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This week The Alchemist learns of a major new grant awarded to Florida scientists to help fight cancer. In physical chemistry, friction at the atomic level is revealed with modified atomic force microscopy and there is depressing news in the pharma field as UK researchers demonstrate that modern antidepressants may work no more effectively than a placebo except in extreme cases. A seventy-year old search for a mould chemical involved in the spread of Phytophthora in crop plants and oak trees could soon lead to a new approach to combating these devastating pathogens. In forensics news, scientists have shown that an isotopic analysis of one's hair can reveal where you usually drink. Finally, microscopic rust-like particles found in the brain could be involved in neurodegenerative diseases and could point to a new approach to therapy.

The American Cancer Society has awarded $707,000 to Yanchang Wang, assistant professor of biomedical sciences in the Florida State University College of Medicine. He hopes to use the money to figure out how the enzyme Cdc14 can deactivate the runaway cell division process in cancer. The enzymes are part of the cellular signaling system that protects genes and chromosomes when cells divide, Wang explains. "From this proposed experiment, we expect to find a new way to regulate cell division," he says, "Cdk1 is the key driving force for cell division, so it's quite important."

Andreas Heinrich and Markus Ternes at IBM's Almaden Research Center, in San Jose, California together with Franz Giessibl at the University of Regensburg, Germany, and their colleagues have for the first time measured the force needed to move a single atom across a surface. Their results now mean that friction can be studied at the atomic level as never before. The team used a modified atomic force microscope in ultrahigh vacuum at 5 K to measure the lateral and vertical forces exerted on a cobalt atom as the AFM tip dragged it across a metal surface.

A meta study of clinical trials into the efficacy of the antidepressant drugs known as selective serotonin reuptake inhibitors (SSRIs) has revealed that they could be no better than placebo except in extremely severe forms of depression. Writing in PLoS Medicine Irving Kirsch and colleagues at the University of Hull, UK, have analyzed results for fluoxetine (Prozac), venlafaxine (Effexor), nefazodone (Serzone), and paroxetine (Seroxat / Paxil) and found them wanting. By including data from unpublished as well as published trials, the researchers set out to avoid bias that might come from non-publication of disappointing findings. Needless to say the manufacturers of these products have responded in kind with a rebuttal of the findings.

The Phytophthora pathogen ravages plants. Now, after a seventy-year hunt hormone alpha1, which gives this group of moulds their great virulence has been revealed by three teams working together in China and Japan. Phytophthora moulds are responsible for widespread economic damage, including Sudden Oak Death, a disease that has devastated US oak tree populations in California and Oregon. Fungicides have until recently kept crop plants attacked by the pathogen under control, but resistant strains are emerging. Developing inhibitors of the receptors for the hormone could lead to a new way to protect plants from this pathogen.

An isotopic analysis of one's hair can reveal where a person drank water, according to a study published in Proceedings of the National Academy of Sciences by Thure Cerling of the University of Utah and colleagues. The discovery could help forensic scientists track the past movements of criminal suspects or unidentified murder victims. "You are what you eat and drink - and that is recorded in your hair," explains geochemist Cerling, who worked with ecologist Jim Ehleringer on the study. "We have found significant variations in hydrogen and oxygen isotopes in hair and water that relate to where a person lives in the United States," Ehleringer adds, "Police are already using this to reconstruct the possible origins of unidentified murder victims." Their new approach to hair analysis may also prove useful to anthropologists, archaeologists and in medicine.

Iron is a mineral essential to life, but it can also cause damage. The role of iron deposits in the brain is thought to be involved in neurodegenerative diseases such as Parkinson's, Huntington's, and Alzheimer's. Peter Sadler of the University of Warwick in Coventry, UK and Sandeep Verma of the Indian Institute of Technology, Kanpur, India, are investigating how a malfunction of the blood transporter protein transferrin may be involved. They have now demonstrated that transferrin can clump together to form wormlike fibrils, which then release rust-like iron particles in the brain causing harm. The findings may one day provide a target for novel therapies.