Now scientists know why. According to a study released Wednesday, the egg-laying critter is a genetic potpourri — part bird, part reptile and part lactating mammal.

The task of laying bare the platypus genome of 2.2 billion base pairs spread across 18,500 genes has taken several years, but will do far more than satisfy the curiosity of just biologists, say the researchers.

“The platypus genome is extremely important, because it is the missing link in our understanding of how we and other mammals first evolved,” explained Oxford University‘s Chris Ponting, one of the study’s architects.

“This is our ticket back in time to when all mammals laid eggs while suckling their young on milk.”

Native to eastern Australia and Tasmania, the semi-aquatic platypus is thought to have split off from a common ancestor shared with humans approximately 170 million years ago.

The creature is so strange that when the first stuffed specimens arrived in Europe at the end of the 18th century, biologists believed they were looking at a taxidermist’s hoax, a composite stitched together from the body of a beaver and the snout of a giant duck.

But the peculiar mix of body features are clearly reflected in the animal’s DNA, the study found.

The platypus is classified as a mammal because it produces milk and is covered in coat of thick fur, once prized by hunters.

Lacking teats, the female nurses pups through the skin covering its abdomen.

But there are reptile-like attributes too: females lay eggs, and males can stab aggressors with a snake-like venom that flows from a spur tucked under its hind feet.

SOURCE

The bird-like qualities implied by its Latin name, Ornithorhynchus anatinus, include webbed feet, a flat bill similar to a duck’s, and the gene sequences that determine sex. Whereas humans have two sex chromosomes, platypuses have 10, the study showed.

“It is much more of a melange than anyone expected,” commented Ewan Birney, who led the genome analysis at the European Bioinformatics Institute in Cambridge.

The animal also possesses a feature unique to monotremes — an order including a handful of egg-laying mammals — called electroreception.

With their eyes, ears and nostrils closed, platypuses rely on sensitive electrosensory receptors tucked inside their bills to track prey underwater, detecting electrical fields generated by muscular contraction.

“By comparing the platypus genome to other mammalian genomes, we’ll be able to study genes that have been conserved throughout evolution,” said senior author Richard Wilson, a researcher at Washington University.

In captivity, platypuses have lived up to 17 years of age.

In the wild, they feed on worms, insect larvae, shrimps and crayfish, eating up to 20 percent of their body weight every day.

Males grow to a length of 50 centimetres (20 inches) and weigh about two kilos (4.5 pounds), with females about 20 percent shorter and lighter.

The genome sequenced for the study belongs to a female specimen from New South Wales nicknamed Glennie and can be accessed at www.ncbi.nih.gov/Genbank.

Now scientists know why. According to a study released Wednesday, the egg-laying critter is a genetic potpourri — part bird, part reptile and part lactating mammal.

The task of laying bare the platypus genome of 2.2 billion base pairs spread across 18,500 genes has taken several years, but will do far more than satisfy the curiosity of just biologists, say the researchers.

“The platypus genome is extremely important, because it is the missing link in our understanding of how we and other mammals first evolved,” explained Oxford University‘s Chris Ponting, one of the study’s architects.

“This is our ticket back in time to when all mammals laid eggs while suckling their young on milk.”

Native to eastern Australia and Tasmania, the semi-aquatic platypus is thought to have split off from a common ancestor shared with humans approximately 170 million years ago.

The creature is so strange that when the first stuffed specimens arrived in Europe at the end of the 18th century, biologists believed they were looking at a taxidermist’s hoax, a composite stitched together from the body of a beaver and the snout of a giant duck.

But the peculiar mix of body features are clearly reflected in the animal’s DNA, the study found.

The platypus is classified as a mammal because it produces milk and is covered in coat of thick fur, once prized by hunters.

Lacking teats, the female nurses pups through the skin covering its abdomen.

But there are reptile-like attributes too: females lay eggs, and males can stab aggressors with a snake-like venom that flows from a spur tucked under its hind feet.

SOURCE

The bird-like qualities implied by its Latin name, Ornithorhynchus anatinus, include webbed feet, a flat bill similar to a duck’s, and the gene sequences that determine sex. Whereas humans have two sex chromosomes, platypuses have 10, the study showed.

“It is much more of a melange than anyone expected,” commented Ewan Birney, who led the genome analysis at the European Bioinformatics Institute in Cambridge.

The animal also possesses a feature unique to monotremes — an order including a handful of egg-laying mammals — called electroreception.

With their eyes, ears and nostrils closed, platypuses rely on sensitive electrosensory receptors tucked inside their bills to track prey underwater, detecting electrical fields generated by muscular contraction.

“By comparing the platypus genome to other mammalian genomes, we’ll be able to study genes that have been conserved throughout evolution,” said senior author Richard Wilson, a researcher at Washington University.

In captivity, platypuses have lived up to 17 years of age.

In the wild, they feed on worms, insect larvae, shrimps and crayfish, eating up to 20 percent of their body weight every day.

Males grow to a length of 50 centimetres (20 inches) and weigh about two kilos (4.5 pounds), with females about 20 percent shorter and lighter.

The genome sequenced for the study belongs to a female specimen from New South Wales nicknamed Glennie and can be accessed at www.ncbi.nih.gov/Genbank.

The revolutionary drug Viagra also known as Revatio, that changed lives of countless number of men and women instantaneously becomes 10 year old this month.

The drug we know as Viagra was not intended and was discovered serendipitously(accidentally) by a team working in the research laboratory of the drug giant Pfizer.

They were testing Sildenafil, the main constituent(Sildenafil citrate) of Viagra, for cardiovascular diseases. Amusingly,what happened was that some of the volunteers in the clinical trial phase dint want to give the medicine back even after the clinical trial was over. The drug improved their sex lives,they were experiencing amazing (read: harder) and longer erection.

Thus the “Blue Pill” was born. The drug was patented in 1996 and FDA approved it on March 27,1998 for using it in treatment of ED(Erectile Dysfunction) or impotence. It became an instant hit, its annual sales for the period 1999-2001 crossed $1 billion.

It “induces” erection by dilating the blood carrying vessels to the penis and hence facilitates the blood flow which results in erection.

The pill is generally taken prior to eating anything and it starts working in about 30 mins and its effect last for about 4 hours. The dosage varies with prescription.

It also has common side effects like sneezing, headache, flushing, dyspepsia, palpitations and photophobia. Besides the usefulness, its enormous popularity resulted in misuses also.

Some people also dont like the idea for being “programmed” for love making!

Thea and Phil Willson became the proud parents of Daniella, Alexis and Gemma on February 29, 10 weeks before the babies’ expected due date.

Naturally born identical triplets are born at a rate of one in 20 million, said Michael Bernard of Fraser Health, the regional health authority that oversees the hospital where the baby was delivered.

Most triplets are conceived with the help of fertility drugs, but the Willsons did it naturally.

“We were totally shocked,” Thea Willson said, recalling her reaction when she first discovered she would be the mother of three.

“Now we’re just really happy we have all three of them and they are all healthy,” she said Thursday. What else can you say, we’re really thankful.”

Thea Willson was able to hold her daughters for the first time on Wednesday. The babies weigh between 910 grams and 1.5 kilograms, and are expected to remain in the hospital at least until their original due date, in early June.

Selena Mohammad, a spokesman for neonatal services at Royal Columbian Hospital in New Westminster, where the babies were delivered, says even veteran staff members are awestruck.

“The rarity, it’s amazing, it’s huge,” Mohammad said. Thea Willson took it in stride as she joked about her new family.

“We’ve always wanted to have more than one. So we had them all at once, she said.

From

In the fruit fly, Drosophila pseudoobscura, about half the sperm are infertile. Why waste energy producing dud sperm? Luke Holman and Rhonda Snook of the University of Sheffield, UK, may have the answer.

They measured how long sperm survived inside the reproductive tract of the female, which contains sperm-killing chemicals. They found that the more parasperm there was in the ejaculate, the longer the fertile sperm survived. “They forgo reproduction to help their brothers,” says Holman.

There is an infertile sperm “caste” in other fly species, and in butterflies and moths, and Holman suggests they may perform the same sacrificial function. Male humans seem to have evolved an alternative strategy, however. “The most conspicuous adaptation is seminal fluid, which has pH buffers and suppresses female immune activity,” says Holman.

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Baby girl,who has 5 legs will be operated upon to remove her extra leg.Another of her limb which is said to be deformed will also be removed.

The 18 month old cat was found wandering on the streets of Canonsburg, Pennsylvania, U.S.She walks on three legs only.

She is currently under the care of Washington Area Humane Society. They say her legs could be a result of in-breeding.

The workers say,”Baby girl” would be put for adoption.

Anyone?

By using a process called whole organ decellularization, scientists from the University of Minnesota Center for Cardiovascular Repair grew functioning heart tissue by taking dead rat and pig hearts and reseeding them with a mixture of live cells. The research will be published online in the January 13 issue of Nature Medicine.

“The idea would be to develop transplantable blood vessels or whole organs that are made from your own cells,” said Doris Taylor, Ph.D., director of the Center for Cardiovascular Repair, Medtronic Bakken professor of medicine and physiology, and principal investigator of the research.

Nearly 5 million people live with heart failure, and about 550,000 new cases are diagnosed each year in the United States. Approximately 50,000 United States patients die annually waiting for a donor heart.

While there have been advances in generating heart tissue in the lab, creating an entire 3-dimensional scaffold that mimics the complex cardiac architecture and intricacies, has always been a mystery, Taylor said.

It seems decellularization may be a solution – essentially using nature’s platform to create a bioartifical heart, she said.

Decellularization is the process of removing all of the cells from an organ – in this case an animal cadaver heart – leaving only the extracellular matrix, the framework between the cells, intact.

After successfully removing all of the cells from both rat and pig hearts, researchers injected them with a mixture of progenitor cells that came from neonatal or newborn rat hearts and placed the structure in a sterile setting in the lab to grow.

The results were very promising, Taylor said. Four days after seeding the decellularized heart scaffolds with the heart cells, contractions were observed. Eight days later, the hearts were pumping.

“Take a section of this ‘new heart’ and slice it, and cells are back in there,” Taylor said. “The cells have many of the markers we associate with the heart and seem to know how to behave like heart tissue.”

“We just took nature’s own building blocks to build a new organ,” said Harald C. Ott, M.D., co-investigator of the study and a former research associate in the center for cardiovascular repair, who now works at Massachusetts General Hospital. “When we saw the first contractions we were speechless.”

Researchers are optimistic this discovery could help increase the donor organ pool.

In general, the supply of donor organs is limited and once a heart is transplanted, individuals face life-long immunosuppression, often trading heart failure for high blood pressure, diabetes, and kidney failure, Taylor said.

Researchers hope that the decellularization process could be used to make new donor organs. Because a new heart could be filled with the recipient’s cells, researchers hypothesize it’s much less likely to be rejected by the body. And once placed in the recipient, in theory the heart would be nourished, regulated, and regenerated similar to the heart that it replaced.

“We used immature heart cells in this version, as a proof of concept. We pretty much figured heart cells in a heart matrix had to work,” Taylor said. “Going forward, our goal is to use a patient’s stem cells to build a new heart.”

Although heart repair was the first goal during research, decellularization shows promising potential to change how scientists think about engineering organs, Taylor said.

“It opens a door to this notion that you can make any organ: kidney, liver, lung, pancreas – you name it and we hope we can make it,” she said.

Researchers of the Center for Cardiovascular Repair team were assisted in their study by researchers from the University of Minnesota Department of Biomedical Engineering, who helped analyze data.

The study was funded by the Medtronic Foundation Endowment and a faculty research development grant from the University of Minnesota Academic Health Center.

Source

Researchers removed DNA from donated human eggs, and replaced it with DNA from the skin cells of two volunteers.

They produced embryos with genetic material that matched the men’s, but did not go on to extract stem cells.

UK experts say the research, published in the journal Stem Cells, is a small but not a great step forward.

The team at Stemagen Corporation in La Jolla, California, says the work could be an important stage in developing embryonic stem cells for patients.

The group produced five embryos called blastocysts from 25 donated eggs. DNA fingerprinting proved that at least one of these was a clone.

“We’re the first in the world to take adult human cells and then document that in fact we were able to clone embryos from them,” lead researcher Dr Samuel Wood told the BBC.

He said the embryos were destroyed in the process of verifying they were clones, but they were now working on creating stem cell lines.

Dr Lyle Armstrong of Newcastle University is one of a handful of other researchers who have made cloned human embryos using a technique known as nuclear transfer pioneered in Dolly the sheep. Unlike the US team, the Newcastle group used DNA from embryonic rather than mature tissue.

Dr Armstrong said the US study showed that the objective of using cells from an adult person to make individual stem cells might one day be possible.

“It’s a small step but not a great step forward,” he told BBC News. “It’s interesting that they’ve been able to repeat somatic cell nuclear transfer and get embryos of the stage where embryonic stem cells could be derived, but it is disappointing that they’ve failed to derive a stem cell line.”

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