The researchers found evidence that fungi can “lock” depleted uranium into a mineral form that may be less likely to find its way into plants, animals, or the water supply.

“This work provides yet another example of the incredible properties of microorganisms in effecting transformations of metals and minerals in the natural environment,” said Geoffrey Gadd of the University of Dundee in Scotland. “Because fungi are perfectly suited as biogeochemical agents, often dominate the biota in polluted soils, and play a major role in the establishment and survival of plants through their association with roots, fungal-based approaches should not be neglected in remediation attempts for metal-polluted soils.”

The testing of depleted-uranium ammunition and its recent use in Iraq and the Balkans has led to contamination of the environment with the unstable metal, Gadd explained. Depleted uranium differs from natural uranium in the balance of isotopes it contains. It is the byproduct of uranium enrichment for use in nuclear reactors or nuclear weapons and is valued for its very high density. Although less radioactive than natural uranium, depleted uranium is just as toxic and poses a threat to people.

In the new study, the researchers found that free-living and plant symbiotic (mycorrhizal) fungi can colonize depleted-uranium surfaces and transform the metal into uranyl phosphate minerals.

While they probably still pose some threat, he said, “The fungal-produced minerals are capable of long-term uranium retention, so this may help prevent uptake of uranium by plants, animals, and microbes. It might also prevent the spent uranium from leaching out from the soil.”

Gadd said that a combination of environmental and biological factors is involved in the process. First, the unstable uranium metal gets coated with a layer of oxides. Moisture in the environment also “corrodes” the depleted uranium, encouraging fungal colonization and growth. While the fungi grow, they produce acidic substances, which corrode the depleted uranium even further. Some of the substances produced include organic acids that convert the uranium into a form that the fungi can take up or that can interact with other compounds. Ultimately, he said, the interaction of soluble forms of uranium with phosphate leads to the formation of the new uranium minerals that get deposited around the fungal biomass.

“We have shown for the first time that fungi can transform metallic uranium into minerals, which are capable of long-term uranium retention,” the researchers concluded. “This phenomenon could be relevant to the future development of various remediation and revegetation techniques for uranium-polluted soils.”

[Cathleen Genova @ Cell Press]

Though antiretroviral “cocktails” can target an active infection, they cannot get at the virus when it retreats inside the host’s T cells, where it may lie dormant for decades, waiting for an opportunity to burst forth in a fresh round of infection. What HIV hunters need is a good bird dog.

Now, Stanford chemist Paul Wender and his coworkers have found a way to synthesize better bird dogs, agents that can be tailored to flush HIV out into the open where the immune system and antiretroviral therapies can destroy it. Wender is senior author of a paper about the research in the May 2 issue of Science.

“We’re not sure how far this will go, but certainly, from a theoretical point of view, it has promise of taking therapy to the next level???that is, addressing issues related to eradication of the disease, of the virus, at least,” said Wender, the Francis W. Bergstrom Professor.

Wender and his co-workers Jung-Min Kee and Jeff Warrington have developed a way to synthesize prostratin and DPP, two compounds that occur naturally in plants, in the laboratory. Prostratin, found in the Mamala plant (Homalanthus nutans) that grows in the Samoan rainforest, has shown promise in previous studies as an activator of dormant HIV. DPP, a molecular relative of prostratin found in resin spurge (Euphorbia resinifera), which grows in arid regions, also has shown potential.

Research has been hampered, though, because the compounds are difficult to obtain, particularly in the quantities needed for practical lab work on their mode of action and therapeutic potential. The yield from both plants is low and highly variable; the availability of the plants is limited; and isolating the compound is difficult. Heavy harvesting of the wild plants, especially in Samoa, also could cause ecological damage.

But synthetic prostratin and DPP, which now can be readily made in the lab, changes that equation.

“We have now minimized, if not eliminated, the issue of availability of prostratin and DPP,” Wender said. “But equally, if not more importantly, we have opened access to other compounds that might be similar in structure but superior in function.”

Previous work done in mice by researchers at the University of California-Los Angeles indicates that prostratin, used in combination with interleukin-7, an immune system stimulator made in bone marrow, managed to flush out and eliminate approximately 80 percent of the dormant virus. But with HIV, 80-percent efficiency is not enough. Anything less than 100 percent means the virus is still lurking in the T-cells and will spring back to action as soon as an opportunity presents itself.

“Nature has produced these compounds for various reasons in the plants from which they’re derived, but certainly not to treat human maladies,” Wender said. “They’re not optimized for human therapy.”

But with synthetic prostratin and DPP available, researchers can take the basic compounds and tinker with the structure and related function. “We could find out how to improve them by reverse engineering: figuring out what is important and what isn’t important,” Wender said. “We could begin to design and synthesize molecules that would never be found in nature but might actually be therapeutically more beneficial than what has been found thus far.”

In the Science paper, Wender and his team detail how both compounds can be synthesized, but also show the initial phase of designing and making new derivative compounds.

Although prostratin has long been used by traditional Samoan healers without their patients experiencing acute side effects, it is possible that undesirable effects could show up in an immune-impaired patient taking prostratin or DPP. But Wender noted that engineering the compounds in a lab would permit scientists to circumvent these problems. “Usually these kinds of side effects are a result of a drug hitting multiple targets. So it hits one target, which is beneficial, but then it hits some other target, too,” he said. “But by modifying the structures, you could select for the beneficial activity over the non-beneficial activity.”

“It’s a little bit like draw poker,” Wender said. “The important point is that we’re not forced to use the hand we get. We’ll get a hand and we’ll return a few cards if we don’t like it, because we can keep on tuning this until we get it right, so that a royal flush, hopefully, can be realized.”

Wender’s team developed their method of synthesizing prostratin and DPP by using a renewable resource, croton oil, made from the seeds of a small tree (Croton tiglium) cultivated in Asia. They derived phorbol from the croton oil and then converted it into the structure of prostratin.

The conversion process required some engineering finesse; they had to overcome a hurdle when, by removing an oxygen atom, they triggered a series of anticipated but seemingly undesired changes.

“To the credit of my coworkers, Jung-Min Kee and Jeff Warrington, they employed a strategy that sometimes is missed,” Wender said. “Rather than fighting the flow, they went with it.” They found a way to redirect the chemical complications into a solution to the problem that proved even better than the route they had initially sought to follow.

“Eventually they produced a shorter, more economical way of connecting our starting material, phorbol, to our target, prostratin,” Wender said. The process Kee and Warrington came up with requires only five steps, which is of tremendous importance in making it economically feasible. As Wender pointed out, “steps cost money and human time.”

Wender emphasized that the work of his team is the most recent chapter in efforts of a truly global community, starting with the Samoan healers, who willingly shared their knowledge with Paul Cox, an ethnobotanist who saw them prescribing a tea made from Mamala bark for patients with hepatitis-like symptoms. Cox, in turn, sent samples to the National Institutes of Health, in hopes that the bark might have antiviral properties useful in fighting some cancers. Researchers at NIH then analyzed the bark and isolated prostratin.

Prostratin belongs to a class of compounds called tiglianes, many of which promote tumor growth, so it had no initially perceived use in fighting cancer. But NIH researchers found that prostratin was not a tumor promoter and checked to see if perhaps it could help combat HIV, which is when its remarkable ability to flush out the dormant virus was discovered. Significantly, prostratin has also been found to block uptake of the purged virus, offering yet another potentially therapeutic benefit.

“The whole effort is a testimonial to a global community working to deal with what I think is a global, and top priority, problem,” Wender said.

The research was funded by the National Institutes of Health. At the time of the study, Kee was a doctoral candidate in chemistry and Warrington was a postdoctoral scholar at Stanford. Kee is now a postdoctoral scholar at Rockefeller University, and Warrington is working in the biotech industry.

The Joint United Nations Programme on HIV/AIDS estimates that 33.2 million people were living with HIV and 2.1 million people lost their lives to AIDS in 2007. Current antiviral therapies require lifelong treatment, and patients must consistently take doses of medication on a precise schedule, which creates compliance challenges for many of them. The antiviral drugs often become ineffective as the virus develops resistance and are exceptionally costly, the last a major problem in less-developed regions of the globe.

[Louis Bergeron @ Stanford University]

Motorola’s Z9 is a slider phone with a mahogany exterior, which is a nice color to differentiate the Z9 from the rest. The external controls continue to be standard with a volume rocker and music shortcut on the left spine, and a camera shutter and a microUSB port on the right spine. The front packs a gorgeous 2.4-inch display with 262k color support, a crispness that’s required to view today’s digital content, including videos, photos and text. We had a blast navigating through the menu just because the display was so vibrant and exciting to use. Of course similar to a lot of smartphones, you can adjust the brightness and backlighting time to conserve battery, and trust us, with the display this bright, you are almost certainly going to have to work on reducing the brightness.

Going back to the navigation menu, do note that Motorola hasn’t updated its menu at all. It’s the same old way of browsing through your phone. We’re not pleased; half of the fun of getting a new phone is to take advantage of new features, and the Z9 is lackluster in that category.

Underneath the display is your OK button with four corresponding keys for navigation. Additionally, there are two soft keys, Talk/End-Power keys, a Clear-Back key and a Web browser shortcut key to further occupy the rest of the device.

Once you slide open the phone, you are welcomed to its keypad with alphanumeric keys. All keys offer tactile feedback that are difficult to feel. The keys underneath the display, especially, didn’t offer the best tactile feedback that we have experienced. Motorola needs to work on getting the most basic necessities of the phone right.

On the back, you will find the integration camera with its lens and flash. It’s a 2.0-megapixel camera with support for four resolutions (1,600×200, 1,280×960, 640×480, 320×240), three quality settings and 8x digital zoom. Other options, such as lighting (five), color tones (six), and exposure metering are all present. You can also record video in three resolutions (320×240, 176×144 and 128×96) with three quality settings. You can record for up to 30 seconds for MMS clips, or for an unlimited amount of time depending on onboard storage. The phone is equipped with 45MB of onboard storage + a microSD expandable slot for additional memory. There’s a memory meter to alert of you of total available memory, a delightful option.

The Z9 lacks a mirror, so taking self-portraits would be an interesting task at best. The camera quality was decent. It took crisp pictures, but there was some blurriness in them due to dull lighting. Even in the brightest of times, the photo quality didn’t quite get the colors right. While sharp, there were some issues with color contrast in our testing. We would qualify the overall quality to be good with reservations, or decent.

Motorola’s Z9 feels good when you are holding it, as it’s a sturdy, solid unit.

In addition to the onboard camera, it packs an alarm clock, a calendar, text and multimedia messaging and a host of other default, expected features. Most notable is AT&T’s Navigator GPS application, AT&T’s Video Share service, AT&T Music (thanks to 3G support), and a music player with support for MP3, AAC and WMA formats; playlists, shuffle and repeat modes; it also packs a host of mobile multimedia (music, video and weather) services to round out its features set. We liked the feature set in general. Although it’s limited in its potential, Motorola did its best to include as many applications as the phone would hold.

On the performance side, in one word: “Excellent!” The Z9 is an amazing phone with its excellent audio quality. We had no problem understanding callers, or vice versa, thanks to Motorola’s CrystalTalk and auto background noise canceling technology. The phone automatically adjusted our volume depending on extraneous noise, which is something we are greatly fond of with Motorola handsets.

The speakerphone was good, but not quite there with standard output. The volume output was poor, and we really had to focus on what callers were saying to understand them. That defeats the point of turning on the speakerphone option.

Signal strength for 3G was superior and so were audio and video streaming. Though video quality was okay, it was expected. Our videos didn’t pause for buffer or any other technical issues. We loved interacting with our digital control through Z9 and its speedy connection. For some odd reason, however, loading time for music and video files was all over the graph. Some files took longer to load, while others were fairly rapid.

Volume output for audio on the phone was surprising good, especially with a headset.

The Z9 is rated for four hours of talk time and 13 days of standby time. We confirmed these numbers in our lab, and they were inline with the company’s estimates. Four hours is a little iffy for our taste considering it’s a multimedia phone with a handful of battery heavy options.

All in all, the Z9 is a very good phone with solid exterior and a host of features. It’s not the phone for consumers who are looking for mobile innovation, but if you just want a cell phone without a learning curve, but with a bit trendy design, the Z9 is a superb option.

[Gundeep Hora]

This article has been republished with the kind permission of our friends at CoolTechZone. For more news about the gadgets that make the world go ’round, go give ‘em a look or Subscribe to CoolTechZone’s RSS Feed!

Related Articles @ CoolTechZone:

• Virus Protection on Leopard? I Don’t Think So.
• Motorola RAZR V9
• Sony AS50G Headphones Review
• iPhone Competitors: What’s The Point Now?
• Nokia’s Last Effort to Revive N-Gage Fails