Archive for June 2007
HIV introduces its genetic material permanently into the DNA of body cells. In particular, the white blood cells are important as permant source of dormant viral genetic information, decreasing in number by every reactivation of virus production. The teams of Joachim Hauber from the HPI and Frank Buchholz from the MPI-CBG, Hamburg, did sucessfully remove viral DNA from infected cells. “We got rid of the virus from the infected cells; nobody has done this before”, the scientists claimed.
To achieve this result they genetically engineered a recombinase, an enzyme that works like molecular scissors. Recombinases cut and paste DNA sequences at specific sites. “Naturally occurring recombinases do not recognize viral sequences and are therefore not useful for an anti-viral approach”, said Buchholz: “So we had to develop a recombinase that recognizes the viral sequence and removes the virus with precision.”
The molecular biologists started from a recombinase that naturally is found in a bacteriophage. This enzyme, termed “Cre”, does not recognize sequences from the HIV genome. Using the forces of evolution the scientists used more than 120 generation cycles to breed the enzyme “Tre”, which is now able to recognize HIV sequences.
“Although Tre has so far only been tested in tissue culture cells, this work lays the technical foundation for a novel therapeutic approach that one day might be used to eradicate the HIV from cells of infected patients” said Hauber. However, it is still a long way until this approach can be used in clinical practice. “We will first go back to the bench to further improve the enzyme and then test whether the recombinase can be delivered efficiently and safely to cells in the human body,” said Buchholz and Hauber.
Mind, if these results should be confirmed and developped successfully, an appropriate means of application of this principle in therapy would need some 10 years to reach the market, at least.
Science 29 June 2007: Vol. 316. no. 5833, pp. 1912 – 1915
HIV-1 integrates into the host chromosome and persists as a provirus flanked by long terminal repeats (LTRs). To date, treatment regimens primarily target the virus enzymes or virus-cell fusion, but not the integrated provirus. We report here the substrate-linked protein evolution of a tailored recombinase that recognizes an asymmetric sequence within an HIV-1 LTR. This evolved recombinase efficiently excised integrated HIV proviral DNA from the genome of infected cells. Although a long way from use in the clinic, we speculate that this type of technology might be adapted in future antiretroviral therapies, among other possible uses.
1 Max-Planck-Institute for Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, D-01307 Dresden, Germany.
2 Heinrich-Pette-Institute for Experimental Virology and Immunology, Martinistrasse 52, D-20251 Hamburg, Germany.
Archaeologists hailed one of the most important finds in Egyptian history on Wednesday after a broken tooth identified the 3,500-year-old mummy of Queen Hatshepsut, the most powerful female pharaoh. Billed as the most significant find since the discovery of King Tutankhamun’s tomb in 1922, Egyptian antiquities chief Zahi Hawass made the announcement to a packed press conference in Cairo.
He said one of two mummies found in a tomb in the Valley of the Kings in Luxor about a century ago had been identified as Hatshepsut, the greatest woman monarch of the ancient world.
“The discovery of the Hatshepsut mummy is one of the most important finds in the history of Egypt,” the antiquities chief said.
“I’m sure that this mummy will help us to shed light on this mystery and on the mysterious nature of her death.”
Hatshepsut ruled for 21 years from 1479 to 1458 BC, declaring herself pharaoh after the death of her husband and half-brother Tuthmosis II.
The fabled queen, known for sporting a false beard and dressing like a man, was identified thanks to a broken tooth following examinations of four mummies from the New Kingdom using the latest forensic technology.
Hawass said the mummy identified as Hatshepsut was of a “fat woman in her 50s who probably died of cancer.”
In 1903, archaeologist Howard Carter — who later made history with his discovery of Tutankhamun– found two sarcophogi in tomb 60 in the Theban necropolis, the Valley of the Kings in Luxor.
One apparently contained the mummy of Hatshepsut’s wet nurse, Sitre-In, and the other of an unknown female.
Later in 1920, he found the magnificent funerary temple of Deir el-Bahari which Hatshepsut had built for herself at Luxor.
Mysteriously, two sarcophogi found in the temple were empty.
That is where the search for Hatshepsut had ended until the US-based Discovery Channel asked Hawass to take another look.
The mummies from tomb 60 were brought to Cairo for the first time and Hawass used CT scans to produce detailed 3D images which linked physical traits of the unidentified mummy to those of Hatshepsut’s relatives.
But the definitive proof, according to Hawass, was found in an ancient box bearing the female pharaoh’s royal seal which was discovered in 1881 at her famous Deir el-Bahari temple, scene of a bloody massacre of tourists in 1997.
Inside the box were organs from a mummy and a tooth. Examined for its possible connection to a missing molar in the unidentified mummy from tomb 60, analysts found a match.
He said the find could help to explain the mystery of Hatshepsut’s disappearance from the ancient record after her death and the empty sarcophogi in her burial temple.
“Her reign during the 18th dynasty of ancient Egypt was a prosperous one, yet mysteriously she was erased from Egyptian history,” he said.
American Egyptologist Elizabeth Thomas first suggested years ago that the second mummy in tomb 60 belonged to Hatshepsut, because her hand was resting on her chest in a position reserved for monarchs.
Discovery said a team of archaeologists would now carry out DNA testing on the mummy to confirm her identity.
Hatshepsut, the only legitimate daughter of Pharaoh Tuthmosis I who ruled from 1504-1484 BC, reigned before female pharaohs Nefertiti and Cleopatra and is thought to have exercised greater power.
After the early death of her husband Tuthmosis II, she reigned as regent for his son by a concubine, Tuthmosis III, who was too young to rule.
Hatshepsut declared herself pharaoh, donning royal headdress and a false beard, and claimed divinity through the intervention of the god Amun-Ra.
Her rule is seen as a time of stability and prosperity for Egypt, associated more with commerce than conquest, especially the opening of trade routes to Nubia and Somalia in the south. Her most famous landmark is Deir el-Bahari.
Records of her reign suddenly end after her death. Her jealous successor Tuthmosis III — long kept in the shadows — demolished her monuments and her mummy was thought to have been lost forever.
“This was a pure settling of dynastic scores and not a misogynist political reaction against the promotion of a woman to the supreme position,” said French expert Jean Yoyotte.
© 2007 AFP
die meisten grausamkeiten werden aus schwäche begangen.
A unique study by researchers at the University of York and Hull York Medical School has confirmed a link between depression and low levels of folate, a vitamin which comes from vegetables.
In research published in the July edition of the Journal of Epidemiology and Community Health, the York team led by Dr Simon Gilbody, concluded that there was a link between depression and low folate levels, following a review of 11 previous studies involving 15,315 participants.
Last month, the Food Standards Agency recommended to UK Health Ministers the introduction of mandatory fortification of either bread or flour with folic acid to prevent neural tube defects, which can result in miscarriage, neonatal death or lifelong disability. The York study suggests that the measure may also help in the fight against depression.
Dr Gilbody said: “Our study is unique in that for the first time all the relevant evidence in this controversial area has been brought together. Although the research does not prove that low folate causes depression, we can now be sure that the two are linked. Interestingly, there is also some trial evidence that suggests folic acid supplements can benefit people with depression. We recommend that large trials should be carried out to further test this suggestion.”
Recent research from the same team published in the American Journal of Epidemiology has also proved that people with depression commonly have a gene that means that they process folate less efficiently. Folate is linked to the production of some of the ‘feel good’ chemicals in the brain, such as serotonin. The identification of this gene provides a plausible explanation as to why folic acid supplements may help people with depression.
Depression may soon become the second leading cause of disability worldwide. It affects between 5% and 10% of individuals and is the third most common reason for consultation in primary care.
Gilbody S, Lightfoot T and Sheldon T.
‘Is low folate a risk factor for depression? A meta-analysis and exploration of heterogeneity’.
Journal of Epidemiology and Community Health 2007; 61: 631-637.
Gilbody S, Lewis S and Lightfoot T.
‘MTHFR polymorphisms and psychiatric disorders: a HuGE review’.
American Journal of Epidemiology 2007; 165: 1-13.
On Tuesday, June 25 2007, I read that charges of disturbing the peace have been filed in Nepal against a self-styled holy man who caused a panic by predicting a massive earthquake.
I read, that Bishweshwor Chaudhari had his followers distribute thousands of pamphlets warning that 300,000 people would die in a quake in South Asia on June 22, The Times of London reported Monday.
His prophesy caused such alarm that the Nepalese government and council of astrologers had to issue formal denials.
When the day came and went without a tremor, angry residents stormed his house and demanded that Chaudhari be punished.
A former builder, Chaudhari moved to Nepal three years ago and set himself up as a holy man, The Times reported.
The predominantly Hindu nation, one of the poorest in the world, has many holy men who earn money by making prophesies, delivering blessings and selling questionable remedies, the newspaper said.
What I don’t read is, that anyone did file any charge of disturbing peace against the self-styled holy men of the Bush administration. They too do earn money with shady political remedies, obscurantist prophesies and dubiuos blessings. But while in Nepal nothing really happened about the missed earthquake, the prophesied weapons of mass distruction in Iraq did not only not surface, but Bush threw the whole area in a still contiuing warfare, and keeps waging war against the whole Muslim world for a prophesied clash of the cultures that so far did not happen to happen either.
Students With Symptoms Of Mental Illness Often Don’t Seek HelpStudies show that the incidence of mental illness on college campuses is rising, and a new survey of 2,785 college students indicates that more than half of students with significant symptoms of anxiety or depression do not seek help.
This is despite the fact that resources are available at no cost on campus, said Daniel Eisenberg, assistant professor at the University of Michigan School of Public Health. Eisenberg and doctoral students Sarah Gollust and Ezra Golberstein conducted the Web-based survey in an attempt to quantify mental health service use and factors associated with whether or not students seek help. A study looking at the same issues at 12-15 universities nationwide will begin this fall, Eisenberg said.At U-M where the study occurred, students have access to free mental health and counseling services. Yet, among those with significant symptoms of depressive or anxiety disorders, anywhere from 37 to 84 percent of students didn’t seek treatment, depending on the disorder. However, 72 percent of students with positive screens for major depression did acknowledge they needed help for their mental health. Overall, about 10 percent of students surveyed said they received therapy, and the same percentage said they took some type of psychotropic drug.
“We can’t assume that reducing financial barriers is enough,” Eisenberg said. The study found that one of the biggest predictors of whether a student sought help was socioeconomic background—students who reported growing up in poor families were almost twice as likely not to seek help. Poor students were also much more prone to symptoms of depression and anxiety disorders.
Other factors associated with not seeking treatment included lack of perceived need, being unaware of services or insurance coverage, skepticism about effectiveness, or being Asian or Pacific Islander. Women were more likely to realize they need treatment and seek it, he said.
It’s important to understand what motivates students to seek help or not for several reasons, Eisenberg said. Most mental disorders first occur before age 24, and those problems often have long-term implications into adulthood. Studying a university setting lends insight into what other factors besides affordability keep people from seeking help.
U-M is a national leader in efforts to reach students and educate them about resources available, Eisenberg said. The University recently developed a mental health assessment instrument that will be used by a national network of counseling centers, conducted a stigma reduction campaign called “Real Men, Real Depression,” developed a mental health resources web site, and hosts a Depression on College Campuses conference annually.
Eisenberg stressed that even though the incidence of mental disorders on college campuses is rising, studying the conditions surrounding the phenomenon presents an opportunity.
“Often college student mental health is framed as a problem on the rise,” Eisenberg said. “One can also think of it as a unique opportunity because college campuses offer several ways to reach students and affect their lives positively.”
Once more this reading of results is a bit unilateral. Certainly there does exist a deplorably high number of students who could benefit from psychotherapeutical assistance, but do not seek for it. But at figures ragning from 37% to 84% –depending upon disorder– at least three more questions should be allowed:
1) How reliable are the screening instruments, that are the methodical cornerstone within the proof for those students indeed being mentally ill? Among the factors that kept students from seeking help was mentioned a lack of perceived need. In my professional experience I have not really encountered anxious or depressed individuals unaware of this condition.
2) To which degree these figures do reflect social conditions on the campus, which is obviously not just an “environment with universal access to free short-term psychotherapy and basic health services”?
3) How are depression and anxiety among campus students correlating with levels of depression and anxiety in the whole generation, or, even the whole society? Are the studied campuses representative for an underlying trend within social discourse and self-perception?
Help-Seeking and Access to Mental Health Care in a University Student Population.
Medical Care. 45(7):594-601, July 2007.
Eisenberg, Daniel PhD; Golberstein, Ezra BA; Gollust, Sarah E. BA
Background: University students represent an important population in which to study access to mental health care. Understanding their unmet needs will enhance efforts to prevent and treat mental disorders during a pivotal period in life.
Objective: To quantify mental health service use and estimate how various factors are associated with help-seeking and access in a university student population.
Design: A Web-based survey was administered to a random sample of 2785 students attending a large, public university with a demographic profile similar to the national student population. Nonresponse bias was accounted for using administrative data and a nonrespondent survey.
Measures: Mental health was measured using the Patient Health Questionnaire screens for depressive and anxiety disorders. Mental health service utilization was measured as having received psychotropic medication or psychotherapy in the past year.
Results: Of students with positive screens for depression or anxiety, the proportion who did not receive any services ranged from 37% to 84%, depending on the disorder. Predictors of not receiving services included a lack of perceived need, being unaware of services or insurance coverage, skepticism about treatment effectiveness, low socioeconomic background, and being Asian or Pacific Islander.
Conclusions: Even in an environment with universal access to free short-term psychotherapy and basic health services, most students with apparent mental disorders did not receive treatment. Initiatives to improve access to mental health care for students have the potential to produce substantial benefits in terms of mental health and related outcomes.
(C) 2007 Lippincott Williams & Wilkins, Inc.
BALTIMORE, June 25 (UPI) — A $500 prize is being offered for the winning name submitted for the prototype of what may be the next generation of personal computers.University of Maryland researchers said the new technology — capable of computing speeds 100 times faster than current desktops — is based on parallel processing on a single chip.
The prototype was developed by Professor Uzi Vishkin and colleagues at the university’s Clark School of Engineering.
“The single-chip supercomputer prototype … uses rich algorithmic theory to address the practical problem of building an easy-to-program multi-core computer,” said Charles Leiserson, a professor of computer science and engineering at the Massachusetts Institute of Technology. “Vishkin’s chip unites the theory of yesterday with the reality of today.”
To increase awareness of his new technology, Vishkin is inviting the public to propose names for it. The name should reflect the features and bold aspirations of the new machine and its parallel computing capabilities, Vishkin said.
The winner will receive a $500 cash prize and will be credited with the naming of the innovative technology.
Names can be submitted at http://www.eng.umd.edu. The deadline for submissions is Sept. 15.