jueves, 9 de abril de 2009

Carbon Nanotubes Detect Lung Cancer Markers in the Breath

(PhysOrg.com) -- Using an array of nanotube devices, each coated with a different organic material, researchers at the Israel Institute of Technology have developed diagnostic system that may be able to diagnose lung cancer simply by sampling a patient’s breath. The results of this study, which was led by Hossam Haick, Ph.D., appear in the journal Nano Letters.
Dr. Haick and his collaborators first created individual devices consisting of random networks of single-walled carbon nanotubes coated with 1 of 10 different insulating nonpolymeric organic materials. The investigators used standard microprocessor fabrication techniques to create the sensors. Thanks to the different organic materials used to coat the nanotubes, each sensing device provided a unique response when exposed to wide variety of the more than 200 volatile organic chemicals present in human breath.
To calibrate the devices, the investigators captured the breath of 15 nonsmoking healthy patients and 15 individuals with stage 4 lung cancer. Next, they concentrated the organic compounds in each breath sample using a method known as solid phase microextraction and then analyzed each sample using gas chromatography-mass spectrometry (GC-MS). GC-MS is a highly accurate technique that is too expensive and time consuming to find use as a routine diagnostic assay. The researchers then ran the same samples through their sensor array; the electrical output of the test devices changed in a way that was characteristic of the exact mixture of organic compounds found in the breath samples.
From these data, the investigators were able to distinguish between two response patterns from each of the 10 array members. There was no overlap in the response patterns between the healthy and lung cancer patients in these first tests. The researchers are now testing their system on a much larger group of patients and healthy subjects.
This work is detailed in the paper “Detecting simulated patterns of lung cancer biomarkers by random network of single-walled carbon nanotubes coated with nonpolymeric organic materials.”
Provided by National Cancer Institute

2 comentarios:

Dr. House dijo...

These points to an interesting article in findrxonline where they talk about this subject it is necessary to inform the community.
It is ultimately the patient's responsibility to use narcotics responsibly.

A few years ago, narcotics were only prescribed after surgery, severe trauma, or for terminal cancer because of a concern over the possibility of addiction. Recently, they have been cautiously prescribed to treat moderate to severe non-malignant chronic pain in conjunction with other modalities such as physical therapy, cortisone and trigger point injections, muscle stretching, meditation, or aqua therapy. Unfortunately, the upsurge of narcotics as medical treatment also increased associated cases of abuse and addiction.
Derived from either opium (made from poppy plants) or similar synthetic compounds, narcotics not only block pain signals and reduce pain, but they affect other neurotransmitters, which can cause addiction. When taken for short periods, only minor side effects such as nausea, constipation, sedation and unclear thinking are noted.

lung cancer dijo...

Cancer occurs when normal cells undergo a transformation that causes them to grow and multiply without the normal controls. The cells form a mass or tumor that differs from the surrounding tissues from which it arises. Tumors are dangerous because they take oxygen, nutrients, and space from healthy cells.

Most lung tumors are malignant. This means that they invade and destroy the healthy tissues around them and can spread throughout the body.