Articles
Discover Magazine: Is this the end of facial wrinkles and aging arteries that clog?
(By Shanti Menon, From the June 1999 Issue of DISCOVER Magazine, published online June 1, 1999)
The clusters of human skin cells basking in a sterile incubator, with alarms poised to go off if the level of carbon dioxide drops or the temperature wavers from 98.6 degrees, appear to be blessed with eternal youth. Under normal circumstances, skin cells divide about 50 to 70 times and then quickly wither and stop dividing. But after nearly two years in a laboratory at Geron, a Menlo Park, California, biotech company, these genetically altered cells are approaching 400 divisions and still show no signs of aging. They just keep multiplying.
Until now, endlessly multiplying cells indicated one thing: cancer. But Geron biochemist Cal Harley and cell biologist Jerry Shay, who has the same type of lab setup at the University of Texas Southwestern Medical Center in Dallas, say the remarkably youthful skin cells remain cancer-free. Moreover, Harley and Shay hope their success in prolonging the life span of these individual cells in the lab could eventually pave the way for more people to lead healthy and productive lives up to the age of 120. "One of the driving forces for trying to immortalize normal cells is that we may be able to treat or prevent the onset of certain diseases where cell aging plays a key role," says Harley.
He and Shay discovered their cellular fountain of youth when a strand of DNA they inserted into a skin cell prompted the production of telomerase, an enzyme naturally found in very young embryonic cells. Telomerase restores bits of DNA, called telomeres, which cap the ends of chromosomes and keep them from unraveling. Every time a cell divides, its telomeres get shorter, like the burning wick on a candle. When telomeres get down to a critical length, a cell will simply stop dividing. "Telomeres are now known to be the clock of cell aging," says Harley. "Telomerase is the enzyme that can rewind the clock. It gives us a way to restore an increased life span, a youthful life span, to aging cells."
Human Stem Cell News: Human Intestinal Stem Cell Breakthrough for Regenerative Medicine
ScienceDaily (Sep. 4, 2011) — Human colon stem cells have been identified and grown in a petri dish in the lab for the first time. This achievement, made by researchers of the Colorectal Cancer Lab at the Institute for Research in Biomedicine (IRB Barcelona) and published in Nature Medicine, is a crucial advance towards regenerative medicine.
Throughout life, stem cells of the colon regenerate the inner layer of our large intestine in a weekly basis. For decades scientists had evidences of the existence of these cells yet their identity remained elusive. Scientists led by the ICREA Professor and researcher at the Institute for Research in Biomedicine (IRB Barcelona) Eduard Batlle discovered the precise location of the stem cells in the human colon and worked out a method that allows their isolation and in vitro expansion, that is their propagation in lab-plates (petri dishes).
Growing cells outside the body generally requires providing the cells in a petri dish with the right mix of nutrients, growth factors and hormones. But in the same way that each of the more than 200 types of cells in our body differs from the others so too do optimal growing conditions for them in the lab. Consequently, human adult stem cell culture in labs has been practically impossible until now.
Batlle's team has also established the conditions for maintain living human colon stem cells (CoSCs) outside of the human body: "This is the first time that it has been possible to grow single CoSCs in lab-plates and to derive human intestinal stem cell lines in defined conditions in a lab setting," explains the IRB Barcelona researcher Peter Jung, first author of the study together with Toshiro Sato, from the University Medical Center Utrecht in The Netherlands.
The development, published by Batlle's research group in the journal Nature Medicine, arrives after more than 10 years of intense research focused on the characterization of the biology of the intestinal stem cells and its connection with cancer. The research has been made possible by close collaboration between Batlle's team and the group led by Hans Clevers at the Hubretcht Institute and University Medical Center Utrecht in The Netherlands, and María A. Blasco at the Spanish National Cancer Research Centre in Madrid (Spain).
"For years, scientists all over the world have been trying to grow intestinal tissue in lab-plates; testing different conditions; using different nutritive media. But because the vast majority of cells in this tissue are in a differentiated state in which they do not proliferate, they survived only for a few days," explains Jung. "The aim of this study was to find a way to identify and select individual CoSCs and to grow them while maintaining their undifferentiated and proliferative state in lab conditions. Thus, we would be able to model how they grow -- in number -- and differentiate into normal intestinal epithelial cells in lab-plates," continues Jung. The scientific community now has a defined 'recipe' for isolating CoSCs and deriving stable CoSCs lines, which have the capacity to grow undifferentiated for months. In fact, "now we can maintain stem cells in a plate up to 5 months or we can induce these cells to differentiate artificially, as they do inside our bodies."
"This achievement opens up an exciting new area of research with the potential to bring about a huge breakthrough in regenerative medicine," says Jung. Regenerative medicine -- or the idea of repairing the body by developing new tissues and organs as the old ones wear out -- involves growing new cells from patients into tissues and organs in a lab. However, the main element for making regenerative medicine a reality, namely adult stem cells, are just starting to be understood. "Now that guidelines for growing and maintaining colon stem cells in the lab are in place, we have an ideal platform that could help the scientific community to determine the molecular bases of gastrointestinal cell proliferation and differentiation. It is also suspected that alterations in the biology of CoSCs are at origin of several diseases affecting the gastrointestinal tract, such as colorectal cancer or Crohn's disease, an autoimmune and inflammatory disorder. Our discovery also paves the way to start exploring this exciting field," finishes Jung.
Altering Gene Sequences: Rapid Method of Assembling New Gene-Editing Tool Could Revolutionize Genetic Research
ScienceDaily (Apr. 9, 2012) — Development of a new way to make a powerful tool for altering gene sequences should greatly increase the ability of researchers to knock out or otherwise alter the expression of any gene they are studying. The new method allows investigators to quickly create a large number of TALENs (transcription activator-like effector nucleases), enzymes that target specific DNA sequences and have several advantages over zinc-finger nucleases (ZFNs), which have become a critical tool for investigating gene function and potential gene therapy applications.
"I believe that TALENs and the ability to make them in high throughput, which this new technology allows, could literally change the way much of biology is practiced by enabling rapid and simple targeted knockout of any gene of interest by any researcher," says J. Keith Joung, MD, PhD, associate chief for Research in the Massachusetts General Hospital (MGH) Department of Pathology and co-senior author of the report that will appear in Nature Biotechnology and has received advance online release.
TALENs take advantage of TAL effectors, proteins naturally secreted by a plant bacteria that are able to recognize specific base pairs of DNA. A string of the appropriate TAL effectors can be designed to recognize and bind to any desired DNA sequence. TALENs are created by attaching a nuclease, an enzyme that snips through both DNA strands at the desired location, allowing the introduction of new genetic material. TALENs are able to target longer gene sequences than is possible with ZFNs and are significantly easier to construct. But until now there has been no inexpensive, publicly available method of rapidly generating a large number of TALENs.
The method developed by Joung and his colleagues -- called the FLASH (fast ligation-based automatable solid-phase high-throughput) system -- assembles DNA fragments encoding a TALEN on a magnetic bead held in place by an external magnet, allowing automated construction by a liquid-handling robot of DNA that encodes as many as 96 TALENs in a single day at a cost of around $75 per TALEN. Joung's team also developed a manual version of FLASH that would allow labs without access to robotic equipment to construct up to 24 TALEN sequences a day. In their test of the system in human cells, the investigators found that FLASH-assembled TALENs were able to successfully induce breaks in 84 of 96 targeted genes known to be involved in cancer or in epigenetic regulation.
"Finding that 85 to 90 percent of FLASH-assembled TALENs have very high genome-editing activity in human cells means that we can essentially target any DNA sequence of interest, a capability that greatly exceeds what has been possible with other nucleases," says Jeffry D. Sander, PhD, co-senior author of the FLASH report and a fellow in Joung's laboratory. "The ability to make a TALEN for any DNA sequence with a high probability of success changes the way we think about gene-altering technology because now the question isn't whether you can target your gene of interest but rather which genes do you want to target and alter."
The research team also found that the longer a TALEN was, the less likely it was to have toxic effects on a cell, which they suspect may indicate that shorter TALENs have a greater probability of binding to and altering unintended gene sites. Joung notes that this supports the importance of designing longer TALENs for future research and potential therapeutic applications.
In 2008, Joung and colleagues at other institutions established the Zinc Finger Consortium, which has made a method of engineering ZFNs broadly available to academic laboratories. His team is now making the information and materials required to create TALENs with FLASH available within the academic community, and information about accessing those tools is available at http://TALengineering.org. Gene editing nucleases, including both ZFNs and TALENs, were recently named "Method of the Year" for 2011 by the journal Nature Methods.
Joung says, "While I believe that TALENs ease of design and better targeting range will probably make them a preferred option over ZFNs made by publicly available methods, ZFNs' smaller size and the less repetitive nature of their amino acid sequences may give them advantages for certain applications. For the time being, it will be important to continue developing both technologies." Joung is an associate professor of Pathology and Sander an instructor in Pathology at Harvard Medical School,
The study was supported by grants from the National Institutes of Health -- including an NIH Director's Pioneer Award to Joung -- and by the Jim and Ann Orr MGH Research Scholar award. Co-lead authors of the Nature Biotechnology paper are Deepak Reyon, PhD, and Shengdar Tsai, PhD, of MGH Molecular Pathology Unit and the Center for Computational and Integrative Biology (CCIB). Additional co-authors are Cyd Khayter and Jennifer Foden, both of MGH Molecular Pathology and the CCIB.
Reducing Kidney Stones at Home
If you have kidney stone symptoms & causes, try the home remedies for kidney and other stones given on this page, irrespective of the cause of kidney stone.
For patients with recurring kidney stones, a study found that a bug - a bacterium, O formigenes can cut down up to 70 per cent of the risk associated with stones with no known side-effects. The findings of the study have been published by researcher David Kaufman in the online issue of the Journal of the American Society of Nephrology in March 2008.
Magnesium rich foods such as apples, aprocots, avocado, beans, walnuts , etc. help prevent the formation of kidney stones.
Lemons have the highest concentration of citrate of any citrus fruit. Citrate is a natural inhibitor of kidney stone formation.
Drinking four ounces (120ml) of reconstituted lemon juice in two litres of water per day decreases the rate of stone formation, according to Roger Sur, director of UC San Diego Comprehensive Kidney Stone Center (June 2010).
You may try the following home remedies for kidney stones. Read the other options available for the treatment of kidney stones.
Drink more water or fluids throughout the day to produce at least 2 litres of urine in the whole day. Note that It is the amount of urine that is important, at least 2 litres of urine in the whole day.
Remedy using lemon juice & olive oil
Drink a mixture of 2 oz (60 ml) of lemon juice with 2 oz (60 ml) of olive oil and then a large glass of water. The stones should pass within 24 hours to give you relief. This remedy for kidney stones has worked for many.
Remedy using coconut water:
Drinking coconut water (naariyal paani) regularly can break up the stones and make them easier to pass out.
Remedy using orange juice:
Studies reported in 2006 by researchers at UT Southwestern Medical Center have discovered that a daily glass of orange juice can help prevent the recurrence of kidney stones better than other citrus fruit juices such as lemonade. A glass of orange juice a day may keep kidney stones at bay.
Remedy using onions:
Take 2 medium size onions in 1 glass of water and cook over medium heat. When it cools down, blend in a blender. Strain and drink the juice for 3 days. You will start passing the stones from the second day. This remedy has worked for many.
Remedy using pomegranates:
Take 1 cup of pomegranates seeds and 2 cups of horse gram (Kulthi) and make of soup. Drink this soup for kidney stone removal.
Kidney Stones remedy using kidney beans:
Remove the beans from the kidney beans pods. Boil 50 gram of these pods (chopped) in four litre of water for six hours. Strain the liquid should through a muslin and cool the liquid for about 6 hours. Drink a glass of this decoction every two hours throughout the day for the first day and, then, several times a week.
Herbal remedies for kidney stones:
Chinese have been using the herb, "Chicken Bone Grass" for the treatment or removal of kidney stones and gallstones.
Mix 3 oz pineapple juice, 3 oz tonic water, a pinch of nutmeg and a pinch of cinnamon and drink in the morning and night for 4-5 days.
Other helpful foods
Drink plenty of water and other fluids, up to 3 litres daily. Avoid foods like alcoholic and carbonated beverages; condiments and pickles; certain vegetables like asparagus, beans, cabbage, cauliflower, cucumber, radish, spinach, tomato, onion, rhubarb and meat.
Follow a low protein diet. Excessive protein can increase uric acid, calcium and phosphorus in the urine.
Reduce calcium and phosphates in supplement form. They can be taken from dietary sources.
Do not take vitamin C supplements.
A diet low in protein, nitrogen and sodium intake.
Remain physically active. Physical activity does not allow the calcium to accumulate in the kidneys.
Eat foods high in vitamin A such as apricots, broccoli, cantaloupes, carrots, pumpkins, sweet potatoes, etc.
Vitamin B6 or pyridoxine has been shown to be useful in the treatment of kidney stones. A daily does of 100 to 150 mg of vitamin B6 or pyridoxine may be taken for months for permanent cure of kidney stones. Consult your Doctor before starting any supplements.
