Research: AIDS damages brain in 2 ways

The AIDS virus damages the brain in two ways, by not only killing brain cells but by preventing the birth of new cells, U.S. researchers reported on Wednesday.

The study, published in the journal Cell Stem Cell, helps shed light on a condition known as HIV-associated dementia, which can cause confusion, sleep disturbances and memory loss in people infected with the virus.

It is less common in people taking drug cocktails to suppress the virus, and why HIV damages brain function is not clearly understood.

The virus kills brain cells but it also appears to stop progenitor cells, known as stem cells, from dividing, the team at Burnham Institute for Medical Research and the University of California at San Diego found.

"It's a double hit to the brain," researcher Marcus Kaul said in a statement. "The HIV protein both causes brain injury and prevents its repair."

The cocktail of drugs known as highly active antiretroviral therapy or HAART that treats HIV does not infiltrate the brain well, allowing for a "secret reservoir" of virus, said Stuart Lipton, who worked on the study.

HIV-associated dementia is becoming more common, as patients survive into their older years.

Working in mice, the researchers found that the virus directly interferes with the birth of new brain cells from stem cells.

AIDS virus prevents stem cells in the brain from dividing; it hangs them up.
The culprit is gp120 -- a protein found on the outside of the AIDS virus, the researchers found.

"Knowing the mechanism, we can start to approach this therapeutically," Lipton said.

"This indicates that we might eventually treat this form of dementia by either ramping up brain repair or protecting the repair mechanism," Kaul added.

Read more...

Wiki as a textbook in class room

At many colleges and universities, wikis are used mostly as a supplement to primary teaching tools like textbooks and labs.

In one Boston College professor's classroom, however, wikis have become a primary learning tool, replacing textbooks and allowing improved collaboration among students. The wiki is even used to let students submit possible questions for examinations, many of which actually appear on tests.

Gerald Kane, assistant professor of information systems at the Chestnut Hill, Mass., school, has been using a wiki from SocialText Inc. as the primary teaching tool in his classroom since October, relying on the technology to integrate content from other Web 2.0 technologies like social book-making tools, RSS systems, and Google for his "Computers in Management" courses.

For example, before students submit papers to Kane, they can post them on the wiki to be reviewed by other students.

"The students are able to revise them before they submit them into me for grading," he said. "I went back and compared students who revised papers based on peer feedback to those who didn't. Those who did got a grade bump higher."

In addition, Kane does not write his own exam questions, but instead allows students to post suggested exam questions and submit answers to the wiki. Other students can edit the answers if they feel they are wrong. Some 350 exam questions have been generated using this tactic, he said.

"For the last couple of sessions, 100% of the exam has come from student questions," Kane added. "Students see the entire test beforehand but they don't know what questions I am going to [use]."

Some recent research surveys have found that some companies are investing in wikis, but the technology is used less heavily than other Web 2.0 tools like RSS feeds and social networks. For example, only 33% of executives surveyed by McKinsey & Co. for a report issued in March said that their companies are investing in wiki technologies. The survey concluded that companies are investing more heavily in Web services, RSS, podcasts, social networking and peer-to-peer networking

But Kane noted that because the wiki is collaborative and dynamic -- he and his students can update it as quickly as world events change -- it is a much better classroom tool than a texbook.

"My wiki is my textbook now," he said. "This platform is infinitely better and gets better information from a variety of sources. It takes a year and half for a textbook to get published, and by the time that happens it is outdated. [The use of] textbooks will begin to fade ... and these more collaborative-based, environment will probably rise to the surface."

Read more...

Microsoft to increase the hotmail storage limit

Microsoft is increasing the storage limit for its Web-based e-mail service, surpassing competitor Google's limit but far short of Yahoo's unlimited storage.

The limit for a free Windows Live Hotmail account will increase from 2GB to 5GB. The change will be rolled out to users over the next few weeks along with a series of other upgrades, wrote Ellie Powers-Boyle, a Microsoft program manager, on a company blog.

Google offers around 2.8GB of storage space for a free account. Last week, Google began selling storage space that can be used for either its Gmail or Picasa photo sharing services for $20 a year for another 6GB as well as more expensive plans.

Under the new changes, Microsoft will let users store 10GB of e-mail data for a $14.99 annual subscription. Those subscribers will also get a new feature: the ability to forward e-mail from their Hotmail account to a Gmail or other e-mail account.

Unfortunately, users of the free service will only be able to forward e-mail from one Hotmail account to another Hotmail account, essentially blocking them from a quick migration to another free e-mail service.

Another new Hotmail option is the ability to shut off the "Today" feature, which shows top news and features stories on Microsoft's MSN portal. It appears after a user logs into their Hotmail account.

Microsoft is also changing some of Hotmail's security features. One new feature is a link, "Report phishing," that alerts Microsoft to a possible scam Web site linked to an e-mail.

Microsoft is trying to make Hotmail run faster. The company will also increase the amount of time that messages are stored in the junk and deleted items folders before being automatically flushed, although no specific time period was given.

Other improvements include: Better performance for Hebrew and Arabic writers, a feature that stops the duplication of contact information, and the ability to set an automated response.

Read more...