Friday, February 8, 2008

Rotunda Management Meetings



Hi friends, we are rushing towards another weekend and also on the cusp of getting our fresh re-certification audit done for the ISO 9001-2000 standards for our clinic. Everyone is working hard towards the goal. Just found a nice cartoon in NY times about our management meetings.
Have a nice weekend, folks.

Thursday, February 7, 2008

Lab on a Chip Medical Breakthrough


It's common knowledge that to carry out genetic tests, one would need expensive, state-of-the-art laboratory. But that might soon change thanks to a group of Canadian scientists who've developed a "lab-on-a-chip" device to conduct these tests. What is interesting about the device is that it's supposed to be portable, inexpensive, and efficient.

Hailing from the University of Alberta; Professor Christopher Backhouse and Professor Linda Pilarski (Department of Oncology), along with research student, Govind Kaigala, have developed a $1,000 device the size of a shoebox that can conduct genetic tests and deliver results in less than half an hour.

Elaborating on the innovation, the researchers said that miniaturization is the key factor that has drastically brought down the cost of this gadget.

The Canadian Press quoted Professor Backhouse as saying that like computers, which in their early days, were inaccessible; somewhat like million-dollar beasts who formed a roomful, yet one needed a Ph.D. to to be able to operate one of them.

Similarly, the Professor said Life Science technologies do exist but aren't being utilized optimally because they're very expensive. Hence, the key to this mini-laboratory was to integrate, shrink, and automate. The ability of the device to implement a very wide range of tests on a standard platform quickly and inexpensively would make it indispensable for the future.

The research team believes that their miniature lab-on-a-chip will provide Cancer patients with quick genetic tests, in turn speeding up treatment processes. The team also believes the device may be useful in finding genetic signatures for particular viruses or bacteria or for testing the quality of water, and so on.

Wednesday, February 6, 2008

Sperm From Female Stem Cells


British scientists have created early-stage, human sperm from female stem cells, according to a news report in New Scientist magazine. It is claimed that the research will pave the way for same sex couples to have children that are genetically their own. However, other scientists are sceptical that this procedure would ever be possible.
Professor Karim Nayernia at the University of Newcastle initially fertilised mice with sperm derived from embryonic stem cells (ESCs) in 2006, which gave rise to seven pups, six of which survived. In more recent work, he took human male stem cells from bone marrow and formed 'spermatogonia', primitive sperm cells that can form mature sperm cells by going through a process called meiosis. Nayernia has now apparently done the same using human female stem cells, work that has yet to be published.
The next stage in the process would be to make these primitive sperm cells undergo meiosis, which Nayernia claims he has started to do. The result could be that female eggs are fertilised by 'female' sperm, thereby eradicating the need for male gametes. However, Dr Robin Lovell-Badge, a stem cell expert at the National Institute of Medical Research in London, does not think the approach will work. He told the Telegraph newspaper that the 'presence of two X chromosomes is incompatible with this. Moreover they need genes from the Y chromosome [from the male sperm] to go through meiosis. So they are at least double damned'. Safety issues have also been raised, since the mice pups in Nayernia's initial study had health problems.
A Brazilian team of scientists lead by Dr Irina Kerkis at the Butantan Institute in Sao Paolo also claim to have made sperm and eggs from male mouse ESCs, and are currently starting to take the work into human cells. The research brings hope to people dealing with infertility, a problem that affects one in six couples, although scientists say the process is still in its infancy and treatments are a long way off.
There is also potential to use 'induced pluripotent stem cells', stem cells derived from human skin cells, as a starting point for the process. This could enable gay men to donate skin cells that would be used to create stem cells from which eggs could be formed. The eggs could then be fertilised using sperm from his partner, and placed in a surrogate mother.
Greg Aharonian, a patent analyst in the US, is trying to patent the technology behind 'female' sperm and 'male' eggs. A self-proclaimed 'troublemaker', he wants to undermine the argument that marriage should remain heterosexual because its main purpose is procreation.
The controversial developments have provoked mixed responses in the UK and US. Mike Judge from the Christian Institute faith group says that 'children need male and a female role models'. Many religious groups still oppose gay marriage. Josephine Quintavalle, from the pro-life lobby group Comment on Reproductive Ethics, says: 'we are looking at absurd solutions to very obscure situations and not addressing the main issue. Nobody is interested in looking at what is causing infertility - social reasons such as obesity, smoking and age'.

Tuesday, February 5, 2008

Less Dud, More Stud Sperms


The University of Michigan's sperm sorter consists of a penny-size silicon chip divided into two channels. Semen is dripped onto one side, a saline solution on the other. Where the channels meet, the healthy, or motile, sperm swim over to the saline channel, leaving the dead or slow sperm behind. The healthy sperm are then collected for in vitro fertilization. University of Michigan scientists have developed a new technique to sort out the swimmers from the duds in semen, which could lead to a more efficient way for men who suffer from low sperm counts to make babies.

Current methods use centrifugation, which spins the sperm at very high speed. But the technique isn't efficient because live sperm are pelted with dead ones, causing a significant number of viable sperm to die in the separation. "We can harvest motile sperm from samples where there is a low number without causing any damage to the sperm," said team member Dr. Gary Smith, associate professor of obstetrics and gynecology at the University of Michigan Health System.

In men with healthy sperm counts, each ejaculation contains about 200 million to 400 million sperm. For these men, in vitro fertilization using centrifugal separation is relatively easy because it only takes 10 million to 20 million motile sperm to fertilize an egg in a petri dish. But men with low sperm counts have had less success. "For men with very low sperm count, these other techniques are often unable to recover any motile sperm," said Shuichi Takayama, assistant professor in the Biomedical Engineering program at the University of Michigan, where the new sorter is being developed. Other methods to pinpoint live sperm in a low sperm sample require a microscope and a lot of patience. The new sperm sorter may put an end to this laborious hand sorting. "It may mean that instead of having a well-trained technician, you could have one that is not so well-trained," said Dr. Mark Surrey, of the Southern California Reproductive Center in Beverly Hills.

So far the sorter has fared well in trials. In one test the team used a sample in which only 44 percent of the sperm was motile. After going through the sorter, the count of motile sperm went up to 98 percent. The sorter employs microfluidics, a branch of physics and biotechnology that examines the microscopic flow of fluids. Within the device everything is pushed downstream by gravity and surface tension. The Michigan team notes, however, that more tests are needed before the sorter becomes a mainstay in doctors' offices. Smith said he expects it will be ready for clinical use in one to two years.

Monday, February 4, 2008

Swiss experts say individuals with undetectable viral load and no STI cannot transmit HIV during sex

Swiss HIV experts have produced the first-ever consensus statement to say that HIV-positive individuals on effective antiretroviral therapy and without sexually transmitted infections (STIs) are sexually non-infectious. The statement is published in this week’s Bulletin of Swiss Medicine (Bulletin des médecins suisses). The statement also discusses the implications for doctors; for HIV-positive people; for HIV prevention; and the legal system.

The statement’s headline statement says that “after review of the medical literature and extensive discussion,” the Swiss Federal Commission for HIV / AIDS resolves that, “An HIV-infected person on antiretroviral therapy with completely suppressed viraemia (“effective ART”) is not sexually infectious, i.e. cannot transmit HIV through sexual contact.”

It goes on to say that this statement is valid as long as: the person adheres to antiretroviral therapy, the effects of which must be evaluated regularly by the treating physician, and the viral load has been suppressed (< 40 copies/ml) for at least six months, and there are no other sexually transmitted infections.

The article begins by stating that the Commission “realises that medical and biologic data available today do not permit proof that HIV-infection during effective antiretroviral therapy is impossible, because the non-occurrence of an improbable event cannot be proven. If no transmission events were observed among 100 couples followed for two years, for instance, there might still be some such events if 10,000 couples are followed for ten years. The situation is analogous to 1986, when the statement ‘HIV cannot be transmitted by kissing’ was publicised. This statement has not been proven, but after 20 years’ experience its accuracy appears highly plausible.”

For example, they note, Quinn and colleagues found that in sero-discordant couples the risk of transmission depended on the viral load of the HIV-positive partner, and refer also to a prospective study of 393 heterosexual sero-discordant couples from Castilla and colleagues found that there were no infections among partners of persons on antiretroviral therapy, compared to a rate of transmission of 8.6% among partners of untreated patients. They also note that transmission from mother to newborn also depends on the maternal viral load, and can be avoided by taking antiretroviral therapy.

They go on to assert that effective antiretroviral therapy eliminates HIV from genital secretions. They say that HIV RNA, measured in sperm, declines below the limits of detection on antiretroviral therapy, and that HIV RNA is also below the limits of female genital secretions is, as a rule, during effective antiretroviral therapy. “As a rule,” they write, “it rises after, not before, an increase in plasma viral load.” They also assert that although cell-associated viral genomes are present in genital secretions, even on antiretroviral therapy, these are not infectious virions since “HIV-containing cells in sperm lack markers of viral proliferations such as circular LTR-DNA.”

They note that the concentration of HIV RNA in sperm correlates with the risk of transmission and that “transmission risk declines towards zero with falling sperm viral load. These data indicate that the risk of transmission is greatly decreased by antiretroviral therapy.”

They add, however, several exceptions and caveats to the above statements:
After a few days or weeks of discontinuation of antiretroviral therapy, plasma viral load rises rapidly. There is at least one case report of transmission during this rebound.

In patients not on treatment, STIs such as urethritis or genital ulcer disease increase the genital viral load; it falls again after the STI is treated.

In a patient with urethritis, sperm viral load can rise slightly even while the patient is receiving effective treatment. This rise is small, however, much smaller that the rise observed in patients not on treatment.

They conclude the scientific part of the article by saying that: “During effective antiretroviral therapy, free virus is absent from blood and genital secretions. Epidemiologic and biologic data indicate that during such treatment, there is no relevant risk of transmission. Residual risk can not be scientifically excluded, but is, in the judgment of the Commission, negligibly small.”

Implications for doctors
The Commission then discusses the implications for doctor-patient discussions. It says, "the following information aims to communicate to doctors criteria allowing them to establish whether or not a patient can sexually transmit HIV.

HIV cannot be transmitted sexually if:
The HIV-positive individual takes antiretroviral therapy consistently and as prescribed and is regularly followed by his/her doctor.

Viral load is ‘undetectable’ and has been so for at least six months

The HIV-positive individual does not have any STIs."


Implications for HIV-positive people
The Commission states that an HIV-positive person in a stable relationship with an HIV-negative partner, who follows their antiretroviral treatment consistently and as prescribed and who does not have an STI, is "not putting their partner at risk of transmission by sexual contact."

"Couples must understand," they write, "that adherence will become omnipresent in their relationship when they decide not to use protection, and due to the importance of STIs, rules must be defined for sexual contacts outside of relationship."

"The same goes for people who are not in a stable relationship," they add. However due to the importance of STIs, use of condoms is still recommended.

They add that heterosexual women will have to consider eventual interactions between contraceptives and antiretrovirals before considering stopping using condoms.

They also say that insemination via sperm washing is no longer indicated when "antiretroviral treatment is efficient."

Implications for HIV prevention
The Commission says that it "is not for the time being, considering recommendations that HIV-positive individuals start treatment purely for preventative measures." Aside from the cost involved, they argue, it cannot be certain that HIV-positive people would be sufficiently motivated to follow, and apply to the letter, antiretroviral treatment on a long-term basis without medical indications. They note that poor adherence is likely to facilitate the development of resistance, and that, therefore, antiretroviral therapy as prevention is indicated only in "exceptional circumstances for extremely motivated patients."

The Commission also says that their statement should not change prevention strategies currently taking place in Switzerland. With the exception of stable HIV-positive couples where HIV-positivity and the efficacy of antiretroviral therapy can be established, measures to protect oneself must be followed at all times. "People who are not in a stable relationship must protect themselves," they note, "as they would not be able to verify whether their partner is positive or on efficient antiretroviral therapy."