Research

Rise and shine

Medication introduced to help people stay awake, has wider implications than was first thought. Modafinil appears to improve certain mental abilities, or cognitive functioning, without the side effects commonly experienced with other mental stimulants. Danielle Turner, from the Department of Psychiatry, took a group of 60 healthy young males though a series of cognitive tests, after they had each received either a dummy tablet (placebo) or modafinil.

"In the study, the volunteers given modafinil performed significantly better at neuropsychological tests involving short-term memory and showed less impulsive responding and an increased tendency to reflect on the tasks they were given," she said. "The research suggests that it may at last be possible to help patients with neuropsychiatric disorders, such as Attention Deficit Hyperactivity Disorder (ADHD), who suffer from selective impairments in memory, problem-solving and planning."

Drugs such as amphetamine and methylphenidate have been used previously to help improve some aspects of people's performance, but often have the disadvantages of causing impairments in other and serious side effects such as addiction. Modafinil, in contrast, has been shown to have few side effects and no evidence of addiction.

"Our future study will test whether young adults suffering from ADHD show similar improvements to our healthy volunteers. Using brain-imaging equipment we will also be able to take dynamic scans of our patients' brains while they are performing the tests. Visualising modafinil acting in the brain could help us find out exactly which brain cells (or neurones) and neurochemicals are involved in our memory and problem solving processes."

New solution to a smelly problem

A team of researchers at the Department of Chemical Engineering has commissioned new equipment for producing renewable energy from waste materials.

The team has developed a fluidised bed reactor for producing a clean-burning, hydrogen-rich fuel gas from municipal sewage sludge. "Current methods to treat the vast quantities of sludge produced in Europe include spreading it on agricultural land, burning it or burying it in a landfill. There are quite a few negative connotations associated with these alternatives. Our work aims to give an environmentally acceptable one," says Dr Andrew Harris, project researcher and Research Fellow at Darwin College.

Dr Harris, together with his colleagues Dr John Dennis, Professors Alan Hayhurst and John Davidson and PhD student Stuart Scott, aim to produce a valuable hydrogen-rich gas from the waste material and at the same time minimise harmful emissions and by-products.

"There is a lot of talk at the moment about the new hydrogen economy, but nobody goes into much detail about where all this hydrogen is going to come from. Our technology has the potential to produce large quantities of hydrogen from waste materials, relatively cheaply," says Dr Dennis.

Natural radioactivity affects human DNA

New research by Cambridge scientists suggests that even relatively low doses of radiation can cause mutations in human DNA.

The study found DNA mutations in people living in Kerala, a coastal region of southern India where the natural level of radiation is 10 times higher than the global average. The researchers analysed the DNA of individuals who have been exposed to natural radiation throughout their lives; residents from nearby low-radiation islands served as a control population. The researchers looked at the DNA from mitochondria (mtDNA), which is inherited only from the mother, and can thus be used to determine whether a mutation is transferred across generations.

The scientists identified 22 mutations in the mtDNA sequences of families living in the high-radiation area - the control population living in a low-radiation area nearby had only one mutation. "Our findings indicate that radiation indirectly increases the cell's normal (evolutionary) mutation mechanism," said Dr Lucy Forster, a molecular geneticist at the University's McDonald Institute for Archaeological Research and lead author on the team's research paper.

The findings do not establish direct link between the 22 mutations and disease. "We intentionally analysed a non-coding region of the DNA where mutations have no effect on health or on any other visible features," said Peter Forster, another member of the research team. "But perhaps it is happening to other genes and maybe it is happening to genes that have been linked to cancer."

Currently the maximum radiation exposure allowed for workers in research or in nuclear facilities is 50 times higher than normal, five times that found in Kerala. "It might be worth considering whether to lower the allowed limits for radiation workers of reproductive age," said Dr Forster,.

Education research focuses on national priorities

What do teachers and the public really think about teaching as a profession and what are the prospects for strategies to enhance teachers' status? These are two key questions a research team from the Faculty of Education will be addressing for the DfES over the next 4 years.

The £800k grant is one of the largest ever awarded to the Faculty. Led by Dr Linda Hargreaves, the team will explore a range of possible influences using a mixture of approaches, including a survey of 5,000 teachers; in-depth interviews; opinion polls and analyses of media images. The Teacher Status research is the latest of four major studies the Faculty has won from the DfES. Earlier in the year John Gray and John MacBeath secured funds to study improvement processes in some of the country's toughest and most disadvantaged schools.

Molly Warrington and Mike Younger have been working on another national priority. Their innovative research and intervention project is testing promising ideas for raising boys' achievement in some 50 primary, secondary and special schools. Meanwhile, Maurice Galton, Jean Rudduck and John Gray have reached the final stages of their project. Working with schools nation-wide, they have been exploring how pupil progress and motivation can be enhanced as pupils move from one year to the next and from primary to secondary school. They reported their main findings to policy-makers at the end of last month.

The fight against cancer

Cambridge scientists believe they have uncovered one of the cancer-causing secrets of the breast cancer gene BRCA2. Faulty BRCA2 not only causes breast cancer in up to 60 per cent of women who inherit it, but also raises the risk of ovarian cancer and prostate cancer in men - yet scientists have never understood its precise mechanism of action. But writing in the journal Nature last month, Luca Pellegrini, Tom Blundell, Ashok Venkitaraman and colleagues at the University of Cambridge revealed how damaged BRCA2 loses control of a key molecule that helps hold our genetic information together. BRCA2 normally controls a molecule called Rad51, which is involved in repairing DNA and keeps the genes in a cell intact. The researchers studied precisely how the BRCA2 protein molecule, produced from the gene, interacts with Rad51 and how the process goes wrong when BRCA2 is faulty.

They discovered that BRCA2 has eight 'Velcro strips', each of which attaches to Rad51 using a multitude of tiny molecular hooks. By sticking to the Rad51 molecule, BRCA2 may direct it accurately to sites of DNA damage and control its ability to carry out repair. Several cancer-causing versions of BRCA2 are damaged within these 'Velcro strips', hampering the ability of BRCA2 to control Rad51 and so causing cells to develop potentially cancerous mutations.

Professor Ashok Venkitaraman, of the Hutchison/MRC Research Centre in Cambridge, said: "When the BRCA2 gene is faulty, a cell's genetic information becomes increasingly unstable, making it more likely that cancer will develop. Understanding the nuts and bolts of BRCA2's function should in the future allow us to develop new types of anti-cancer drug - although progress in this direction will take more time and continued effort."