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Study sheds light on how malaria parasites grow exponentially

A University of South Florida College of Public Health professor and his team of researchers have become the first to uncover part of the mysterious process by which malaria-related parasites spread at explosive and deadly rates inside humans and other animals.

As drug-resistant malaria threatens to become a major public health crisis, the findings could potentially lead to a powerful new treatment for malaria-caused illnesses that kill more than 600,000 people a year.

In a study published online March 3 in the high-impact journal PLOS Biology, the USF researchers and their colleagues at the University of Georgia discovered how these ancient parasites manage to replicate their chromosomes up to thousands of times before spinning off into daughter cells with perfect similitude -- all the while avoiding cell death.

"How these parasites preserve fidelity in this seemingly chaotic process is one of the great mysteries of this pathogen family," said USF Health's Michael White, PhD, a professor in the Department of Global Health who partnered on the study with fellow USF researcher Elena Suvorova, PhD, in the USF Departments of Molecular Medicine Global Health and the Florida Center for Drug Discovery and Innovation, as well as with two researchers from the University of Georgia.

In studying the malaria-relative Toxoplasma gondii, the team found an explanation for that puzzle.

To understand it, consider that malaria-related parasites are professional multipliers, unlike plant and animal species and single-cell organisms like yeast -- where chromosomes get one shot at replication or else the cell dies or turns into cancer, Dr. White explained.

With malaria-related parasites, once transmitted into an animal or human, they can hide out in a single cell in many different tissues replicating silently tens, hundreds or even thousands of times before the host's immune system can detect that they are there.

Then with the stealth of a Trojan horse, they burst forth as "daughter cells," which are unleashed in massive quantities in waves, like a small army into the host's system -- quickly overwhelming a patient's immune response, Dr. White explained.

What the study found was that the Toxoplasma parasites pull this off thanks to a "modified 'control room' called the centrosome that imposes order on the replication chaos," Dr. White said. "Unlike the comparatively simple centrosome present in human cells, the parasite 'control room' has two distinct operating machines; one machine controls chromosome copying, while the other machine regulates when to form daughter cell bodies. Working together, but with independent responsibilities, parasite centrosome machines can dictate the scale and timing of pathogen replication."



This groundbreaking understanding and novel discovery of the centrosome's function leads to a critical conclusion: disruption of the centrosome machines -- like cutting the cables between two computer systems -- kills the parasite, Dr. White said.



Breaking any part of the highly efficient but highly fragile replication functions shuts everything down.

"They are literally Humpty Dumpty," he added. "If they break, they can't be put back together."

With these findings and the new knowledge of the parasites' vulnerabilities, Dr. White and his fellow researchers will delve into drug development.



That process could take anywhere from four to 10 years of further research and clinical trials before a new drug is on the market, he said. The length of time depends on whether the researchers hit upon effective application of prior-FDA approved cancer-related drugs or develop a new treatment from scratch.

Whatever treatment they develop, Dr. White stressed that it will be used in conjunction with other types of drug therapies.



Currently drugs used to treat malaria go after the pathogens' metabolism, while the new research will seek to undermine the parasite's foundation in enough of the spreading cells in order to allow the human immune system to fight back and not become overwhelmed, Dr. White said.

A major challenge today in parts of the world is the lack of access to drug treatments at all or until it is too late and the patient succumbs to malaria-related illnesses and brain hemorrhaging.



Because of the parasite's high-adaptability, current drug treatments are constantly susceptible to the development of drug resistance, Dr. White said.



A potential global health crisis is unfolding as drug-resistant malaria continues to move across Burma, reaching the Indian border, according to British newspaper The Independent, commenting on a recent study in the journal Lancet. Doctors fear it will continue to spread and enter Africa, home to 90 percent of the world's malaria cases.







Malaria caused about 207 million cases and 627,000 deaths in 2012, according to the Centers for Disease Control and Prevention. About 3.2 billion people, or half the world's population, are at risk of malaria, according to the World Health Organization.

Dr. White said that this study, which he called the first for a USF Health laboratory in publishing original research in PLOS Biology, will help get more potential treatments in the pipeline.

"The more we understand their vulnerability," he said of the parasites, "the better chance we can keep that pipeline full."



http://feeds.sciencedaily.com/~r/sciencedaily/~3/kgvWAfWJp5o/150304104552.htm

04 Mar 2015
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How to run Windows programs in a browser tab for free





Most of the time we focus on helpful tips for Windows users, but today's article will also appeal to anyone with a Chromebook. A company named Cameyo is known for its software that lets you run Windows program from a USB stick, but it also offers a virtualization service that lets you run full-blown Windows desktop programs in a browser for free.



Cameyo offers a number of open source programs by default, and if you don't find what you need you can also upload your own EXE files. Cameyo isn't perfect. Virtual programs tend to run slowly, some don't work at all, and using personal files with the apps is not as obvious as it could be.





Nevertheless, Cameyo can come in handy in a pinch when you're away from your primary PC. Here's how it works.

Getting started



The first thing you need to do is sign-up for a Cameyo account and then link your Dropbox account to Cameyo. Once that's done you'll be able to access files that are saved in your Dropbox folder under \Apps\Cameyo\Desktop while you're inside virtualized Cameyo apps. Any files you create while using Cameyo will also be saved back to this location.

In the virtual programs themselves, you'll find your files as though you were navigating through a regular Windows system. In my tests, my files were either under RemoteUser1 or RemoteUser2.

Start a program

cameyoirfanview

Irfanview running in Cameyo.



Firing up a virtual program is simple. Just hover over the program name and click the small play button that appears. The program will start and you can use it as you would on a Windows desktop.

Just remember that when you navigate the file system inside a Cameyo browser program you do not have access to your local files. It's as though you are running a separate Windows system inside your browser. The only way to access or store files is via the desktop for RemoteUser1 or RemoteUser2, which is connected to your Dropbox account if you set things up properly in the previous step.



Cameyo's programs

You'll find a ton of programs you can try out in the browser window, but truth be told only a few truly make sense for casual users. VLC, for example, wasn't worth it in my tests. Any videos I tried to play were choppy and didn't have sound since the virtual app is in its own sandbox with no access to my PC's native audio capability. Plus, if you have a video online that you'd like to watch, it makes more sense to try and view it in a cloud service that offers video streaming for saved files.

Program's I'd recommend trying out in Cameyo are Irfanview for photo editing, 7Zip for compressing files into a zipped format, and Audacity for working with audio files.

Have a look around and you may find other programs that suit your needs. Cameyo is also an excellent place to just try out software without having to download it. And remember you can always try uploading your own EXE files to access specific programs you need.

I wouldn't recommend relying on Cameyo as an everyday solution, but for those times you need quick access to a desktop program from a Chromebook or browser, it's a useful service to know about.



http://www.pcworld.com/article/2891693/how-to-run-windows-programs-in-a-browser-tab-for-free.html#tk.rss_all

03 Mar 2015
Admin · 48 vistas · Escribir un comentario

Personal data on 50,000 Uber drivers exposed in breach





The names and license plate numbers of about 50,000 Uber drivers were compromised in a security breach last year, the company revealed Friday.



Uber discovered a possible breach of its systems in September, and a subsequent investigation revealed an unauthorized third party had accessed one of its databases four months earlier, the company said.



The files accessed held the names and license plate numbers of about 50,000 current and former drivers, which Uber described as a "small percentage" of the total. About 21,000 of the affected drivers are in California. The company has several hundred thousand drivers altogether.



It's in the process of notifying the affected drivers and advised them to monitor their credit reports for fraudulent transactions and accounts. It said it hadn't received any reports yet of actual misuse of the data.







Uber will provide a year of free identity protection service to the affected drivers, it said, which has become fairly standard for such breaches.

The company said it had filed a "John Doe" lawsuit Friday to help it confirm the identity of the party responsible for the breach.



http://www.pcworld.com/article/2890472/personal-data-on-50000-uber-drivers-exposed-in-breach.html#tk.rss_all

01 Mar 2015
Admin · 24 vistas · Escribir un comentario

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