english...as always it sucks...and it getS no milk from that

p.s: If any of u knows anything more,I'd invite em to write it down!


Postuar nga darke datė 22 Mars 2006 - 10:36:

Lightbulb Re: prolactina and its hyperproduction

miredita zoti ns-6!
si je? I've been very well and working hard. Well, about the new generation... I could say it's very predictable . At the begining they see you and they observe you with shyness but soon they start to have confidence, and here it's when darke has to show her eyeteeth Let me tell you what happened once... During some days everything was ok. I always have tried that the alumns enjoy in my class, but as I told u before sometimes they take too much confidence. Once I came to the class as every morning and everybody was talking. I gave them 5 minutes to be ready while I was taking note about the absents. I finished and they continued talking and talking. I said, ok, today we will study "Parelelism". They just stopped for two seconds to watch me, and then they continued talking. I started explaining the lesson anyway (I was on foot, writting and talking in the blackboard) but everybody continued talking and talking. As I saw that anyone was paying attention to my explanation, I said in low voice: "ok, I see you are not interested to hear me today so Bye Bye. See you tomorrow". And I started to take my stuffs and my bag. The classroom became suddenly in silence and everybody was like this Some alumns started to beg me pardom and to say Please, don't go professor, forgive us, don't go please. But I didn't say anything and in a very calm way I went from the class The next days never never never they started to talk again when i'm explaining:p
I have enjoyed a lot my throat has been the one who has suffered most

Hej, your explanation has been very helpful. Let's try a diagnosis:
The data would be this one: a woman, no pregnant, the whole blood analysis is ok except the level of prolactina that is very high. Some menstruations alterations (like two menstruations in a month). what would you do?


Postuar nga NS-6 datė 22 Mars 2006 - 14:53:

some info more

hahahahaha,i knew u were e good teacher...however remember the albanian methods i have told u...they have never failed in their whole history

ok,let's get back to the diagnosis:
did she measure the gonadotrophin releasing hormone(GnRH),follicle stimulating hormone(FSH) and the luteinising hormone(LH)?
prolactina is inhibitory for GnRH and so there will be a LH anomaly in concentration...this is seen in already 70% of the women with hyperprolactinoma.

also there is a dynamic test with TRH (thyreotropina) that shows whether it is an adenoma or a functional hyperprolactina (info based on the endocrinology manual of Andreoli)

MNR and CT are gold standart as it is used in medicine (the best,it means) to analyse any pituitary problem...

these are used in order to discover the primary causes of hyperproduction...there are some other causes that are rare but they need a more specialistic approach which i dont know by now...


Postuar nga amor alucius datė 22 Mars 2006 - 17:58:

Re: Re: prolactina and its hyperproduction

Citim:
Po citoj ato qė tha darke
. Once I came to the class as every morning and everybody was talking. I gave them 5 minutes to be ready while I was taking note about the absents. I finished and they continued talking and talking. I said, ok, today we will study "Parelelism". They just stopped for two seconds to watch me, and then they continued talking. I started explaining the lesson anyway (I was on foot, writting and talking in the blackboard) but everybody continued talking and talking. As I saw that anyone was paying attention to my explanation, I said in low voice: "ok, I see you are not interested to hear me today so Bye Bye. See you tomorrow". And I started to take my stuffs and my bag. The classroom became suddenly in silence and everybody was like this Some alumns started to beg me pardom and to say Please, don't go professor, forgive us, don't go please. But I didn't say anything and in a very calm way I went from the class The next days never never never they started to talk again when i'm explaining:p
I have enjoyed a lot my throat has been the one who has suffered most



NS-6,te lutem,mos e leviz kete postimin pa u lexuar nga marresi.Flm

Darke,can you bear some constructive critics?Please,accept my apologies if you think any of the following words is untrue.I'm not a teacher but I've a proff.home,I've asisted a lot of his lessons...and I'm a student myself(once I've been a pupil too),so I know more or less what must happen in order to have a successful lesson.


Where is your LEAD-IN?
Where is your PRESENTATION?
Are your pupils CENTRAL in this didactical method?
Is this INDUCTIVE learning?
And what about the TRANSLATION of the elements of some image you've brought with you to present your new topic?What about the next fase in your didactical method: INTERPRETATION?
ONLY when you've finished the above-mentioned steps you can say what your topic is about.
It's a very common mistake but it's a CAPITAL one,you saw the consequences.If I had been in their places,although I'm older and I can concetrate me longer than them,I would have acted the same.

A teacher NEVER opens his mouth to tell something about the lesson if they're not quiet,your first 2 minutes determinate ALL your lesson.
A teacher NEVER tells the topic immediately,but first brings something that connects with their world f.e. a picture with the elements you'are going to use later.Then you ask them to READ it,fi(f.e.-a building-a square object),then they interprate it(This is a building,miss).Then you write some of it's elements THENNNN you tell ur topic.
U can ask why is your lead-in that important?It's simple,if it's a good one,you get their ATTENTION immediately.
It's said that in teaching the importance of your content is 40%,the importance of your didactical method is 60%.


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