My Biotechnology

Of mice and men's (and women's) contraceptives

2005-05-09T13:15:00.000-07:00

Study of unique reproductive-cell protein in mice could lead to new contraceptives for women and men

(Philadelphia, PA) – Mice lacking a special protein found only in germ-line cells results in infertility in both males and females, according to a new study from researchers at the University of Pennsylvania School of Medicine.
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Animals deficient in the protein – called MSY2 – are infertile, but are otherwise healthy and completely normal. Male mice produce no functional sperm, and females show early loss of eggs and defects in ovulation.
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"...We think the absence of the MSY2 protein causes problems in the timing of sperm or egg development. ..."
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EUREKALERT

Will we see an absolutely new contraceptive? It's possible.

Sugar coating improves anticancer treatment

2005-05-09T11:50:00.000-07:00

Sweet nanoparticles successfully deliver drugs to mouse tumours

A coating of sugar could help nanoparticles deliver molecules to fight widespread tumours, according to research on mice.
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The research team says its treatment could be adapted to a range of cancers and could move to clinical trials in two years' time.

The nanoparticles, which are small enough to pass through blood vessels into the surrounding tissue, are taken up by cancerous cells because they carry a molecular tag that binds to receptors found on tumours. The agent consists of small interfering RNA (siRNA). When the agent is taken up by a tumor cell, it inhibits expression of the tumour-growth gene, and the cell stops multiplying.

NATURE

I wish it helps. What else can I say?

Modified mice live longer

2005-05-08T14:33:00.000-07:00

A mouse with the ability to mop up free radicals at the cellular level - and live longer as a result - has been created by scientists.

The research is a boost for the free radical theory of ageing. This proposes that reactive oxygen species damage cells and tissues, leading to declining health and, eventually, death.

“We hope that in future years, this knowledge can be applied to deliver similar benefits to humans,” says lead researcher Peter Rabinovitch, a pathologist working on ageing at the University of Washington, Seattle, US.

The results may also encourage those on the fringes of mainstream research who long for immortality.

The transgenic mice Rabinovitch’s team created produce higher-than-normal levels of the antioxidant enzyme catalase. Cells use catalase to convert damaging hydrogen peroxide to harmless water and molecular oxygen, but the enzyme is usually found only in the cytoplasm of cells.

His team made mice that produce high levels of catalase in their mitochondria, the powerhouses of cells. They found that cellular damage, as well as age-related damage in the heart, decreased in comparison to control mice that produced catalase in just cytoplasm or in cell nuclei. The lifespan of the mitochondria-catalase mice was extended by more than five months - an increase of around 20%.

NEW SCIENTIST

Immortality... hmmm...

Pheromone attracts straight women and gay men

2005-05-07T14:27:00.000-07:00

Smelling a male pheromone prompts the same brain activity in homosexual men as it does in heterosexual women, a new study has found. It did not excite the sex-related region in the brains of heterosexual males, although an oestrogen-derived compound found in female urine did.

The testosterone-derived chemical AND is found in male sweat and is believed to be a pheromone. It activated the anterior hypothalamus and medial preoptic area of gay men and straight women alike. Researchers led by Ivanka Savic at the Karolinska University Hospital in Sweden believe this brain region integrates the hormonal and sensory cues used in guiding sexual behaviour.

The research demonstrates a likely link between brain function and sexual orientation, Savic suggests. But she told New Scientist that the study “does not answer the cause-and-effect question”. So the brain-activation of gay men by AND may contribute to sexual orientation of those men, or simply be the result of their orientation and sexual behaviour. She added that the brain scans revealed no anatomical differences between any of the participant’s brains.

NEW SCIENTIST

They are different. I knew it.

First clone of champion racehorse

2005-04-19T12:09:00.000-07:00

The first ever clone of a champion racehorse was unveiled on Thursday at a press conference in Italy. The foal was cloned from a skin cell of Pieraz, a multiple world champion in equine endurance races of up to 50 kilometres.

Unlike conventional horseracing, which bans the use of non-natural methods of breeding, including cloning, endurance racing is among the half dozen or so equine sports which would allow cloned competitors. Others include dressage, showjumping, three-day-eventing, polo and carriage horse racing.

It is the first time an elite racehorse has been cloned, and comes two years after the appearance of Prometea, the first and only other cloned horse.
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It's getting more and more interesting. I don't touch the subject of morality here, my blog is only about technology and science.
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NEW SCIENTIST

HIV-infected cells made to self-destruct

2005-04-18T22:54:00.000-07:00

HIV = Small green bodies; Human tissue cell = Large blue body

Targeting a protein which helps repair DNA damage in human cells could provide a new way of fighting HIV infection, new research suggests. Crucially, harnessing this approach might offer a way of combating multi-drug resistant strains of HIV which are becoming increasingly common.

Most HIV drugs work by targeting proteins produced by the HIV virus itself. But because HIV has a short life-cycle and readily mutates, the proteins it produces quickly evolve to become resistant to these antiretroviral drugs.

Now, a new “proof of concept” study shows that blocking one of the key cellular proteins which regulates a cell’s response to DNA damage can stop HIV hijacking it and using it to manufacture thousands more copies of itself.

Inhibiting the protein - called ataxia-telangiectasia-mutated (ATM) - in human cells exposed to HIV in the lab stopped the virus from splicing itself into many of the exposed cells’ DNA and instead triggered their demise.

“By targeting ATM we are stopping the infected cell from producing more virus,” says Mark O’Connor, project leader and head of biology at Kudos Pharmaceuticals Limited in Cambridge, UK. “The most exciting thing is the study demonstrates the proof of concept that targeting a cellular factor required for HIV replication, but not itself essential to the cell, allows you to overcome the problem of drug resistant HIV.”
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It's a new approach. I hope it will work some day. Cool stuff.
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NEW SCIENTIST

Malaria Membrane Protein Structure

2005-04-15T19:53:00.000-07:00

Apical membrane antigen 1 (AMA1) is an integral membrane protein in malaria-causing Plasmodium parasites and is currently in clinical trials against P. falciparum, the species that causes the most serious forms of malaria in humans. Although AMA1 is essential for host cell invasion, its molecular function is unknown. Pizarro et al. (p. 408, published online 24 February 2005) have solved the crystal structure of the three-domain ectoplasmic region of AMA1 from P. vivax at 1.8 angstrom resolution. Domains I and II belong to the PAN motif, a protein fold that functions in receptor binding.
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It's difficult to read, I know.
These people are amazing. It's very hard job to crystallize these proteins, that's why I think it's wonderful.
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SCIENCE

Improving the nutritional value of Golden Rice through increased pro-vitamin A content

2005-04-13T15:44:00.001-07:00

'Golden Rice' is a variety of rice engineered to produce -carotene (pro-vitamin A) to help combat vitamin A deficiency1, and it has been predicted that its contribution to alleviating vitamin A deficiency would be substantially improved through even higher -carotene content2. We hypothesized that the daffodil gene encoding phytoene synthase (psy), one of the two genes used to develop Golden Rice, was the limiting step in -carotene accumulation. Through systematic testing of other plant psys, we identified a psy from maize that substantially increased carotenoid accumulation in a model plant system. We went on to develop 'Golden Rice 2' introducing this psy in combination with the Erwinia uredovora carotene desaturase (crtI) used to generate the original Golden Rice1. We observed an increase in total carotenoids of up to 23-fold (maximum 37 g/g) compared to the original Golden Rice and a preferential accumulation of -carotene.
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There was a pretty nice article on BBC news several years ago.
I do beleive that moddified products are not going to solve the problems of poor countries. It's a question of working economy and politics only.
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NATURE

Fastest DNA Computer

2005-04-10T08:37:00.000-07:00

A biomolecular computer that uses little more than DNA and enzymes could perform a billion operations simultaneously, say scientists led by Ehud Keinan of the Technion- Israel Institute of Technology in Haifa.

Three years ago, a joint team from Technion and the Weizmann Institute of Science in Rehovot, Israel, published a paper in Nature on a DNA-based computer. But the machine was limited to only 765 simultaneous programs and, unlike this new system, it required human supervision.

The new biomolecular computer is described in the March 2005 issue of the Journal of the American Chemical Society. Computations are carried out by processing the input (double-stranded DNA molecules) with the help of enzymes that chop and reassemble the DNA in a series of steps. The output is in the form of a slightly altered DNA molecule.

The system's complexity "is certainly novel and [has] never been achieved before," says Natasha Jonoska, a mathematician at the University of South Florida, Tampa.

Pinpointing and Killing Cancer Cells

2005-04-07T12:34:00.000-07:00

Breast cancer cell

A Korean research team has developed a way to selectively age and kill cancer cells for the first time in the world.

The team led by Yonsei University biology professors Cheong In-gwon (47) and Lee Tae-ho (49) announced on April 3, saying, “We are the first to confirm the fact that cancer cells stop growing and start aging and eventually die when the gene ‘MKRN1’ is injected into them.”
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“This research was done in the lab, but it is as good as having developed an actual therapy since we’ve experimented on human cancer cells instead of those of rats,” Professor Cheong said.
Cheong anticipated, hence, good results from the clinical tests soon to be performed on real cancer patients.

The research result is reported in the latest edition of the famous biotech magazine: “Genes and Development.”

LINK

Sex selection for human embryos backed by report

2005-04-05T14:35:00.000-07:00

LET them choose boys! Or girls! That's what parents in the UK should be free to do, according to a parliamentary committee. Its controversial report calls for a relaxation of the rules on the use of reproductive technologies and human embryo research.

The report recommends that parents on IVF programmes be allowed to use pre-implantation genetic diagnosis to select the sex of a second or later child for "family-balancing" reasons. It is also unfair for IVF clinics to screen would-be parents to try to exclude child abusers, it says.

If accepted, the report's recommendations would bring the UK more in line with the US, where decisions on the use of reproductive technology are largely left to individuals. And although human embryo research is a major political issue in the US, there are few restrictions on it there, other than a block on federal funding.

The committee chairman, MP Ian Gibson, admits that the recommendations will not please everyone. "I'm sure George Bush would burn the report," he says.

Even some members of the committee may feel the same. Only half signed the report, and the dissenters made it clear that they think it too libertarian.

NEW SCIENTIST

'Gene-editing' technique cuts out diseased DNA

2005-04-04T21:00:00.000-07:00

A gene-editing process that corrects mutations without weaving foreign genetic material into the chromosome has been demonstrated in diseased human cells for the first time. It could provide a less risky and more efficient alternative to gene therapy, which has resulted in leukaemia in some patients.

A team led by scientists at Sangamo Biosciences in Richmond, California, US, say they have corrected the single gene mutation that causes the fatal X-chromosome-linked severe combined immune deficiency (X-SCID)
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Even though I'm in biochemistry, I still cannot believe what people can do with genes.
I hope to see real medical experiment in 20-30 years. I'm too optimistic. :)
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NEW SCIENTIST

Money for Microbiology

2005-04-02T20:57:00.000-08:00

Seventy-seven intramural scientists at the National Institutes of Health (NIH) have joined calls for more funding of nonbiodefense microbiology.
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It affects a lot of people in science, unfortunately. I heard, that the chances to win NIH grant decreased two times to compare to the last year.
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SCIENCE

Membraneless fuel cell created

2005-04-02T18:13:00.000-08:00

A fuel cell that promises to be both cheaper and more efficient than existing designs has been developed by Paul Kenis of the University of Illinois at Urbana-Champaign. In a typical fuel cell, one chamber contains fuel that reacts across a porous membrane with oxygen in a second chamber, liberating electrons that provide electrical power. Kenis's system does away with the membrane by exploiting a phenomenon known as "laminar flow", where tiny streams of liquid behave so viscously they do not mix when squeezed past one another. That not only simplifies the cell's design, but might lead to efficiency increases of up to 40 per cent.
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I hope to see these fuel cells in stores. I'm a little sceptical about it.
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NEW SCIENTIST

Black holes don't exist

2005-04-01T14:15:00.000-08:00

George Chapline (Lawrence Livermore National Laboratory) thinks that the collapse of the massive stars, which was long believed to generate black holes, actually leads to the formation of stars that contain dark energy. "It's a near certainty that black holes don't exist," he claims.
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This news has nothing to do with biotech, but it's just amazing that we all believe in facts which are not proven yet.

NATURE

Crystal structure of a membrane-bound metalloenzyme

2005-03-29T11:52:00.000-08:00

Particulate methane monooxygenase (pMMO) is an integral membrane metalloenzyme that catalyses the conversion of methane to methanol. ...
We have determined the structure of pMMO from the methanotroph Methylococcus capsulatus (Bath) to a resolution of 2.8 Å.
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It's rare when people crystallize membrane proteins. It's very hard. That's why this work was published in "Nature".

NATURE

Biologists come close to cloning primates

2005-03-29T11:44:00.000-08:00

Cloned monkey embryos transferred into mothers.

US biologists have created cloned monkey embryos, and successfully transferred them into monkey mothers. Although none of the resulting pregnancies lasted more than a month, this is by far the closest scientists have come to cloning a primate.

This work was done in University of Pittsburgh, Pennsylvania

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NATURE

Magnetic Cells ?

2005-03-23T14:36:00.000-08:00

A new technique that creates tiny magnets in cells may enable MRI scans to visualize gene expression in living organisms. The technique may also one day help scientists visualize therapeutic gene delivery in humans.
At present, gene expression is imaged with the help of "reporters" such as green fluorescent protein, which causes cells to fluoresce when specific genes are turned on. But the technique is limited to the areas of the body that light can penetrate, like the skin. As an alternative, scientists have considered using magnetic resonance imaging (MRI), which detects differences in magnetic fields between tissues. But because the magnetic fluid injected into the body in traditional MRI does not penetrate well into cells and tissue, this method also prevents scientists from visualizing cells deep within the body.
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SCIENCE

X chromosome activity different in every woman

2005-03-22T13:09:00.000-08:00

Baffling variations between women have emerged from an X chromosome study - some females may get an overdose of X genes

UNEXPECTED and baffling variations between individual women have emerged from a study of the X chromosome.

While men have one X and one Y chromosome, women have two X chromosomes. If all the genes on both X chromosomes were active, women would get an overdose of the proteins these genes code for. To prevent this, every cell in the early female mammalian embryo switches off one of its X chromosomes, which then remains silent in all the descendants of that cell - a process called X inactivation.
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NEW SCIENTIST

US bans Synthesis of Smallpox Virus

2005-03-17T08:36:00.000-08:00

Congress has slapped new restrictions--and hefty penalties--on one type of study involving the most dreaded pathogen on Earth. By adding a last-minute amendment to a massive intelligence reform bill in October, Representative Pete Sessions (R-TX) has made it illegal for most U.S. researchers to synthesize the smallpox virus, variola, from scratch.
...Only two labs in the world, one in Russia and one in the United States, can store and study variola...

SCIENCE

X chromosome

2005-03-16T11:50:00.000-08:00

THE complete sequence of the human X chromosome was published in Nature this week. The work shows that large segments of it match parts of normal chromosomes in birds, confirming the X chromosome's "non-sex" origins.

Blindness risk is in your genes

2005-03-16T11:47:00.000-08:00

PEOPLE with a particular variant of an immune-system gene have a much higher risk of suffering from age-related macular degeneration, the main cause of blindness in the elderly. The mutant gene might be responsible for up to half of the many millions of cases worldwide.
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NEW SCIENTIST

Irresistible Lure for Cockroaches Determined

2005-03-15T08:29:00.000-08:00

The sex pheromone of the German cockroach, Blattella germanica, has been characterized as gentisyl quinone isovalerate.
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SCIENCE

Premature Ageing

2005-03-14T14:33:00.000-08:00

SKIN cells taken from children with the premature ageing syndrome Hutchinson-Gilford progeria have been restored to normal. The work proves it is possible to compensate for the genetic defect that causes this cruel disease, but finding ways to do this in the entire body remains a big challenge.
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LINK

Smoke damages baby's DNA

2005-03-14T14:28:00.000-08:00

Pregnant women who smoke risk damaging their baby's DNA. The phenomenon, which has long been suspected, was confirmed by a study reported this week in the Journal of the American Medical Association (vol 293, p 1212). Compared with non-smoking mothers, researchers found four times as many structural abnormalities in chromosomes from fetal cells when the mother smoked.

LINK

Ecstasy may trigger gene-linked depression

2005-03-14T14:22:00.000-08:00

IF YOU have a family history of depression, you should probably think twice about taking ecstasy. The drug appears to trigger depression in people with a genetic susceptibility to the condition.

Ecstasy tricks neurons into dumping large quantities of the mood-regulating neurotransmitter serotonin into the brain. It is thought to work by causing serotonin transporters to reverse direction, pumping serotonin out of neurons instead of sucking it back in.
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LINK

Fetal DNA extracted from mother's blood

2005-03-13T13:31:00.000-08:00

Rare genetic diseases could be detected without amniocentesis.

A non-invasive blood test can now detect the gene for the fatal disease beta-thalassemia in a growing fetus. Its developers believe that the technique could be applied to a range of other diseases, overcoming the need for a more invasive procedure called amniocentesis.

Screening a mother's blood can already determine whether unborn children have certain hereditary diseases. But current screens can only detect large-scale irregularities in the baby's chromosomes, such as those found in Down syndrome, says Sinuhe Hahn, a molecular biologist from the University Women's Hospital in Basel, Switzerland.
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LINK

Potatoes pack a punch against hepatitis B

2005-03-12T17:27:00.000-08:00

Genetically modified potatoes can deliver the disease protection that normally comes from a vaccine shot, say scientists, which could be good news for developing nations.
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Participants in the study had already received the primary injections against hepatitis B between 1 and 15 years ago. Arntzen and his colleagues found that 19 of the 33 people in their study produced more antibodies against hepatitis B after eating the potatoes.
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The fact that the vaccine worked in nearly 60% of the participants came as good news.

LINK