Indigenous DNA, Brain Scans, Marburg & Stem Cells
Indigenous DNA, Brain Scans, Marburg & Stem Cell Insulin
Medical News Briefs By Marietta Gross
Indigenous people resist DNA-project Genographic research as neo-colonial attitude
The ambitious DNA profiling “Genographic project” (See.. http://www3.nationalgeographic.com/genographic) which seeks to retrace the path of human settlement on Earth has been encountering resistance among indigenous people. After a boycott-appeal by the US-American Indigenous Peoples Council on Biocolonialism http://www.ipcb.org, now some Maori in have also announced concerns over the project .
The project which seeks to find the settlement of the Blue Planet beginning from Africa by means of genetic samples of several 100,000 inhabitants was started in April by IBM and the science magazine National Geographic. The main point of criticism by native people is the argument, that the research is in effect a modern form of colonialism, explained Paul Reynolds from the Maori Research Centre at Auckland University.
“Indigenous people already have a history of their origin which was communicated over generations by their ancestors. Further scientific proofs are thus decrepit.”
Additionally the Maori see the extraction of DNA-samples as Tapu, meaning sacred or restricted.
Spencer Wells who is responsible for the five-year-project with an estimated cost of US$40 million dollars doesn’t see these worries. He wants to track the accurate migration route of the human species, who probably settled the Earth beginning from Africa 200,000 years ago. Recent research suggests a volcanic eruption in Sumatra decimated the species Homo Sapiens to only 2,000 individuals 70,000 years ago.
The ambitious project in which every citizen can volunteer – the equipment for the DNA-saliva costs inclusive mailing expenses $137 Dollar – is primarily interested in indigenous people who are living in isolation. Wells had detected the descendants of Genghis Khan in Northern Pakistan by means of genetic analyses.
Brain Scan Looks Into The Subconscious
A new imaging technique allows researchers to look through the eyes of their subjects. The pictures make even subconscious brain activity visible.
A Japanese team of researchers has developed a method to improve the results of brain scans. The technique enables the scientists to observe to activity of single groups of nerve cells – and read easy thoughts of their test persons.
Frank Tong from Vanderbilt University in Nashville, Tennessee, has developed the statistical method to analyze functional magnetic resonance imaging. The imaging technique (fMRi) makes visible which brain regions get activated at different requirements. Tong and one of his colleagues report in the actual edition of the magazine “Nature Neuroscience” that they could recognize in the fMRI-scans what test persons are viewing.
The researchers had shown pictures to the subjects, on which two different grids were put on top of each other. The brain scanner was focused on a region of the primary Area 17. That region contains groups of nerve cells which are becoming active, when lines or brinks are viewed. Each group reacts on different angles of the lines. By means of their activity the scientists can detect which one of the grids on the two layers was observed by the test person at that very moment.
John-Dylan Haynes and Geraint Rees from the University College London have aggravated the testing conditions. They showed a grid only for a short moment and then hid it with another picture. Although the subjects could not tell how the angles were aligned, but the fMRI scans showed, that the orientation in the Area 17 was exactly identified. This is reported by Haynes and Rees in the edition of “Nature Neuroscience”.
A similar result was demonstrated by Paul Whalen and colleagues from the University of Wisconsin-Madison. One brain region which is associated with the feeling of fear was even active when the test person was not conscious of having looked into fright widened eyes.
“If our approach is extended, you could tell by means of the brain activity what somebody is seeing or thinking”, Rees told the BBC. Possibly also subconscious attitudes and confirmations can be made visible. Adrian Burgess, neuro-psychologist from Imperial College London told the BBC, the method could also show suppressed memories and hidden fears.
Marburg-outbreak: First success messages are raising hope
In Angola is the number of new infections with the Marburg fever is declining. The situation is still critical however according to WHO.
“We are about to break in on the contagion chain”, explained Mike Ryan from the WHO alert department in Geneva. This is regarded as the most critical phase when fighting the epidemics. The assignment mustn’t be eased, but tightened.
In the recent outbreak of the haemorrhagic fever in Angola so far 266 people have come down with the illness, and 244 have died. Last week were only 15 new infections were registered, while before there were 25 to 35 cases per week. To keep the epidemics in check the WHO is examining 300 contact persons of the patients.
The Marburg-Virus is transmitted via body fluids. At the moment there is neither a vaccination nor a medicine against the disease available, which is similar to Ebola. An isolation of the patients and the protection against transmission are the only means of controlling the outbreak. The fever received its name after it was transmitted via infected monkeys in Marburg and other European cities in 1967.
Insulin Extracted From Brain Stem Cells
Researchers in the U.S. have extracted insulin for the first time from human stem cells in the brain. Their aim is to help patients of type-I-Diabetes, to which children and teens are also vulnerable.
After special treatment, insulin producing cells were formed from the neuronal brain tissue in the pancreas, reports the team of Seung Kim in the online-magazine “Plos Medicine”.
Normally stem cells develop into nerve tissue. Under the influence of an elaborate chemistry mixture they became an insulin producing cell cluster in the laboratory. After the scientists from Stanford University had transplanted the cells for which the polarity was reversed into mice, the new tissue started discharging insulin, dependent on a growing glucose-concentration. The amount of the produced insulin was however not enough for the treatment of Diabetes-patients.
This is the second time stem cells from the brain have been transformed into different body cells, writes Stanford University. For a long time scientists had considered that these neuronal stem cells can only develop into certain brain tissue. The recent work confirms that the potential of the stem cells from the brain is far bigger, said Kim.