December 3, 2007, 10:10 PM CT

Choosing dry or wet food for cats

Eventhough society is accustomed to seeing Garfield-sized cats, obese, middle-aged cats can have a variety of problems including diabetes mellitus, which can be fatal. The causes of diabetes mellitus in cats remain unknown eventhough there has been a strong debate about whether a dry food diet puts cats at greater risk for diabetes. A new study from a University of Missouri-Columbia veterinarian suggests that weight gain, not the type of diet, is more important when trying to prevent diabetes in cats.

Because dry cat food contains more starch and more carbohydrates than canned cat food, some have argued that a diet containing large amounts of carbohydrates is unnatural for a cat that is anatomically and physiologically designed to be a carnivore. Carbohydrates constitute between 30 percent and 40 percent of dry cat food. Some have been concerned that this unnatural diet is harmful to cats and leads to increased occurence rate of diabetes. Wet cat food, conversely, is high in protein and more similar to a natural carnivore diet.

In the study, Robert Backus, assistant professor and director of the Nestle Purina Endowed Small Animal Nutrition Program at MU, and his team of scientists compared a colony of cats in California raised on dry food with a colony of cats in New Zealand raised on canned food. After comparing glucose-tolerance tests, which measures blood samples and indicates how fast glucose is being cleared from the blood after eating, scientists found no significant difference between a dry food diet and a wet food diet. They also compared the results between cats less than three years of age and cats older than three. The MU veterinarian indicated that allowing cats to eat enough to become overweight is more detrimental to their health than the type of food they eat......... Posted by: Kelly      Read more         Source

Tue, 04 Dec 2007 02:02:11 GMT

My Daughter's DNA

Some weeks ago, I presented Hugh Rienhoff, a father who wanted to know what was wrong with his daughter. He had his daughter''s DNA sequenced, then compared it to the human reference sequences in GenBank. And he logged everything at mydaughtersDNA.org. The purpose of the site:

This site is dedicated to expanding our understanding of genetics conditions and variations in the human genome. The primary purpose of the site is to provide a forum for those searching for explanations and the help of the interested community of geneticists, patients, physicians, scientists and family members. Cases that defy explanation, calls for the identification of similar cases, technical problems related to generating valid DNA sequence or genotype information and interpretations of clinical or DNA findings can be posted and interest generated. Of all the questions patients and their doctors ask, three predominate: what is the diagnosis; is there a treatment, who can help. I hope this site can help with those and the other questions.

Now, this incredible man gave a presentation as a part of the Google Tech Talks series. Posted by: Bertalan      Read more     Source

December 2, 2007, 8:36 PM CT

How cells keep in shape

Cells in our body come in various shapes and sizes. Each cell is shaped in such a way as to optimise it for a specific function. When things go wrong and a cell does not adopt its dedicated shape, its function can be impaired and the cell can cause problems in the body. Scientists at the European Molecular Biology Laboratory (EMBL) and the Institute for Atomic and Molecular Physics (AMOLF), The Netherlands, have now decoded a molecular mechanism that plays an important role in the development of a cells shape. In this weeks issue of Nature they report a new experimental approach that sheds light on the interaction between proteins and the cells skeleton.

That each cell type has its unique shape is due to its cytoskeleton, an internal scaffold built of protein filaments. Particularly important are microtubules, dynamic filaments that constantly grow and shrink. Their spatial organisation inside cells depends on a variety of regulator proteins, some of which only interact with the growing ends of these filament. How these so called plus-end tracking proteins recognise the dynamic structure of a growing microtubule end is a long-standing puzzle. Scientists in the groups of Thomas Surrey and Damian Brunner at EMBL and of Marileen Dogetrom at AMOLF have now developed the first method that allows to simultaneously study multiple plus-end tracking molecules, so called +TIPs, in the test tube......... Posted by: Janet      Read more         Source

November 29, 2007, 10:36 PM CT

Seasonal seas save corals with 'tough love'

Finally, some good news about the prospects of coral reefs in the age of climate change. As per a new study by the Wildlife Conservation Society, corals may actually survive rising ocean temperatures in tough love seas with wide-ranging temperatures.

Scientists discovered that coral reefs in sites with varying seasonal temperatures are more likely to survive the hot pulses of Climate Change. On the other hand, reefs living in environments with stable but higher temperatures are more susceptible to bleaching, a global phenomenon where beneficial algae are evicted by corals, ultimately leading to the reefs demise.

The study, which appears in the latest edition of the journal Ecological Monographs, presents the results of an 8-year study on the reefs of East Africa.

This finding is a ray of hope in a growing sea of coral bleaching events and threatened marine wildlife, said Dr. Tim McClanahan, Senior Scientist working for WCS Coral Reef Programs and lead author of the study. With rising surface temperatures threatening reef systems globally, these sites serve as high diversity refuges for corals trying to survive.

Coral reefs are composed of tiny creatures that live in colonies in mostly tropical and subtropical waters. Corals are home to beneficial algae, which gives reefs their stunning colors. During prolonged, uncommonly high surface temperatures, a number of coral species bleach, discharging the algae and leaving the reefs white and sickly......... Posted by: Janet      Read more         Source

November 29, 2007, 4:53 PM CT

New Park in Congo for Bonobos, Elephants and People

The most significant accomplishment in the Democratic Republic of Congo this year was the creation of the Tumba-Lediima Natural Reserve. The new reserve covers 1.9 million acres, an area more than two-and-a-half times the size of Yosemite National Park. Biodiversity surveys conducted by WWF identified critical populations of bonobo and forest elephant in this region.

The park will benefit nearby communities by giving local people a voice in the governance of the region's natural resources. WWF is also initiating an ecotourism program that will share revenues with local communities......... Posted by: Janet      Read more         Source

November 27, 2007, 10:04 PM CT

Image mosaic that will strengthen global forest monitoring

Much of the discussion at the upcoming United Nations Climate Change Conference in Bali, Indonesia, will focus on.

monitoring tropical deforestation and the critical role that remote sensing systems will play in the development of REDD (Reduced Emissions from Deforestation and Degradation) mechanisms policies designed to compensate rainforest nations for avoiding deforestation. Using synthetic aperture radar (SAR) data acquired over a six-week period by the Japanese Advanced Land Observing Satellite (ALOS), researchers at the Woods Hole Research Center have just completed the first-of-its-kind, large-scale, wall-to-wall image mosaic at 25 m resolution for a portion of the Amazon basin.

spanning some 400,000 square kilometers. Images acquired globally over narrow timeframes provide for true snapshots of deforestation activities, giving leverage to monitoring programs that hinge on timely and accurate observations of forests throughout the world.

Dr. Josef Kellndorfer, who is leading the project for the Center, says, The Japanese Space Agency JAXA has launched an amazing sensor which exhibits unprecedented geometric and radiometric accuracies allowing us to generate high quality cloud free radar image mosaics with nearly no user interaction required. The ALOS observation plan will ensure,......... Posted by: Erica      Read more         Source

November 26, 2007, 3:24 PM CT

Summer-dormant tall fescue grass shows promise

A pasture improvement research program by Dr. Dariusz Malinowski has him looking at summer-dormant tall fescue grasses as an alternative to winter wheat pastures.

But these arent the typical tall fescue grasses grown in a number of parts of the nation, said Malinowski, a Texas Agricultural Experiment Station forage agronomist in Vernon. They are from the Mediterranean Basin of southern Europe and northern Africa.

Our climate is changing here, he said. Its been getting warmer and drier since the mid-90s.

This climate change has made wheat-grasses and wheat pasture a less-viable option than in the past, Malinowski said. In his search for a replacement option, summer-dormant cool-season perennial grasses that start turning green and grow with the first rains in September are showing the most promise.

The Mediterranean summer-dormant cool-season perennial grasses such as tall fescue, orchardgrass, ryegrass and hardinggrass grow under conditions of mild winters and hot, dry and long summers, he said.

At one time, the southern Great Plains had its peak rainfalls in May and September, but that precipitation pattern doesnt exist now, Malinowski said.

This year is one of the a number of examples, he said. Wheat is not growing because there has been no moisture. So we think these perennial summer-dormant grasses are a viable option......... Posted by: Erica      Read more         Source

November 24, 2007, 8:18 AM CT

New scenario for first life on Earth

A team led by the University of Colorado at Boulder and the University of Milan has discovered some unexpected forms of liquid crystals of ultrashort DNA molecules immersed in water, providing a new scenario for a key step in the emergence of life on Earth.

CU-Boulder physics Professor Noel Clark said the team observed that surprisingly short segments of DNA, lifes molecular carrier of genetic information, could assemble into several distinct liquid crystal phases that self-orient parallel to one another and stack into columns when placed in a water solution. Life is widely believed to have emerged as segments of DNA- or RNA-like molecules in a prebiotic soup solution of ancient organic molecules.

A paper on the subject was reported in the Nov. 23 issue of Science. The paper was authored by Clark, Michi Nakata and Christopher Jones from CU-Boulder, Giuliano Zanchetta and Tommaso Bellini of the University of Milan, Brandon Chapman and Ronald Pindak of Brookhaven National Laboratory and Julie Cross of Argonne National Laboratory. Nakata died in September 2006.

Since the formation of molecular chains as uniform as DNA by random chemistry is essentially impossible, Clark said, researchers have been seeking effective ways for simple molecules to spontaneously self-select, chain-up and self-replicate. The new study shows that in a mixture of tiny fragments of DNA, those molecules capable of forming liquid crystals selectively condense into droplets in which conditions are favorable for them to be chemically linked into longer molecules with enhanced liquid crystal-forming tendencies, he said......... Posted by: Janet      Read more         Source

November 21, 2007, 5:23 AM CT

Evolution-tracking method to discover 300 new human genes

Using supercomputers to compare portions of the human genome with those of other mammals, scientists at Cornell have discovered some 300 previously unidentified human genes, and found extensions of several hundred genes already known.

The discovery is based on the idea that as organisms evolve, sections of genetic code that do something useful for the organism change in different ways.

The research is reported by Adam Siepel, Cornell assistant professor of biological statistics and computational biology, Cornell postdoctoral researcher Brona Brejova and his colleagues at several other institutions in the online version of the journal Genome Research, and it will appear in the December print edition.

The complete human genome was sequenced several years ago, but that simply means that the order of the 3 billion or so chemical units, called bases, that make up the genetic code is known. What remains is the identification of the exact location of all the short sections that code for proteins or perform regulatory or other functions.

More than 20,000 protein-coding genes have been identified, so the Cornell contribution, while significant, doesn't dramatically change the number of known genes. What's important, the scientists say, is that their discovery shows there still could be a number of more genes that have been missed using current biological methods. These methods are very effective at finding genes that are widely expressed but may miss those that are expressed only in certain tissues or at early stages of embryonic development, Siepel said......... Posted by: Janet      Read more         Source

November 21, 2007, 4:45 AM CT

Ripening secrets of the vine

Whether you prefer a Cabernet Sauvignon or a Pinot Noir grape variety, two new research articles reported in the online open access journal, BMC Genomics, offer a host of new genetic information on fruit ripening for this economically important fruit crop.

The grapevine's gene expression analysis reveals two distinct molecular and functional phases that correspond with the green and red grape stages. And scientists have reported the first biochemical evidence that reactive oxygen species accumulate during the colour transition. Stefania Pilati and fellow scientists from the IASMA Research Center, San Michele all'Adige, Italy, investigated ripening Pinot Noir grapes (Vitis vinifera L.) to identify fruit ripening genes and investigate seasonal influences. They found a core set of more than 1,400 ripening-specific genes that fluctuated similarly across three growing seasons and a smaller gene group strongly influenced by climatic conditions.

During the green berry (pre-vraison) phase, numerous genes involved in hormonal signalling and transcriptional regulation were modulated, suggesting large-scale cellular metabolism reprogramming. Auxin, ethylene and light played pivotal roles. During the following ripening (post-vraison) phase, genes for cell-wall organization and biogenesis, carbohydrate and secondary metabolisms, and stress response came into play, whereas photosynthesis was strongly repressed. These transcriptional events tally with the processes of berry softening and accumulation of sugar, colour and aroma compounds, which ultimately determine berry and wine quality. At vraison, the intervening point when grapes slow down their growth and change colour, this study highlighted an oxidative burst involving hydrogen peroxide (H2O2), and an extensive modulation of the enzymatic anti-oxidative network......... Posted by: Erica      Read more         Source