Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Biotech / Medical : Biotech Valuation -- Ignore unavailable to you. Want to Upgrade?

To: Icebrg who wrote (9245)	10/1/2003 12:39:29 PM
From: Biomaven	Read Replies (1) \| Respond to of 52153

Erik, Neither drug is going to work on all tumor cells in all patients. If you assume Tarceva/Iressa have some efficacy as monotherapy then you have to come up with some explanation of why they don't help when added to chemo. There are a number of possible explanations (but I'm talking here without much in the way of specific knowledge): 1. One unlikely explanation is that they are "dominated" by the chemo drugs - in other words they only help patients who would have been helped by the chemo anyhow. This seems unlikely because of the different modes of action and because of the fact that some patients who didn't respond to chemo still respond to Iressa. 2. A second explanation is that the drugs interfere with each other in some way. It's plausible that the EGFR drugs interfere with the efficacy of chemo, and there might be a subtle timing interaction - the combo might work much better if you alternate the drugs rather than give them at the same time. (Thus if a tumor cell escapes from the G1 phase block after a few days it would run into the chemo - as it is, by the time it escapes, the chemo might no longer be on board). It's also possible that the chemo hurts the efficacy of the EGFR drugs by breaking some existing checkpoint mechanism. Peter P.S. A nice animated diagram of the cell cycle can be found at: cellsalive.com

To: Icebrg who wrote (9245)	10/6/2003 5:49:02 AM
From: Icebrg	Read Replies (2) \| Respond to of 52153

The 2003 Nobel Prize in Physiology or Medicine 6 October 2003 The Nobel Assembly at Karolinska Institutet has today decided to award The Nobel Prize in Physiology or Medicine for 2003 jointly to Paul C Lauterbur and Peter Mansfield for their discoveries concerning "magnetic resonance imaging" Summary Imaging of human internal organs with exact and non-invasive methods is very important for medical diagnosis, treatment and follow-up. This year's Nobel Laureates in Physiology or Medicine have made seminal discoveries concerning the use of magnetic resonance to visualize different structures. These discoveries have led to the development of modern magnetic resonance imaging, MRI, which represents a breakthrough in medical diagnostics and research. Atomic nuclei in a strong magnetic field rotate with a frequency that is dependent on the strength of the magnetic field. Their energy can be increased if they absorb radio waves with the same frequency (resonance). When the atomic nuclei return to their previous energy level, radio waves are emitted. These discoveries were awarded the Nobel Prize in Physics in 1952. During the following decades, magnetic resonance was used mainly for studies of the chemical structure of substances. In the beginning of the 1970s, this year’s Nobel Laureates made pioneering contributions, which later led to the applications of magnetic resonance in medical imaging. Paul Lauterbur (born 1929), Urbana, Illinois, USA, discovered the possibility to create a two-dimensional picture by introducing gradients in the magnetic field. By analysis of the characteristics of the emitted radio waves, he could determine their origin. This made it possible to build up two-dimensional pictures of structures that could not be visualized with other methods. Peter Mansfield (born 1933), Nottingham, England, further developed the utilization of gradients in the magnetic field. He showed how the signals could be mathematically analysed, which made it possible to develop a useful imaging technique. Mansfield also showed how extremely fast imaging could be achievable. This became technically possible within medicine a decade later. Magnetic resonance imaging, MRI, is now a routine method within medical diagnostics. Worldwide, more than 60 million investigations with MRI are performed each year, and the method is still in rapid development. MRI is often superior to other imaging techniques and has significantly improved diagnostics in many diseases. MRI has replaced several invasive modes of examination and thereby reduced the risk and discomfort for many patients.