Seeing the world differently



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'Grow your own transplant' may be possible for men with type 1 diabetes

Researchers turn human testes cells into insulin-producing islet cells; diabetic mice were 'cured' for a week

PHILADELPHIA – Men with type 1 diabetes may be able to grow their own insulin-producing cells from their testicular tissue, say Georgetown University Medical Center (GUMC) researchers who presented their findings today at the American Society of Cell Biology 50th annual meeting in Philadelphia.

Their laboratory and animal study is a proof of principle that human spermatogonial stem cells (SSCs) extracted from testicular tissue can morph into insulin-secreting beta islet cells normally found in the pancreas. And the researchers say they accomplished this feat without use of any of the extra genes now employed in most labs to turn adult stem cells into a tissue of choice.

"No stem cells, adult or embryonic, have been induced to secrete enough insulin yet to cure diabetes in humans, but we know SSCs have the potential to do what we want them to do, and we know how to improve their yield," says the study's lead investigator, G. Ian Gallicano, Ph.D., an associate professor in the Department of Cell Biology and Director of the Transgenic Core Facility at GUMC.

Given continuing progress, Gallicano says his strategy could provide a unique solution to treatment of individuals with type 1 diabetes (juvenile onset diabetes). Several novel therapies have been tried for these patients, but each has drawbacks. Transplanting islet cells from deceased donors can result in rejection, plus few such donations are available. Researchers have also cured diabetes in mice using induced pluripotent stem (IPS) cells – adult stem cells that have been reprogrammed with other genes to behave like embryonic stem cells – but this technique can produce teratomas, or tumors, in transfected tissue, as well as problems stemming from the external genes used to create IPS cells, Gallicano says.

Instead of using IPS cells, the researchers turned to a readily available source of stem cells, the SSCs that are the early precursors to sperm cells. They retrieved these cells from deceased human organ donors.

Because SSCs already have the genes necessary to become embryonic stem cells, it is not necessary to add any new genes to coax them to morph into these progenitor cells, Gallicano says. "These are male germ cells as well as adult stem cells. We found that once you take these cells out of the testes niche, they get confused, and will form all three germ layers within several weeks," he says. "These are true, pluripotent stem cells."

The research team took 1 gram of tissue from human testes and produced about 1 million stem cells in the laboratory. These cells showed many of the biological markers that characterize normal beta islet cells.

They then transplanted those cells into the back of immune deficient diabetic mice, and were able to decrease glucose levels in the mice for about a week – demonstrating the cells were producing enough insulin to reduce hyperglycemia. While the effect lasted only week, Gallicano says newer research has shown the yield can be substantially increased.

The research was funded in part by the American Diabetes Association, patient contributions to the GUMC Office of Advancement, support from GUMC diabetes specialist Stephen Clement, M.D., and a grant from GUMC.



Co-authors include Anirudh Saraswathula, a student at Thomas Jefferson High School for Science and Technology in Alexandria, Va. GUMC researchers Shenglin Chen Ph.D., Stephen Clement, M.D., Martin Dym, Ph.D., and Asif Zakaria, Ph.D., also contributed to the research. The authors report having no personal financial interests related to the study.

http://web.resourceshelf.com/go/resourceblog/62554

Medical Library Mobile (MedLibMob): A New Facebook Group & Twitter Stream

December 13, 2010 00:54



The Facebook group/knowledge community was formed by Guus Van Den Brekel a librarian and social media expert at the University Medical Center in Groningen, The Netherlands.

Medical Library Mobile (MedLibMob) is a closed community. However, you can request to join MedLibMob by clicking the button in the upper-right corner of the public page. Of course, you'll need to logged-in to Facebook if/when you ask to join.

MedLibMob also has a Twitter stream at: http://twitter.com/MedLibMob

From a Description of the Group:

Knowledge community for medical libraries on mobile medical libraries & Medical Apps. Exhange info & experience on existing and future Mobile Medical Library Sites, on existing and future content providers supporting mobile, and very important currently, on relevant Medical Apps for any mobile device on any platform out there (iPad, iPhone, Android etc)

Source: @digicmb (via Twitter)

See Also: Skyscape, a well-known provider of mobile medical reference tools, offers a number of FREE apps for iPhone/iTouch/iPad, Android, Blackberry, and other mobile platforms.

Note: Free Apps Require a Skyscape Account (Also Free)
Some Free Apps Are Only Available For Qualified Medical Professionals


http://www.eurekalert.org/pub_releases/2010-12/mcfg-sdt120610.php

Studies detail triumphs, troubles of African innovators creating products for local health needs

Africans strengthen ability to meet health needs in sub-Sahara with homegrown science solutions, but many products stagnate in labs for want of commercialization know-how, support

Global health experts today published a landmark collection of papers that together provide a unique microscope on the experience of countries, companies and organizations in sub-Saharan Africa addressing neglected health problems with homegrown drugs, vaccines, diagnostics and other creative scientific and business solutions.

The first-of-its kind study chronicles the triumphs and troubles of entrepreneurs, institutes and firms in Africa creating innovative, affordable technologies that bring hope to many sufferers of local diseases. While some have yet to succeed, several organizations cleared major hurdles to finance and create products, some of which may expand into global markets one day.

It is the first research offering a broad range of evidence and concrete examples of African innovation to address local health concerns. The papers draw on the experiences of authorities, researchers and entrepreneurs in Ghana, Kenya, Madagascar, Nigeria, Rwanda, South Africa, Tanzania, and Uganda. In addition to efforts involving health products, the experiences of health venture capital funds in African and other developed countries are profiled.

The papers were produced by Canada's McLaughlin-Rotman Center for Global Health (MRC), at the University Health Network and University of Toronto, and published as a special supplement in the UK-based open-access journal publisher BioMed Central Dec. 12 (with full public access at www.biomedcentral.com/bmcinthealthhumrights/10?issue=S1). One of the papers was published earlier in the journal Science. The authors hope their work helps scale up and sustain work underway, while inspiring other organizations and countries to follow suit with the benefit of lessons learned by these African pioneers.

Says MRC Director Peter Singer: "If Africans are to prevail over diseases that kill and maim millions each year, they must do so by unleashing the formidable talents of their own African scientists and entrepreneurs. In the long term, the sustainable solutions to Africa's health problems rest with the home team."

"The large firms of the developed world producing drugs, vaccines, diagnostics and other health products are a great resource and partner. But many people will die if we wait for scientists from elsewhere to invent and market the health products Africa needs. These studies demonstrate that, with the right partners and incentives along with support from governments at home and abroad, Africans have the scientific creativity and entrepreneurial talent to improve local health and prosper at the same time."

"Our message to international agencies, donors and African governments: support these enterprises and nurture their potential, because they can make a major contribution to better health in developing countries – and to their own health. At the end of the day, this is about enabling people to solve their own problems, not only using science but also combining it with entrepreneurship."

Since it began in 2004, the MRC has focused extensively on how low-income countries themselves can remedy diseases of poverty. With relatively little profit incentive, firms in rich, developed countries largely neglect such diseases. The MRC has documented the benefits of the homegrown science approach to health problems, which include, beyond affordable products, less dependency on international donor programs and much-needed new economic opportunities and job creation. This collection represents the MRC's largest contribution to date on product commercialization for improving health in Africa.



Examples of African innovation:

* In Tanzania, local funding, economies of scale, technology transfer, and partnerships all helped the A to Z Textile Company become one of the world's largest producers of long-lasting insecticide treated bed nets, cost-effectively producing tens of millions of nets in an area where malaria is a critical problem. The company succeeded despite regulatory issues, procurement rules, and other barriers.

* In Madagascar, The Malagasy Institute of Applied Research (IMRA) has created Madeglucyl, a treatment for diabetes management based on a traditional remedy;

* In Nigeria, the National Institute for Pharmaceutical Research and Development has a plant-based drug for sickle-cell anemia – one of the few low-toxicity drugs available anywhere to treat the debilitating chronic blood disorder – but has yet to overcome barriers to its commercialization;

"Concern over access to essential medicines have dominated international health policy debates over the last two decades," Harvard professor Calestous Juma says in a preface to the work. The debates, centered on intellectual property rights, wrongly assume that Africa will remain "a marginal player in the world of health innovation and will continue to rely on imported solutions.

"This collection of original papers provides a different prognosis. They reveal an emergent 'health innovation system' in Africa that is driven by a combination of local research, entrepreneurship and institutional adaptations."

The research complements a related MRC paper, published Dec. 10 in Science, about so-called "stagnant technologies" in sub-Saharan Africa – products with the potential to save many lives, but which exist only in a lab due to a failure of commercialization or support.

Led by researcher Ken Simiyu, some 25 such products were identified languishing in health research institutions in Africa, some already validated but not yet converted to a product or service. Of the 25 stagnant technologies found, 16 involved traditional plant products; the rest were new drug molecules, diagnostics, vaccines and medical devices.

They include:

* A low-cost dipstick technology developed at the Noguchi Memorial Institute for Medical Research in Accra, Ghana, for quick, easy, village diagnosis of schistosoma, a parasitic disease that affects more than 50% of people in some areas of Africa.

* An herbal, anti-malarial medicine, Nibima, from a traditional plant Cryptolepis sanguinolenta, under development at the Centre for Scientific Research into Plant Medicines, Ghana

* A product called Sunguprot in Kenya from the plant Tylosema Fassoglensis, whose developers claim it can help manage HIV symptoms. Lack of advanced scientific equipment to isolate compounds and funding to carry out clinical trials have affected further development and validation; and

* An easy-to-use, inexpensive, WHO-approved portable medical-waste incinerator, developed at Makerere University, Uganda, that could solve the problem of hospital waste management in rural areas, especially during mass polio immunization and similar programmes. The incinerator uses no fuel other than the medical waste and achieves temperatures of 800 degrees C.

Meanwhile, at the International Centre for Insect Physiology and Ecology in Kenya, researchers have patented human odors that effectively repel mosquitoes. While there is a need to determine formulations through further research, negotiations are underway with a multinational company.


Among conclusions of the MRC research teams:

* Despite challenges, components of health innovation exist in Africa and, though limited, diverse activity in health innovation is occurring;

* The emerging innovation systems are driven by local health concerns, not external interests. Local, regional and global dynamics affect health innovation;

* Institutions used innovative financing mechanisms and partnerships to their benefit;

* All countries put strong emphasis on plant medicine as a local asset for innovation;

* Fundamental to success are investing in research and development to generate solution-oriented knowledge, providing incentives for entrepreneurs, and building institutional strength to help facilitate commercialization of research results;

* Africa's health innovation systems are increasingly integrated into the global knowledge ecology, and benefit from extensive international partnerships;

* Linkages between groups are sparse to date, but hold potential for building stronger health innovation systems. Business incubation through facilities such as science innovation centers will be an important mechanism for fostering industrial clustering and raising economic productivity.

"Driven largely by entrepreneurs, innovative and affordable technologies to improve health in Africa are under development throughout the continent, with firms using a variety of business models in a range of political environments," says MRC researcher Ken Simiyu.

"Clearly, many Africans have the needed talent and know-how. However, the seeds of their efforts need careful nurturing by both donors and African governments at all levels. Required are creative institutions and coherent policies that reduce risk, build on local strengths, and promote the effective use of local health research."

Says Abdallah S. Daar, MRC Senior Scientist and Director of Ethics and Commercialization: "We are all affected in one way or another by the health and well-being of everyone else on Earth. What we present is a look at many African companies and countries striving to create local health products for local needs. Understanding all aspects of their experiences – what worked, what didn't, and what could have been done better – is a huge leg up for other firms and governments who wish to stand on the shoulders of these pioneers."



The papers in full, to be published (with open public access) will be published Sunday Dec. 12 as a special open-access BMC supplement at www.biomedcentral.com/bmcinthealthhumrights/10?issue=S1

A 25-minute interview on this topic with MRC Director Peter Singer and researcher Ken Simiyu is available online from Dec. 12 at www.mrcglobal.org/projects/african_innovation

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