Author: Ghatalia Pooja
Institution: Molecular Biology
Date: January 2008
This article is a combined effort of JYI's
Science Journalists (names listed below the article), Features Editors (Emma Wear, HoiSee Tsao, David Metcalfe, Ben-Griffin Smith) and the Senior Features Editor Pooja Ghatalia.
Scientific comforts A Breakthrough in Wireless Electricity
The days of using overloaded and possibly hazardous electrical sockets for the purposes of powering and recharging appliances and gadgets might soon be a thing of the past. In the July 6th edition of the journal Science, researchers at MIT announced the success of an efficient power transfer between two coils over a large distance relative to their size. Presently, things such as security swipe cards can transmit electricity via magnetic induction but can only do so over a small distance. However, this demonstration, which used the Wi-Fi concept to transmit power, raises the hope of eliminating the necessity of wires in the transmission of electricity in the future, and suggests the possibility of beaming power to any electrical devices within a given range.
The MIT experiment utilized two precisely tuned, "self-resonant" coils to boost efficiency of the power transfer. Power was loaded onto one coil, a few feet in diameter, causing electricity to oscillate back and forth more than a million times a second within the coil. This electrical current caused a flickering magnetic field to be transmitted from one coil to the other. The second coil resonated with this magnetic field, which, in turn, induced an electrical current within the coil. These electrical surges could then potentially be used to power or recharge appliances.
Said lead author André Kurs about the potential applications of this wireless power transfer, "We think this can be useful over distances of a few meters. It could supply power to just about any household object that needs electricity." - By Matt Getz.
A Rubber with a memory and its power to change science
There is one promising advancement regarding a new invention in the field of Chemical Engineering that must be covered. Mitchell Anthamatten, inventor of a new breakthrough rubber material which could affect many fields,most notably medicine at the time,explains how this new type of rubber could be used: "The pressure at which you hold together a sutured wound determines a lot about how it will heal. This polymer could be made into a thread that responds precisely to body temperature."
The possibilities, as one may imagine, for this type of invention are endless. Anthamatten even explains how the rubber could be applied combined with the utilization of a dye, to the commercial market for quite a beneficial use, "We expect the rate of dye diffusion to increase with temperatures." Imagine a world in where you buy a gallon of milk, or something of the sort, and you need not bother thinking about its potential for going bad; there would be a label that involves the use of dyes in Anthamattens' rubber, and instead of a untrustworthy date you would see the label color turn red when the product no longer was in ripe condition. Anthmatten remarks, "People want to know when their products are fresh." - Bt Jeffrey Kost
Sunlight into electrical energy
In May 2007, scientists from Rice University reported a new way of making four-legged cadmium selenide quantum dots, with cheaper, safer compounds and better results. Four-legged quantum dots, also known as tetrapods, are effective at converting sunlight into electrical energy. While the production of cadmium selenide used to be difficult, scientists are now able to use a compound found in some shampoos to synthesize cadium selenide with cheaper raw materials and fewer purification steps.
Former methods produced tetrapods with arms that were uneven in length, crooked, or even missing. To further complicate matters, even the best trials yielded particles that were not tetrapods thirty percent of the time.1 With this new method, scientists can have greater control of the tetrapods' shape and a higher yield. - By Shilpa Gowda
Disease Diagnosis and Prevention Test for early stage lung cancer
The leading killer cancer, lung cancer, has remained deadly because of its late diagnosis rather than lack of effective treatment. But with the new screening test, LC Detect, discovered this year, we can definitely breathe a sigh of relief. The works by measuring the serum levels of Human Aspartyl (Asparaginyl) β-Hydroxylase (HAAH).
Lung cancer patients have three times higher concentration of HAAH than the normal people. Besides, it is present since early stages of lung cancer. So, scientists saw its potentiality as a good screening test and have recommended it for men and women, 50 years of age or older, who have smoked cigarettes extensively in the past, regardless of their current smoking habit.
Of course, this test alone can't confirm a diagnosis of lung cancer. However, it can be used in conjunction with other tests like chest x-rays, CT scans etc. 0 By Suvash Shrestha.
Male circumcision: a protection against HIV
In 2007, male circumcision made big news as two large randomized trials published in The Lancet showed this simple procedure halved the risk of HIV infection in men.
The authors proposed an attractive mechanism for protection offered by circumcision. The foreskin is rich in HIV target cells, and during intercourse the foreskin is retracted which exposes its inner mucosa unkeratinised and thus more vulnerable to vaginal and cervical fluids. Thus uncircumcised men are more easily infected with HIV.
These both studies complement the findings of a previous South African study and together they provide a solid evidence base for implementing male circumcision as a preventive measure against HIV/AIDS. Although male circumcision has been hyped as a new era in the prevention of HIV/AIDS, the fact that circumcision does not provide 100% protection should not be overlooked and its role should be to support and not replace other preventive measures like condoms.
- By Suvash Shrestha.
Molecular assay for intra operative assessment of breast cancer metastasis
Scientists have developed a new and promising molecular assay that will help the surgeons to accurately assess the metastatic status of lymph nodes during breast surgeries.
During the breast cancer surgeries, surgeons examine the lymph node closest to the breast the sentinel node (SLN) for the signs of metastasis with frozen section and touch preparation. If SLN metastasis is present, they take out the additional lymph nodes as well in the same setting. However, when compared with final permanent pathology results which take a day or two, the intra operative histologic techniques have limited sensitivity. So, it often happens that owing to the false negative results, the patient has to return for repeat surgery which means additional cost and additional anesthetic and operative morbidity.
But now, scientists seem to have found a cure to this problem the GeneSearch BLN assay, an intra operative reverse transcriptase polymerase chain reaction assay for SLN metastasis. In a study published in The American Journal of Surgery, 2007, Pat W. Whitworth and his colleagues compared the BLN assay results with conventional histologic evaluation techniques. Thus scientists believe the BLN assay is properly calibrated for use as a stand alone intra operative molecular test which the surgeons can totally rely upon and which can help to detect even early stage metastases. - By Shilpa Gowda.
Genomics and Stem cells
Use of embryonic stem cells in research promise tremendous therapeutic benefits, but the procedure to obtain these stem cells has been controversial. To bring an end to the controversy, scientists have developed new methods to obtain stem cells. Researchers this year have leaped from obtaining the entire genome sequence of a single individual to creation of a synthetic genome.
Bacterial Genome Transplantation
The field of synthetic genomics was bolstered in June when biologists at the J. Craig Venter Institute announced that they had successfully transplanted the genome of one bacterium into another bacterial species. This genome transplantation represents a large advancement in the field, as it facilitates the development of new microorganisms via genetic transfer. "This was the ultimate in identity theft," Venter says. "The chromosome [genome] that we put in took over the cell completely, and any characteristics of the original species were lost." The genome transfer was carried out by polyethylene glycol-mediated transfer, which facilitates the transfer of large circular pieces of DNA, such as the genome of a bacterium.
Several procedures were performed after the transformation to make sure that it had taken place. Two genes were added to the donor species' chromosome, one that made the cells resistant to the antibiotic tetracycline and the other that made the colonies turn blue in the presence of the compound X-gal. The group then grew the transformed cells on a media containing tetracycline and X-gal and looked for the cells that grew up and turned blue, which indicated that the cells had taken up the donor DNA. They then screened these blue, tetracycline resistant cells for traces of the host genome and found none. They finally discovered that all of the proteins made by the new, host bacterium were characteristic of the donor bacterium.
This discovery represents a watershed in Venter's decade long quest to create a fully synthetic life-form. He says it now could be just months before a living cell with a synthetic genome is a possibility.
- By Matt Getz.
Mapping the genome
This year, scientists have obtained the entire genome sequence of one individual. Though scientists obtained two versions of the genome in 2001, these genomes involved a mosaic of DNA from different individuals; one of them, 5 individuals, and the other, over 100. The findings from the new study are significant also because parental chromosomes of the newly sequenced DNA showed more differences than expected, which suggests that there may be more diversity between individuals than previously thought.
While earlier genome sequencing projects estimated the variation to be around 0.1 percent, current estimates are now around 0.5 percent1. Dr. Craig Venter, whose genome was sequenced, is also the president of the organization that obtained the sequence, the J. Craig Venter Institute in Rockville, MD. He reports, "With this publication we have shown that human to human variation is five to seven-fold greater than earlier estimates proving that we are in fact more unique at the individual genetic level than we thought ."
Scientists hope to one day enable physicians to determine what diseases patients are susceptible to just by looking at their DNA. They hope to make genome sequencing an affordable procedure, on the order of a thousand dollars or less. - By Shilpa Gowda.
Breakthrough in Obtaining Stem Cells May Eliminate Embryo-Related Controversies
Scientists from Madison, Wisconsin have reported in Science magazine that they are now able to turn adult skin cells into stem cells. The potential for stem cells as a cure for chronic diseases like heart disease, diabetes, or multipe sclerosis (MS) has always been recognized, yet ethical concerns about obtaining stem cells from human embryos have slowed down stem cell research. Fortunately, the new method for obtaining stem cells bypasses the need for human embryos, and Dr. Douglas A. Melton, co-director of the Stem Cell Institute at Harvard University goes so far as to say that it is "ethically uncomplicated."
The scientists state that they are able to turn the adult skin cells into cells that exhibit the essential characteristics of embryonic stem cells, by adding only four genes. These four inserted genes produce factors, which are reprogramming the cell and which are present in fertilized oocytes, so a method called nuclear transfer works. These stem cells would not be able to result in a whole embryo, because they could not give rise to a placenta, but would be able to grow any tissue in the adult human body. - By Shilpa Gowda.
top left - progression of cancer, NIH top right - Craig Venter bottom left - Solar cell bottom right - production of stem cells
Curing the disease Making holes in evil cells .
In a collaborative effort, two engineers and a team of skilled scientists have discovered a way to specifically target and destroy cancer cells using electric pulses. These engineers, Rafael V. Davalos, of the Virginia TechWake Forest University School of Biomedical Engineering and Science, and Boris Rubinsky, of University of California, Berkeley invented irreversible electroporation (IRE), a technique by which cancerous cells can be specifically targeted and destroyed..
With electroporation, a cell can go from being impermeable to being reversibly permeable to being irreversibly permeable (IRE), during which the cell will die. It is this concept that Davalos and Rubinsky used to target and kill cancer cells in a rat model.
"IRE removes tumors by irreversibly opening tumor cells through a series of short intense electric pulses from small electrodes placed in or around the body," said Davalos. "This application creates permanent openings in the pores in the cells of the undesirable tissue. The openings eventually lead to the death of the cells without the use of potentially harmful chemotherapeutic drugs." - By Falishia Sloan.
Telomere Research Provides New Perspective for Treating Cancer
A human metaphase (middle step in chromosome replication) stained for telomeric repeats. DAPI stained chromosomes are false-colored in red, telomeres are in green, by Claus Azzalin, ISREC.
Researchers at the Swiss Institute for Experimental Cancer Research (ISREC) and at the University of Pavia have found that RNA is present in the components of chromosomes called telomeres. This discovery about telomeres, whose DNA has long been thought not to transcribe into RNA as the rest of the DNA present on a chromosome does, could provide scientists with a novel way of halting the telomere replenishment, and therefore the lifespan, of cancer cells.
After a certain number of replications, the telomeres of a chromosome, located at the ends, activate a sort of stop signal to prevent further replication. The dysfunction of the telomeres in providing this stop signal can lead to continuously dividing or damaged chromosomes, in turn leading to cancer or other diseases.
It has been found that in about 90% of human cancers, telomere maintenance occurs, where telomerase continues to regenerate the telomeres long after they, and the cancer cells they are in, should have died. This continuing regeneration of the telomeres leads to a continuing maintenance and lifespan of cancer cells.
- By Falishia Sloan.