Monday, February 8, 2010
Biodegradable Scaffold Helps Incubate Stem Cells for Safer, Faster Growth
Filed under: Genetics
Growing stem cells efficiently and preventing contamination is a major stumbling block in developing them for therapeutic applications. Still these days, animal byproducts are used in Petri dishes that grow stem cells, leading to infection that may trigger an immune response once these cells are transplanted into the body. To overcome this issue, researchers at University of Washington in Seattle have developed a 3 dimensional structure to serve as a nesting site for stem cells to comfortably grow and propagate.
Zhang's [Miqin Zhang, UW professor of materials science and engineering] cylindrical scaffold is made of chitosan, found in the shells of crustaceans, and alginate, a gelatinous substance found in algae. Chitosan and alginate have a structure similar to the matrix that surrounds cells in the body, to which cells can attach. Different processing techniques can make the scaffold out of interconnected pores of almost any size, Zhang said.Researchers first seeded the scaffold with 500,000 embryonic stem cells, and after 21 days the scaffold was completely saturated. The cells infiltrated the structure, Zhang added, unlike other materials where cells often grow only on the surface.
To retrieve the cells, researchers immersed the scaffold in a mild solution. The structure is biodegradable and so dissolved to release the stem cells. One also could implant the stem cell-covered scaffold directly into the body.
Analysis of gene activity and testing in the lab and in mice showed that the new stem cells retained the same properties as their predecessors.
Other researcher groups are also looking for alternatives to feeder layers. The leading contenders are scaffolds coated with custom proteins designed to mimic the key properties of the animal cells in the feeder layer. Such products are expensive and difficult to produce in a consistent manner, Zhang said. The proteins also get used up in a few days and have to be replaced, making them costly and time-consuming for everyday use.
"Our scaffold is made of natural materials that are already FDA-approved for food and biomedical applications. Also, these materials are unlimited, and the cost is cheap," she said.
Press release: 3-D scaffold provides clean, biodegradable structure for stem cell growth ...
Abstract in Biomaterials: Feeder-free self-renewal of human embryonic stemnext term cells in 3D porous natural polymer scaffolds
Images: Top: The UW's biodegradable scaffold was built as a cylinder which was then cut into dime-sized slices. Bottom: A magnified view of the scaffold shows the pores, each about a tenth of a millimeter wide, where stem cells can grow.
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Medtronic's ENT Scope Sheath Proves Effective for Germicidal Protection
Filed under: ENT
A study out of Boston University School of Medicine, presented last week at the annual Triological Society meeting, has looked into the effectiveness of Medtronic's Slide-On Sensory Sheath as an alternative to germicidal immersion for flexible nasopharyngolaryngoscopes in between procedures. The condom-like device is wrapped over the fiber optic cable to prevent ENT scopes from getting dirty in the first place. The scope still requires an "enzymatic detergent cleaning and disinfection with 70 percent alcohol" when switching between patients, but the Slide-On should still save time during busy use of the scope.
From a Medtronic statement:
Microbial study results show that sterile disposable sheaths, when used with endoscopes, are as effective as using a liquid germicidal system for disinfecting scopes between patient procedures and provide protection against cross-contamination equivalent to immersion in germicidal solutions.The Medtronic Slide-On™ EndoSheath® System is a sterile, disposable cover for flexible endoscopes that provides a latex-free barrier between the scope and the patient. The system is designed to reduce patient contact with organic debris and staff exposure to hazardous chemicals. The study authors noted that the system is an alternative to time-intensive chemical reprocessing, allows for quick scope turnaround and helps physicians maximize time treating patients.
Press release: Study Suggests Slide-On Endosheath System Provides Several Advantages Over Traditional Germicidal Immersion ...
Product page: Slide-On™ Sensory Sheath ...
Flashbacks: Slide-On™ Sensory Sheath for ENT
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Jamie Heywood of PatientsLikeMe at TEDMED 2009
Filed under: in the news...
Jamie Heywood founded a website called PatientsLikeMe. Just like other social networks, PatientsLikeMe provides a place for people to discuss their condition, exchange information on countless diseases, etc. What makes PatientsLikeMe unique is the information that the firm mines from the content contributed by users. Here's Heywood giving a TEDMED talk about how his website can serve a similar function as large scale clinical trials and what useful data can be obtained from it.
Link: PatientsLikeMe...
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Dental Hearing Aid Technology from Sonitus Medical
Filed under: ENT
Sonitus Medical out of San Mateo, California is a company that's betting on bone conducting dental hearing implant technology. The SoundBite Hearing System that the firm is developing consists of a unit that has a microphone and wireless transmitter, and a tiny speaker that attaches to rear teeth to resonate and transmit the audio mechanically to the cochleae. The idea for this technology is not new and maybe risky, but Sonitus Medical seems confident it can earn regulatory approval and introduce an all new hearing aid technology to market.
The SoundBite hearing system consists of both a BTE (behind the ear) microphone unit, housing the receiver, wireless transmitter, and attached microphone, and a discreet, removable ITM (in the mouth) hearing device. An inductive charger unit is provided to charge the BTE microphone unit and ITM hearing device.SoundBite is designed to detect sound using a tiny microphone placed in an open-fit dome within the ear canal of the impaired ear. This nearly invisible microphone is attached by a thin tube to a transmitter unit called a BTE worn behind the ear. Placing the microphone in the ear canal is intended to allow the SoundBite hearing system to capitalize on the natural acoustic benefit provided by the patient's own pinna or outer ear to capture and direct sound.
Once sound is captured by the microphone, it is processed by the BTE digital audio device. The BTE wirelessly transmits sound to the removable ITM (in the mouth) hearing device, which is custom made for your own teeth for optimal comfort and function. The ITM hearing device in turn uses advanced technology to produce imperceptible sound vibrations that are conducted via the teeth, through bone, to the both cochleae. In this way, the SoundBite hearing system is intended to provide clear, high fidelity sound and thus restore normal hearing to patients who are essentially deaf in one ear with no surgery or modifications to the teeth required.
SoundBite hearing system is intended for patients who suffer from single sided deafness, conductive hearing loss, or mixed hearing loss and seek a non-surgical, non-invasive, hearing device that delivers high fidelity sound.
Product page: SoundBite ...
Related: In-mouth hearing aid co AudioDent closes down
(hat tip: ScienceRoll)
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The Cordis Manual FAIL for their RX Nitinol Stent System
Filed under: Vascular Surgery
, not funny
Take a break form your day to have a quick laugh at the expense of Cordis (a J&J company) and their accidental product manual that wasn't much of, well, a manual...
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Ins and Outs
Filed under:
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A Novel Resin to Treat Early Cavities
Filed under: Dentistry
DMG America, a dental technology company out of Englewood, N.J., is selling a light cured infiltrant resin that is useful for treating early cavities. At the very early stage of tooth decay, before a formal, treatable cavity has developed, fluoride treatment is often used as prophylaxis. But after a certain level of tooth decay, fluoride will be of no use, yet drilling the tooth to treat the cavity is not merited either, since filling a cavity with this method destroys healthy tooth tissue, and it is uncertain whether the decay will continue to a point that requires treatment. Dentists at this stage usually wait to see how the tooth decay progresses, but the Icon system gives dentists another option and allows them either the ability to treat decay that they view as particularly vulnerable to progression or treat a patient who they view as not likely to practice healthy dental hygiene. The technology is also useful for the treatment of cariogenic white spot lesions.
From the press release:
“Icon represents a new category of dental products,” said Tim Haberstumpf, DMG America director of marketing. “It is the first product to bridge the gap between prevention (fluoride therapy) and caries restoration. Icon’s micro-invasive infiltration technology can be used to treat smooth surface and proximal carious lesions up to the first third of dentin (D-1). In just one patient visit, Icon can arrest the progression of early enamel lesions and remove white spot lesions.”When a dentist discovers incipient caries that are beyond preventive therapies though too early for restorative treatment, Icon offers a simple alternative to the ‘wait and see’ approach. With Icon, the dentist can offer immediate treatment without unnecessary loss of healthy tooth structure. Icon prevents lesion progression and increases life expectancy for the tooth. Icon also provides a highly esthetic alternative to microabrasion and other restorative treatments for cariogenic white spot lesions. White spot lesions infiltrated by Icon take on the appearance of the surrounding healthy enamel.
Press Release: Introducing Icon...
Product Page: DMG Icon...
(hat tip: Gizmodo)
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David Agus Talks Cancer Research Strategy at TEDMED 2009
Filed under: in the news...
David Agus, professor of medicine at the University of Southern California and co-founder of personal genomics company Navigenics, spoke at last year's TEDMED about the state of available cancer therapy treatments and how far they've come from fifty years ago. Turns out the progress made so far has not been very promising and Agus is calling for a new strategy in attacking this multifaceted disease.
Link: TEDMED...
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A Message from Dr. Fiona Godlee, Editor-in-Chief of British Medical Journal
Filed under: not funny
Previously: A Message from Dr. Fiona Godlee, Editor-in-Chief of British Medical Journal; Global Warming Beliefs and The Hippocratic Oath: How BMJ Leadership Fails on Both; BMJ Urges Others, Fails to "Lead by Example" on Climate Change; Fionagate: An Illustrated, Interactive Website; Feet to the Fire: Responding to Dr. Godlee ; Carbon Footprint, or How to Spot Other People's Garbage
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