Researchers at UCLA report that they have refined a method they previously developed for capturing and analysing cancer cells that break away from patients’ tumours and circulate in the blood. With the improvements to their device, which uses a Velcro-like nanoscale technology, they can now detect and isolate single cancer cells from patient blood samples for analysis.
Circulating tumour cells, or CTCs, play a crucial role in cancer metastasis, spreading from tumours to other parts of the body, where they form new tumours. When these cells are isolated from the blood early on, they can provide doctors with critical information about the type of cancer a patient has, the characteristics of the individual cancer and the potential progression of the disease. Doctors can also tell from these cells how to tailor a personalised treatment to a specific patient.
In recent years, a UCLA research team led by Hsian-Rong Tseng, an associate professor of molecular and medical pharmacology at the Crump Institute for Molecular Imaging and a member of both the California NanoSystems Institute at UCLA and UCLA’s Jonsson Comprehensive Cancer Center, has developed a ‘NanoVelcro’ chip. When blood is passed through the chip, extremely small ‘hairs’

Chemists have developed a prototype medical dressing that detects the first signs of the lethal Toxic Shock Syndrome along with other burn wound infections and could potentially save the lives of children with serious burns.

Toxic Shock Syndrome (TSS) is a serious complication of burn infections and particularly dangerous in children under four due to their immature immune systems. Left untreated, a child with a relatively small burn who develops TSS can rapidly deteriorate within a few hours. If left untreated, fifty per cent of children with the full-blown disease can die.

Scientists at the University of Bath have been working with clinicians at the South West Paediatric Burns Centre at Frenchay Hospital in Bristol to create an advanced wound dressing that can detect key microbial pathogens including the bacteria which cause TSS.

They have now developed a prototype dressing that releases dye from nano-capsules triggered by the presence of disease-causing pathogenic bacteria. The dye fluoresces under ultraviolet (UV) light, alerting healthcare professionals that the wound is infected.

The nano-capsules mimic skin cells in that they only break open when toxic bacteria are present, not responding to the harmless bacteria that normally live on healthy skin.

Dr Toby Jenkins, Reader in Biophysical Chemistry at Bath, is leading the project. He explained: ‘Around 5,000 children a year in England and Wales are hospitalised or treated in hospital with serious burns, mostly scalds caused by tea and coffee.

‘The big problem for clinicians is the fast diagnosis of infection. Current methods take between 24 and 48 hours to get an answer as to whether the wound is infected.

‘However our burns dressing gives a simple colour change under UV light if a pathogenic, disease-causing bacteria is present in the burn, meaning clinicians can be alerted quickly to a potential infection.’

Dr Amber Young, Consultant Paediatric Anaesthetist at the South West Paediatric Burns Centre at Frenchay Hospital and Paediatric Clinical Lead South West UK Burn Care Network, is the clinical consultant on the project. She said: ‘At the moment when a child with a small burn develops a high temperature we have no easy way of knowing if the child has a serious bacterial infection, or simply a cough or cold.

‘We currently have to remove the dressing to test for infection, which may result in slower healing and potentially life-long scarring, and is very distressing for the child. This new dressing will mean we will be able to detect the early signs of infection so we can diagnose and treat the child quickly.

‘It could make a real difference to the lives of many thousands of children.’

The prototype has been tested on skin samples in the lab and is currently being optimised for stability and shelf-life. The researchers expect to start safety trials on healthy human volunteers in four years.

Amid increasing fear of overexposure to radiation from CT scans, a panel of experts has recommended more research on the health effects of medical imaging and ways to reduce unnecessary CT tests, as well as industry standardisation of CT machines.
The recommendations were developed at the Radiation Dose Summit, organised by the National Institute of Biomedical Imaging and Bioengineering (NIBIB). The summit included more than 100 medical physicists, radiologists, cardiologists, engineers, industry representatives and patient advocates. The proceedings, held in Bethesda, MD in early 2011, covered currently understood risks of radiation exposure from CT scans, set priorities for future research, and called for changes to industry practices.
‘The number of CT exams in the U.S. has increased by about 10 percent each year over the past decade,’ said John Boone, UC Davis professor of radiology and lead author of the Radiology article. ‘This trend underscores the importance of developing a better understanding of the health risks of radiation exposure versus the benefits of enhanced diagnosis.’
The experts conceded that despite widespread public concern about radiation risks, the biologic effects from medical imaging tests are not entirely understood. Most direct evidence comes from the effects of instantaneous, high-dose, whole-body exposures due to industrial accidents and from survivors of the atomic bombs in Hiroshima and Nagasaki, Japan. Whether these findings can be extrapolated to people exposed to occasional and much smaller dosages applied to only parts of the body is uncertain.
‘The standards regarding ‘safe levels’ of radiation were designed for workplace safety and are very conservative,’ said Boone. ‘We don’t know whether the established thresholds are really meaningful for exposure from medical testing.’
The experts pointed out that because there is a high background incidence of cancer world-wide, the small incremental increase in cancer that may be attributable to low doses of radiation from medical imaging is extremely difficult to ascertain. They stated that national and international registries that track cancers and patient exposures to medical radiation may one day make it possible to conduct large epidemiological studies that could help make such associations.
‘In reaction to media coverage of radiation overexposure cases, some patients refuse to undergo medical imaging procedures,’ said Boone. ‘Yet for almost all patients, the risks of foregoing a needed medical procedure far outweigh any potential radiation-associated risks.’
Even accurately recording patient exposures of radiation from medical imaging is extremely difficult, according to the authors. Although it is easy to ascertain how much radiation a machine administers during an imaging study, the amount actually received by a patient depends on various factors including body size. For example, because of differences in body mass, children and small adults can receive a dose of radiation two to three times that of larger people, even when the dose administered is the same.
Other factors, such as whether the patient lies on a moving or stationary table, also affect the radiation dose received. Federally sponsored research is needed to develop methods to more accurately measure patient exposures from different types of CT scans, the authors suggested. UC Davis Comprehensive Cancer Center

Scientists from Israel and China found the test was 90% accurate at detecting and distinguishing cancers from other stomach complaints in 130 patients. The British Journal of Cancer says the test could revolutionise and speed up the way this cancer is diagnosed.

About 7,000 UK people develop stomach cancer each year and most have an advanced stage of the disease. Two-fifths of patients survive for at least a year, but only a fifth are still alive after five years, despite treatment.

Currently doctors diagnose stomach cancer by taking a biopsy of the stomach lining using a probe and a flexible camera passed via mouth and down the gullet. The new test looks for chemical profiles in exhaled breath that are unique to patients with stomach cancer.

Cancer appears to give off a signature smell of volatile organic compounds that can be detected using the right technical medical kit – and perhaps even dogs.

The science behind the test itself is not new – many researchers have been working on the possibility of breath tests for a number of cancers, including lung.

In the study, 37 of the patients had stomach cancer, 32 had stomach ulcers and 61 had other stomach complaints.

As well as accurately distinguishing between these conditions 90% of the time, the breath test could tell the difference between early and late-stage stomach cancers.

The team are now running a bigger study in more patients to validate their test.

Kate Law, director of clinical research at Cancer Research UK, said: ‘The results of this latest study are promising – although large scale trials will now be needed to confirm these findings.

‘Only one in five people are able to have surgery as part of their treatment as most stomach cancers are diagnosed at stages that are too advanced for surgery. Any test that could help diagnose stomach cancers earlier would make a difference to patients’ long-term survival.’