Death from Cancer Cases Continue to Decline in US

The mortality rates and new cancer cases have decreased dramatically in the past years. The diagnosis rate of cancer has been decreasing by about 1 percent every year from 1999 to 2006. Mortality rates decreased an average of 1.5 to 2 percent between men and women between 2001 and 2006.

These declines are attributed to the drop in death rates from the more common cancers such as lung, prostate and colorectal in men and breast and colorectal in women. Breast cancer rates have been dropping at an average of 1.2 percent per year from 1997 to 2006. Though some cancer types have been decreasing, some have actually been increasing. For men, kidney and liver cancer rates have been increasing while prostate, lung, and bronchus oral cavity cancers have been decreasing. Similarly for women, lung, thyroid, pancreas, and urinary bladder cancers have been increasing. Also reported in both genders, leukemia and melanoma rates have been increasing.

These findings are reported by researchers from the National Cancer Institute, Centers for Disease Control and Prevention, American Cancer Society, and the North American Association of Central Cancer Registries.

http://www.cnn.com/2009/HEALTH/12/07/cancer.deaths.down/index.html

Stem Cells can Repair Damage

According to a phase one study at the US National Heart, Lung, and Blood Institute, 53 patients have showed improved post-heart attack cardiovascular muscle repair with the injection of adult stem cells. It was found that patients with stem cells from donor bone marrow have promoted the growth of new blood vessels in the cardio tissue damaged by a heart attack.

The patients in the study received stem cell injections 10 days after receiving a heart attack. They were compared to patients who had received placebo injections. After about 6 months, those who got stem cells were 4 times better off, pumped more blood per heart beat, and had about ¼ the amount of irregular heartbeats than the patients who had received placebo injections.

According to a report published in the Journal of the American College of Cardiology there were no s serious side effects with the stem cell treatment.
Before this trial it was believed that only embryonic stem cells could turn into heart or other organ cells.

http://health.yahoo.com/news/healthday/adultstemcellscanrepairdamagedheart.html

Kelli Martinez
VTPP 434-502

Biodegradable Stents for Coronary Artery Disease treatment

Regular metal stents though successful in their purpose to treat coronary artery disease, present limitations such as stent thrombosis and restenosis. Drug-eluting stents are a step forward in the development of stents, since they significantly reduce restenosis rates and the need for repeat revascularization. However, they are still associated with subacute and late thrombosis, and necessitate prolonged antiplatelet therapy for at least 12 months. Further, the polymer used as a vehicle for drug delivery may induce vessel irritation, endothelial dysfunction, vessel hypersensitivity and chronic inflammation at the stent site.

As there is a pressing need for a stent that would cause less complications and that could be “removed” from the vessel after it is no longer needed, the biodegradable stent is a potential possibility to solve this issue. After completing their purpose, biodegradable stents are bioabsorbed leaving only the healed natural vessel behind. This decreases enormously (if not completely) the chance for late stent thrombosis since the stent is gone, and prolonged antiplatelet therapy is not necessary in this instance. Bioabsorbable stents can also be suitable for complex anatomy where stents impede on vessel geometry and morphology and are prone to crushing and fractures.

Also, these biodegradable stents can be use for drug and/or gene delivery such as transferring genes that code key regulatory pathways of cell proliferation inside the cells of the arterial wall. Regardless of which agent (drug or gene) will finally conquer restenosis, a polymer stent remains an optional vehicle for such delivery. What’s more, bioabsorbable stents are compatible with MRI and MSCT imaging.

Besides polymer biodegradable stents, also in consideration are metal bioabsorbable stents since they have the potential to perform similarly to stainless steel metal stents. So far, two bioabsorbable metal alloys have been proposed for this application: iron and magnesium. The biocompatibility of these stents depends on their solubility and their released degradation products. Their local toxicity is related to the local concentration of the elements over time. The tissue tolerance for physiologically occurring metals depends on the change of their tissue concentrations induced by corrosion. Thus metals with high tissue concentrations are the ideal candidates for bioabsorption stents.

This is a very interesting issue since biodegradable stents not only would facilitate the life of the patients after the stent is no longer needed by eliminating the chance of late stent thrombosis and thus the need for prolonged antiplatelate therapy but they would also be useful for other applications such as angiogenesis and gene transfer. Once they deposit the drug locally, the vehicle as a whole will disappear in the surrounding tissue. It would be an excellent medical progress if the biodegradable stents could replace the current practice in which many patients chronically carry metal prostheses in their coronary arteries.

The article can be found in http://www.invasivecardiology.com/article/5222

Geraldine Pena-Galea

Vibrating Technology Promises to Replace Biopsies in Diagnosing Diseased Tissue

Scientists at the Mayo Clinic have developed a new way to "see" into the body by using vibrations, it is called magnetic resonance elastography (MRE). It sends vibrations into the body that can be picked up by a modified MRI machine. The tissues in the body move only microns due to these vibrations, but by applying advanced mathematical models to the data doctors and scientists can make an image of the body. It was inspired by the fact that doctors can diagnose a lot of things just by feeling the patients body that advanced imaging techniques cannot pick up. The doctors are feeling the relative densities in the body when they do this, and the MRE does the same thing with the vibrations. This should make diagnosing certain things much easier, like detecting liver disease.

I found this article very interesting because medical imaging is directly related to Biomedical Engineering, and because advancements like these can vastly improve a patient's life and can make the doctor's job much easier.

http://www.scientificamerican.com/article.cfm?id=magnetic-resonance-elastography

Scott Eagleston
VTPP 434-502

Drug-Dispensing Contact Lens Could Replace Imprecise Eye Drops

August 12, 2009
Researchers investigate new biodegradable polymer lens materials that could ensure the proper delivery of medicine for treating glaucoma, chronic dry eye, corneal ulcers and other ocular ailments
By Jim Nash

Eye drops often provide quick relief to those suffering from minor eye problems such as redness, itching and dryness, but doctors have found that such dollops of medicine do not work very well for more serious conditions such as glaucoma, chronic dry-eye and corneal ulcers. Help may be on the way for those suffering from these or other ocular ailments in the form of a contact lens that sandwiches medicine between two layers of polymer film and administers large doses of medication at constant rates over extended periods.In lab tests, prototype multilayer lenses have shown they can release ciprofloxacin (an antibiotic often used to treat eye and other infections) for up to 100 days, according to a study published in the July issue of Investigative Ophthalmology and Visual Science by researchers from Children's Hospital Boston, the Massachusetts Eye and Ear Infirmary's (MEEI) ophthalmology department, Schepens Eye Research Institute in Boston, and the Massachusetts Institute of Technology's (M.I.T.) chemical engineering department.One of the most important roles these contact lenses could play, according to the researchers, is simply getting all of a given medical dose into a patient's eyes. It is not uncommon for as little as 1 percent of eye-drop solution to get into and stay on the eye long enough to be absorbed, they add.The breakthrough is the suspension of medicine in a layer made from PLGA (poly(lactic-co-glycolic acid)), a biodegradable polymer. PLGA regulates the amount of drugs medication that passes through it at any given time. The more PLGA there is in relation to the medication, the slower the drug it is released, says pediatric critical care specialist Daniel Kohane, director of the Laboratory for Biomaterials and Drug Delivery at Children's Hospital and the project's lead researcher.The researchers coated the PLGA film with another polymer, poly-HEMA (poly(2-hydroxyethyl methacrylate)), to form the lens. Poly-HEMA is a transparent hydrogel that allows the patient to see as drugs from the degrading PLGA layer leak through it onto the eye's surface. Medicine-dispensing contacts should also serve as an efficient method of preventing potentially dangerous post-op infections, Kohane says.Kohane and his colleagues, whose work is funded to the tune of about $250,000 annually from the National Institute of General Medical Sciences, are one of several teams investigating the use of layered drug-dispensing soft contact lenses. Researchers at Spain's University of Santiago de Compostela in the March issue of Biomaterials reported on their work developing acrylic hydrogels with an improved ability to carry drugs and maintain controlled release rate. Singapore's Institute of Bioengineering and Nanotechnology in 2004 announced it had developed a permeable polymer lens that could be laden with eye medication for ocular drug delivery. Two of its researchers were granted joint patents for "Drug-Loaded Contact Lenses for Ocular Drug Delivery" in Taiwan (2007) and Singapore (2008).The concept of a disposable drug-doling contact lens has been kicked around at least since the 1960s, but attempts have ended with lenses unable to regulate drug diffusion well enough, says Joseph Ciolino, an ophthalmologist with the MEEI and another of the project's researchers. Although it is too early to determine how much such lenses might cost, given that they are only now being moved into animal testing, Ciolino says that he and Kohane think animal testing can be completed in a year. "I look at these lenses and think about people with corneal ulcers, and who have to put drops in every half hour, sometimes for months," he says. "That's a cruel punishment." As many as half of glaucoma sufferers do not follow doctors' orders because of the difficulty administering drops, he adds.One of the key questions that the researchers will have to answer during testing is how well these special lenses will fit on patients' eyes, which vary in shape and size, says Mitchell Cassel, an optometrist and owner of Studio Optix in New York City who says he is familiar with the work being done by Kohane, Ciolino and their colleagues. "Some people have acute sensitivity in the insides of their eyelids, too," Cassel adds.
http://www.scientificamerican.com/article.cfm?id=drug-dispensing-contact-lens&SID=mail&sc=emailfriend

I think this a very important path for ophthalmology to go down as it would help with many eye problems. I would have to say this would be a more efficient way of dispensing the medicine to the eye because someone like me has always had problems with eye drops and once the drops hit your eye you reaction is to squint and that just forces all the medicine out. Glaucoma patients would probably benefit from both the new intent of contact lens but, also the old since most of these patients end up having to wear glasses for general vision correction. This new form of medicine dispensing would also help patients to remember to use their medicine when they are directed to do so because they could essentially put the lenses in and forget about having to remember anything else about the medicine.

No-Entry zone for AIDS virus

AIDS virus integrates its genetic material into the genome of the infected cell. Recent research has found specific sites in the human genome that are not affected by this integration process. This information can be used in the development of gene delivery vehicles in gene therapy. About 46,000 known integration sites of HIV-based gene delivery vehicles have been analyzed. These sites were determined in various gene therapy studies and are available in gene databases.

Before, researches used to think that HIV and HIV delivery vehicles have a preference to the sites where the gene transcription starts. Although many HIV vehicles do integrate close to these start points, the database analysis shows that very few of these integration sites were close the transcription start points. This is important information because it gives scientists a detailed map of where in the genome that the HIV does not integrate.

It is believed that the sites in the genome untouched by HIV integration lack a certain factor that is needed for the virus. It is also possible that some mechanism is working at these sites to block the HIV from integrating. We know that the blocking factor is unspecific because other retroviruses prefer to insert their material directly on these start sites.

Scientists agree that the best way to treat viral immune deficiency is to prevent the virus from integrating into the DNA. By studying this mechanism that blocks the HIV from integrating at the transcription start sites, researchers hope to one day be able to mimic and manipulate this mechanism so it can be applied to other unprotected sites in the genome.

Michael McCarroll
VTPP 434-502

Implantable Cancer Vaccine

A device to prevent cancer has been developed and can actually be implanted into the body, anywhere under the skin of the patient. These polymer disks have an 8.5 mm diameter and are packed with “tumor specific antigens.” These disks are able to “reprogram” the immune system into attacking cancerous tumor cells. The device does this by releasing cytokines, which then recruit dendritic cells (immune-system messengers). These dendritic cells then go into the implant and become exposed to the tumor specific antigens discussed previously. After exposure, the dendritic cells “report” to the lymph nodes, where they tell the T cells of the immune system to seek and destroy the tumor cells. This fingernail-size device has eliminated melanoma tumors in mice a recent study has shown.

This is a fascinating new development in the field of cancer treatment. I am particularly interested in this topic because my aunt had a cancerous tumor diagnosed and treated some years ago. This treatment is much less invasive than they chemotherapy/ surgery alternative, and does not damage healthy cells at all as it only targets tumor cells.

http://news.yahoo.com/s/hsn/20091125/hl_hsn/implantablecancervaccineshowspromise

Charlcie Northrop
VTPP 434-502

Laparoendoscopic Single-Site Surgery: Initial Hundred Patients

UroToday.com - This is the first report of a large number of patients who underwent laparoendoscopic single site surgery (LESS). The work was done at three sites (Cleveland, Ohio; Caracas, Venezuela; and Gujarat, India).

Overall, 15% of all of the laparoscopic procedures at these institutions were performed using LESS between October 2007 and December 2008. These procedures included renal ablative (nephrectomy - simple, donor, and radical; partial nephrectomy; nephroureterectomy), renal reconstructive (pyeloplasty), and transvesical simple prostatectomy. Procedures were done using the r-Port in combination with bent/articulating as well as standard laparoscopic instruments. Additional ports were needed in 6% and there was a 4% conversion rate. Extensive data were collected including hospital stay, complications, analgesic use, return to work and complete convalescence. At this time, the data for LESS are quite similar to the data for standard laparoscopy. No analysis of cost was done in this report; however, the r-PORT and the disposable articulating instruments are additional expenses that need to be considered. Other surgeons using LESS have been able to decrease the cost by using standard periumbilical trocars (e.g. Dr. Cadeddu at UT Southwestern) and nondisposable bent instruments. The authors sagely and cautiously note in their conclusion: "The LESS urologic surgery is feasible for select indications, albeit technically challenging. Outcomes in the short term appear comparable to conventional laparoscopy as reported in published data. Prospective studies comparing outcomes of LESS surgery with standard laparoscopy will determine the future direction of this approach."

The age old saw of "it's new, but is it better?" needs to be applied, especially when "new" means more difficult for the surgeon to master and more expensive. As with the slow adaptation of laparoscopy versus open surgery, the urological community needs to know if LESS vs. standard laparoscopy will provide equal efficacy as well as equal or better efficiency at less cost and with improved patient well-being (i.e. less analgesic use, shorter hospital stay, quicker convalescence and better cosmesis).

At this early stage in its development, prospective randomized studies can be done by those skilled in the technique; I would encourage these pioneers to seek Level I answers.

http://www.medicalnewstoday.com/articles/172486.php

This article describes a new way to perform laproscopic procedures. The new method is called LESS and is even less invasive than standard laproscopic procedures for the patient. The hope is that it will become more mainstream and also has the potential to become less expensive than standard laproscopic procedures. I was interested in this article because I have witnessed a laproscopic nephroectomy and observed that even with removing the entire kidney the patient was in the hospital for a a relatively short amount of time. It is amazing how biomedical engineers can make something that is even less invasive that will be cheaper in the long run.