Patients Denied Admission To Intensive Care Because Of Doctors' Pessimism, Study Says
ScienceDaily (Nov. 3, 2007) — Doctors are overly pessimistic about the chances of survival for patients with COPD related attacks and, as a result, some patients may be denied admission to hospital for vital help, according to a study published on the British Medical Journal website.
COPD (chronic obstructive pulmonary disease) causes around 30,000 deaths a year in the UK and many patients who have COPD attacks can benefit from assisted ventilation, but they have to be admitted to an intensive care unit (ICU) to be intubated.
Researchers studied results from 92 intensive care and three respiratory high dependency units in the UK that dealt with 832 patients aged 45 years and over who had breathlessness, respiratory failure or change in mental status due to a COPD attack, asthma or both.
Information gathered over an 18-month period from a database covering 74% of UK ICUs said there was no significant difference in outcomes when comparing units that took part in the study and those that did not.
Overall, 517 (62%) patients survived to 180 days after the incident, but clinicians prognoses were pessimistic, predicting a survival rate of just 49%.
For the fifth of patients with the poorest prognosis according to the clinician, the predicted survival rate was 10% and the actual rate was 40%
The survival rates were 80% at discharge from ICU or high dependency units, 70% at discharge from hospital and 62% at 180 days after ICU admission.
The authors say: "Clinicians are generally pessimistic about the survival of patients with exacerbations of COPD and have particular problems in identifying those with poor prognosis. Patients might therefore be inappropriately excluded from intensive care and the chance of intubation on the basis of a false prediction of futility."
In an accompanying editorial, US researchers point to a scarcity of intensive care resources as a possible explanation for these results.
They say that making decisions about admission to intensive care is complex, especially in the UK and southern Europe, where intensive care beds are often lacking. And they call for further studies to determine whether prognostic pessimism requires intervention aimed at doctors or at underlying healthcare systems that have inadequate provision of critical care services.
‘Look, I don’t think you’re going to make it. Could I have your lunch?”
Headline of the day (from the Obscure Store)
Fiance suffers breakdown after beau is caught with corpse
We’ve got five bucks that says the radio signal consisted of Ted Nugent rockin “Cat Scratch Fever.” No wonder the liver started to straighten out.
Radio Waves Fire Up Nanotubes Embedded In Tumors, Destroying Liver Cancer
ScienceDaily (Nov. 3, 2007) — Cancer cells treated with carbon nanotubes can be destroyed by non-invasive radio waves that heat up the nanotubes while sparing untreated tissue, a research team led by scientists at The University of Texas M. D. Anderson Cancer Center and Rice University has shown in preclinical experiments.
Researchers show that the technique completely destroyed liver cancer tumors in rabbits. There were no side effects noted. However, some healthy liver tissue within 2-5 millimeters of the tumors sustained heat damage due to nanotube leakage from the tumor.
"These are promising, even exciting, preclinical results in this liver cancer model," says senior author Steven Curley, M.D., professor in M. D. Anderson's Department of Surgical Oncology. "Our next step is to look at ways to more precisely target the nanotubes so they attach to, and are taken up by, cancer cells while avoiding normal tissue."
Targeting the nanotubes solely to cancer cells is the major challenge in advancing the therapy, Curley says. Research is under way to bind the nanotubes to antibodies, peptides or other agents that in turn target molecules expressed on cancer cells. To complicate matters, most such molecules also are expressed in normal tissue.
Curley estimates that a clinical trial is at least three to four years away.
Curley conducted the research at M. D. Anderson in collaboration with nanotechnology experts at Rice University and with Erie, Pennsylvania, entrepreneur John Kanzius of ThermMed LLC, who invented the experimental radiofrequency generator used in the experiments. Kanzius is a cancer survivor and former radio station owner whose insights into the potential of targeted radio waves inspired this line of research.
At Rice, the work was begun by Nobel laureate Richard Smalley, several months before his untimely death from cancer in October 2005. Smalley was the founder of Rice's Carbon Nanotechnology Laboratory and one of the world's foremost experts on carbon nanotubes. He shared the Nobel Prize for the 1985 discovery of fullerenes, the family of carbon molecules that includes nanotubes. His research in 2005 was concentrated largely on the radiofrequency cancer research project.
Rice materials scientist professor Boris Yakobson, Ph.D., a co-author on the paper, recalled meeting with Smalley in his hospital room at M. D. Anderson five days before his death.
"He looked very ill, breathing heavily through the oxygen mask, but all he wanted to do was talk about the physics of this very phenomenon," Yakobson said. "Oblivious of his ebbing health, Rick was focused in the future. He had told Congress in 1999 that nanotechnology would help revolutionize cancer treatment, and he was a scientist wanting to know whether this technology might be one of the things that would make that possible."
In the liver cancer experiment, a solution of single-walled carbon nanotubes was injected directly into the tumors. Four treated rabbits were then exposed to two minutes of radiofrequency treatment, resulting in thermal destruction of their tumors.
Carbon nanotubes are hollow cylinders of pure carbon that measure about a billionth of a meter, or one nanometer, across.
Control group tumors that were treated only by radiofrequency exposure or only by nanotubes were undamaged.
In lab experiments, two lines of liver cancer cells and one pancreatic cancer cell line were destroyed after being incubated with nanotubes and exposed to the radiofrequency field.
"I'm humbled by the results of this research," says Kanzius. "I realize it's early in the race, but Dr. Curley and his team have moved on this carefully with utmost speed. I look forward to continuing to work with them and hopefully to watching the first person be treated with this procedure. The race isn't over but it needs to be taken to the finish line."
Radiofrequency energy fields penetrate deeply into tissue, so it would be possible to deliver heat anywhere in the body if targeted nanotubes or other nanoparticles can be delivered to cancerous cells, Curley says. Without such a target, radio waves will pass harmlessly through the body.
An invasive technique known as radio frequency ablation is used to treat some malignant tumors, the authors note. It requires insertion of needle electrodes directly into the tumors. ncomplete tumor destruction occurs in 5 to 40 percent of cases, normal tissue is damaged and complications arise in 10 percent of patients who suffer such damage. Radiofrequency ablation is limited to liver, kidney, breast, lung and bone cancers.
This research appeared online ahead of December publication in the journal Cancer.
It must be where humans get the fashion gene
Gliding mammal linked to humans
By Helen Briggs
Science reporter, BBC News
A gliding mammal that lives in the forests of south-east Asia is our closest relative after apes, monkeys and lemurs, a DNA study shows.
Colugos are the "sisters" of primates, sharing a common ancestor some 80 million years ago when dinosaurs had their heyday, say US scientists.
Until now, many experts thought tree shrews were closer to primates.
Writing in Science, the team calls for urgent action to decipher the full genome sequence of colugos.
Colugos are known colloquially as flying lemurs; despite this they do not fly and they are not true lemurs.
Bat-like in appearance, and the size of a large squirrel, they use a special fold of skin to glide from tree to tree in tropical rainforests.
This study resolves a long-standing question on who the closest relative of primates was
Dr William Murphy
They looked at genetic "mistakes", or mutations, in the DNA "letters" of the genome sequence of primates, colugos and tree shrews - the animals that are most alike.
After comparing the three groups to about 30 other mammal species, they found that primates and colugos shared seven genetic changes that were very rare in other mammals.
In the second study, researchers used computer programs to search for similarities and differences in 13,000 DNA building blocks from five close animal groups - primates, the colugo family, tree-shrews, rodents and the order that includes hares and rabbits.
The research revealed that colugos and primates are more closely related than tree shrews and primates, solving a decade-long debate.
Image courtesy of Norman Lim, National University of Singapore
Colugos were once thought close to the ancestors of bats
"This study resolves a long-standing question to primatologists and mammalologists on who the closest relative of primates was," co-author William J Murphy of Texas A&M University told BBC News.
"This will help us better interpret early primate evolution and those changes at the DNA level and in skeletal appearance that led to modern primates and ultimately to the human lineage itself."
The research team wants this new knowledge to be used to ensure that colugos have their full genome sequenced rather than only a less complete "draft" sequence as planned.
It also has a rudimentary language— a single utterance that sounds like it’s saying “fabulous.”
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