Friday, November 04, 2005

Microsoft acquires Foldershare

The good news just keeps pouring. Microsoft recently announced it is acquiring file-sharing firm Foldershare http://www.foldershare.com (See: http://www.anandtech.com/news/shownews.aspx?i=25212) How does it make a difference to me, you ask? I'll get to it in a bit. I've been using the Foldershare technology ever since they offered their software as free Beta to the users over Internet. If you were familiar during the heady days of Internet there used to be small company named Audiogalaxy that allowed you to share your music files in a very unique way. They'd a small application known as Satellite that you could use to upload and download music. Well, Audiogalaxy was later shutdown due to threats of lawsuits from Music Industry (ala Napster). They pulled the plug on the website. However, the technology evolved into a new tool called Foldershare.

Now, Foldershare was and is a neat tool. It's unique till date to my knowledge. It lets you synchronize your files across multiple computers. If you're anything like me, you have some documents and pictures taken from Digital Camera in your laptop, Some music in your home computer etc., How do you keep all these synced up? In comes Foldershare, it lets synchronize files across the computers you use. You can also invite friends to download/upload files from your library. I was using Foldershare actively till it was a free service. Now thanks to Microsoft acquiring the company it's once again Free!! Free as in Free Beer!! Go ahead and give it a try (http://www.foldershare.com) You wouldn't believe how you lived without it.

Thursday, October 27, 2005

Biology news 5: Bird flu

With bird flu on the horizon, this is the time to learn about it. I'll try to explain it in simple terms. You can learn more at www.cdc.gov/flu/avian/.

What is bird flu, or avian influenza? First of all, it is important to know that there are different strains of flu in the world. There are the ones that infect humans, the ones that infect pigs, the ones that infect horses, and the ones that infect birds, to name a few.

The type that infects birds, the scary one we are talking about, is called H5N1. It right now is causing a bird flu outbreak in Asia. A lot of birds are dying, and possibly passing on the flu in a rare case of transmission to humans.

Normally, viruses from birds don't infect humans. They can only infect birds because birds have right proteins on their cells to let the virus enter. Humans don't. The way that the virus could infect humans is to mutate and somehow find a way to enter human cells. Even then, it has to make the human sick enough (at least a cold) to pass on the virus to other humans. Only then will there be an epidemic.

Why is H5N1 killing all of these birds NOW? H5N1 is different from other bird flu strains because it has changed. While normal bird flu only infects the intestines and the airways of birds, H5N1 can infect intestines, eyes, airways, and many other organs. This means that rather than just a normal flu-like symptom or ruffling of feathers in birds, the birds can die.

What will happen if bird flu gets into humans? Infection of humans could mean you get just a plain old flu, or something more serious like an airway attack, or even death. Because humans have never seen a virus like this before (Our usual influenza is really different from bird flu), our immune systems don't know how to attack the virus to stop it. So it could possibly have a stronger effect.

What about a vaccine? Groups are now working on trying to get medicines and vaccines for H5N1, in case of an outbreak. The vaccines that are being tried right now require a lot more killed virus than the normal flu vaccine. When one is developed, people may need to get more than one shot to prevent disease. Vaccines are now in trials.

How can we prevent it? Stay away from birds, if you can! Don't eat raw eggs or uncooked poultry. Avoid travel to places that have known outbreaks of avian flu, or at least stay away from poultry farms and any contact with animals there. And when any flu vaccine becomes available - get it! If you get any flu-like symptoms it's probably just the regular flu, so wash your hands frequently, see your doctor, and get plenty of rest. Don't cough on anybody!

Monday, August 29, 2005

Biology news 4: Taming Cholesterol

We're back. In this issue, as you munch on festival sweets and cakes, biologists bring you new insights into a scary aspect of diet: cholesterol. You can read the actual article here: http://www.pubmedcentral.gov/articlerender.fcgi?tool=pubmed&pubmedid=16100574.

There's a lot of bad hype about cholesterol: it can cause heart problems, you want to keep your numbers low, and it can lead to a bigger gut (along with its ugly cousin, fat). But cholesterol can be good for you, too.

We all need a little bit of cholesterol to keep our cells working properly. Cholesterol is a small molecule that slips into the outer wall (the cell membrane) of the components of our bodies, our cells. In there, it helps keep the cell membrane fluid and smooth, not rigid and impenetrable. If you have too little cholesterol, your liver will actually start to make it!

The problems start when you have too much. Too much cholesterol can combine with fat to clog up arteries.

So it's important that your liver stops making cholesterol. How does your body know that there's too much cholesterol and to stop making it? That's something scientists have puzzled over, until now.

Recent studies have shown that when you have too much cholesterol, two genes in your DNA get turned on. They make two proteins called the "Insigs." What are insigs and what do they do? The Insig proteins are special in one particular way: they prevent cholesterol from being made by binding to one of the parts of the cholesterol-making machine.

Imagine: you eat a particularly high cholesterol diet (a large fast-food lunch, or several slices of pizza with lots of cheese). You get a lot of cholesterol into your cells. In the meantime, your body has already been making cholesterol! That's cholesterol you don't need. A machine in your cell is chugging away, making cholesterol, with cholesterol-making proteins.

Now, your insigs spring into action. They go over to the cholesterol-making protein (called SREBPs), and they grab on to it. They glom on and trap it inside the cell so that it can't make more cholesterol-making proteins and more cholesterol. Ta da - you stop making cholesterol. Of course, now you have to do something with the cholesterol you already have.

What happens when your insigs stop working? The scientists removed the insig genes from some mice. When those mice ate a lot of cholesterol-rich food (mmm, cheese!), they got fat. Of course. But not only that! They continued to make cholesterol even when their livers would normally stop.

The cool thing about this study is that if you could treat people who normally make too much cholesterol with something that activates their insigs, they would make less. Then you could someday even increase your insigs to prevent from getting fatty!

Tuesday, July 26, 2005

Biology news 3: Cats don't have a sweet tooth

The third in the series might surprise you: it turns out that cats can't taste sweetness! Anyone who's ever tasted cat food knows it certainly isn't sweet. If you want to read details, see here: http://genetics.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pgen.0010003.

It turns out that most ordinary (that is, tame pet) cats have normal taste, but they can't taste sweetness. This is not true of humans of course, but most other mammals, including dogs, mice, horses, etc. can all tell when something is sweet. Cats can't! And scientists have wondered why for a long time.

How do you know what tastes sweet? Your tastebuds on your tongue detect sugar or sweet compounds (in honey, nutrasweet, splenda) and send a signal to your brain that says, "Hey, that's sweet!" The tastebuds have little proteins on them called receptors that actually attach to sugar molecules and then get turned on to send the message to your brain. When your tongue is burnt, you can't taste anything, because those receptors on your tongue are temporarily missing!

So why can't cats taste the sweet? It turns out their DNA for the sweetness receptor is ok. The sweetness receptor is actually a pair of proteins called "taste receptor 2" and "taste receptor 3." Taste receptor 3 is fine in cats, but taste receptor 2 isn't. Even though the DNA is there, there are changes in it (called mutations) that mess it up so that it never makes it to the cat's tongue. This kind of gene for taste receptor 2, which is actually there but not turned on, is called a pseudogene. With only half of a sweetness detector, the cats can't tell what's sweet and what isn't.

Amazingly, domestic cats aren't the only ones with the problem. Lions, cheetahs, jaguars and tigers can't taste sweet either. Somewhere along in evolution, one ancient cat lost the ability to taste sweetness, and so all its descendants did, too.

What does this mean for cats? Well, there's no point tempting them with sugar in their milk, for one thing. But also, it might explain why cats are carnivores. Since fruit and veggies don't taste good to them, they might prefer the flavor of meat. Or it could be the other way around: maybe because they started eating meat, they lost their sweet tooth.

In any case, it's a mystery, and makes taste even more interesting. In fact, even among humans, only some of us can taste certain types of bitterness (like phenylthiocarbamide, PTC, which is in cigarettes). With lots of taste receptors on our tongues, some people really do have "good taste."

rani

Thursday, June 09, 2005

Biology news 2: Male and female dinosaurs

The second in the series is an interesting one: now you can tell which dinosaurs are male and which are female. The story is here: http://www.sciencemag.org/cgi/content/abstract/308/5727/1456

So, how can you tell a girl dinosaur apart from a boy? If you had a whole dinosaur, it would be easier: you could look at reproductive organs, which ones laid eggs, who raises the kids, who wears lipstick, etc. But scientists don't have the luxury of observing whole, live dinosaurs. They don't even have whole, dead ones. All they have is fossilized bones!

So, we have to use something else to tell which one is male and which is female. The typical methods used relative size to tell if an animal was male, and it was usually not very reliable (so, that huge, scary T rex you saw at the museum might have been a mommy or a daddy!).

Now, scientists have found a Tyrannosaurus rex in the Rockies that they know for sure is a female. A fertile female. One who was laying eggs.

How do they know? Well, it turns out that when female dinosaurs are laying eggs, they change the inside of the bones in their back legs. The coolest thing about this is that birds do the same thing!

In current-day birds (especially ostriches and emus), when the girl birds start to make eggs, their hormones (like estrogen) go up, and they make this lining on the inside of their bones. The lining has calcium in it that helps them make eggshells. Amazingly, only birds do this.

So what does this mean? Well, for one it means that any dinosaur that has this special type of bone lining is definitely a female. It means the female was laying eggs.

And it also means something else: it means that dinosaurs are related to birds, especially ostriches and emus! So next time you see an ostrich at the zoo, remember: its great-great-great-great-great-great... grandmother could have been a T rex!

rani

Tuesday, May 17, 2005

Biology news 1: Antibodies protect against HIV

Hi everyone,

As a biologist, I feel I need to educate people about biology and what the latest news is. We'll start with a simple discovery: that certain antibodies can protect against HIV infection. A full description is here: http://www.nature.com/news/2005/050509/full/050509-2.html

What is HIV? Well, it is the virus that causes AIDS (no doubt about that). In AIDS, the cells in your body that kill the bad things (viruses, bacteria, worms) are themselves killed by the virus. So when you have AIDS you get really sick because your own internal army is destroyed and you're not strong enough to fight off other infections.

What are antibodies? Well, they are proteins (like the protein you eat) that are made inside your body, but they are shaped like a Y. The Y shape is useful because these antibodies can attach to other proteins - for example, they could latch on to a bacteria that's infected you (food poisoning), or some poison you accidentally touched (poison ivy), or in this case, a virus. When the antibodies attach to the virus, they can drag the virus away so that your body can kill it. The antibodies are like harpoons and hooks that your body can use to grab on to the viruses and destroy them.

So, it may come as no surprise that antibodies can prevent HIV from growing. But in fact it is, because for the longest time, people have had a hard time finding antibodies that work in people who have AIDS. In fact, most of the antibodies that AIDS patients have don't do anything to the virus! They just sit there floating around, maybe attaching a little, but then the virus changes and the hooks don't attach anymore.

In this study, what the scientists did was give people specific antibodies (particular Y shapes that attach to particular proteins) that would attach to HIV. They found that if you gave the patients the antibodies, the HIV didn't grow as fast as it did when you didn't give the antibodies or if you gave them random Y shapes that attach to something else.

The new study is exciting because it says that some antibodies that we could give to patients might help prevent the virus from growing inside a person. They aren't very strong, and they don't work as well as the other drugs that doctors usually give people with HIV in the US, so they will probably be part of a combined treatment, but it might be another bit of hope for people outside the US who can't get drugs very easily.

Also, the antibodies working might mean that other ways of helping a person make more antibodies might be useful in the fight against AIDS.

rani

Have you tried the RSS feeds on My Yahoo! website?

Now you can customize your My Yahoo pages with RSS feeds for various websites. You can even have different pages for different categories. You can aggregate all the News websites you want in one page, All Tech-related feeds in a second page, Bargains and Deals in the third page and so on. RSS aggregation on My Yahoo! really makes life easy for many of us who do not have visit each website individually to see if there's a content of interest to us. Now you can know that simply by opening your My Yahoo! Page. I strongly suggest you give it a try.

Here's what you need to do to try this out. Go to http://my.yahoo.com and sign in with your Yahoo ID and password. Choose 'Add Content' link on the 'My Yahoo' page and you'll be directed to the page where you add content to your 'My Yahoo' page. Apart from a bunch of tools provided by Yahoo, you're also allowed to choose your own RSS feeds. Type in your search terms in the Text Box next to 'Find Content' to discover news sources. Try adding the following URL in the Text box and try it out: http://tekzon.blogspot.com/atom.xml

--Rajesh